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Sample records for satellite galileo galilei

  1. ``Galileo Galilei'' (GG) a small satellite to test the equivalence principle of Galileo, Newton and Einstein

    Science.gov (United States)

    Nobili, Anna M.; Comandi, Gian Luca; Doravari, Suresh; Bramanti, Donato; Kumar, Rajeev; Maccarrone, Francesco; Polacco, Erseo; Turyshev, Slava G.; Shao, Michael; Lipa, John; Dittus, Hansjoerg; Laemmerzhal, Claus; Peters, Achim; Mueller, Jurgen; Unnikrishnan, C. S.; Roxburgh, Ian W.; Brillet, Alain; Marchal, Christian; Luo, Jun; van der Ha, Jozef; Milyukov, Vadim; Iafolla, Valerio; Lucchesi, David; Tortora, Paolo; de Bernardis, Paolo; Palmonari, Federico; Focardi, Sergio; Zanello, Dino; Monaco, Salvatore; Mengali, Giovanni; Anselmo, Luciano; Iorio, Lorenzo; Knezevic, Zoran

    2009-03-01

    Galileo Galilei” (GG) is a small satellite designed to fly in low Earth orbit with the goal of testing the Equivalence Principle—which is at the basis of the General Theory of Relativity—to 1 part in 1017. If successful, it would improve current laboratory results by 4 orders of magnitude. A confirmation would strongly constrain theories; proof of violation is believed to lead to a scientific revolution. The experiment design allows it to be carried out at ambient temperature inside a small 1-axis stabilized satellite (250 kg total mass). GG is under investigation at Phase A-2 level by ASI (Agenzia Spaziale Italiana) at Thales Alenia Space in Torino, while a laboratory prototype (known as GGG) is operational at INFN laboratories in Pisa, supported by INFN (Istituto Nazionale di fisica Nucleare) and ASI. A final study report will be published in 2009.

  2. The GALILEO GALILEI small-satellite mission with FEEP thrusters (G G)

    Energy Technology Data Exchange (ETDEWEB)

    Nobili, A. M.; Bramanti, D.; Catastini, G. [Pisa, Univ. (Italy). Dipt. di Matematica. Gruppo di Meccanica Spaziale

    1997-09-01

    The Equivalence Principle, formulated by Einstein generalizing Galileo`s and Newton`s work, is a fundamental principle of modern physics. As such it should be tested as accurately as possible. Its most direct consequence, namely the Universality of Free Fall, can be tested in space, in a low Earth orbit, the crucial advantage being that the driving signal is about three orders of magnitude stronger than on Earth. GALILEO GALILEI (G G) is a small space mission designed for such a high-accuracy test. At the time of print, G G has been selected by ASI (Agenzia Spaziale Italiana) as a candidate for the next small Italian mission. Ground tests of the proposed apparatus now indicate that an accuracy of 1 part in 10{sup 17} is within the reach of this small mission.

  3. The GALILEO GALILEI small-satellite mission with FEEP thrusters (GG).

    Science.gov (United States)

    Nobili, A. M.; Bramanti, D.; Catastini, G.

    1997-10-01

    The Equivalence Principle, formulated by Einstein generalizing Galileo's and Newton's work, is a fundamental principle of modern physics. As such it should be tested as accurately as possible. Its most direct consequence, namely the universality of free fall, can be tested in space in a low Earth orbit, the crucial advantage being that the driving signal is about three orders of magnitude stronger than on Earth. GALILEO GALILEI (GG) is a small space mission designed for such a high-accuracy test. GG has been selected by ASI (Agenzia Spaziale Italiana) as a candidate for the next small Italian mission. Ground tests of the proposed apparatus now indicate that an accuracy of 1 part in 1017 is within the reach of this small mission.

  4. Experimental Validation of a High Accuracy Test of the Equivalence Principle with the Small Satellite "GALILEO GALILEI"

    Science.gov (United States)

    Nobili, Anna M.; Comandi, Gian Luca; Doravari, Suresh; Maccarrone, Francesco; Bramanti, Donato; Polacco, Erseo

    The small satellite "Galileo Galilei" (GG) has been designed to test the equivalence principle (EP) to 10-17 with a total mass at launch of 250 kg. The key instrument is a differential accelerometer made up of weakly coupled coaxial, concentric test cylinders rapidly spinning around the symmetry axis and sensitive in the plane perpendicular to it, lying at a small inclination from the orbit plane. The whole spacecraft spins around the same symmetry axis so as to be passively stabilized. The test masses are large (10 kg each, to reduce thermal noise), their coupling is very weak (for high sensitivity to differential effects), and rotation is fast (for high frequency modulation of the signal). A 1 g version of the accelerometer ("Galileo Galilei on the Ground" — GGG) has been built to the full scale — except for coupling, which cannot be as weak as in the absence of weight, and a motor to maintain rotation (not needed in space due to angular momentum conservation). GGG has proved: (i) high Q; (ii) auto-centering and long term stability; (iii) a sensitivity to EP testing which is close to the target sensitivity of the GG experiment provided that the physical properties of the experiment in space are going to be fully exploited.

  5. Galileo Galilei's vision of the senses.

    Science.gov (United States)

    Piccolino, Marco; Wade, Nicholas J

    2008-11-01

    Neuroscientists have become increasingly aware of the complexities and subtleties of sensory processing. This applies particularly to the complex elaborations of nerve signals that occur in the sensory circuits, sometimes at the very initial stages of sensory pathways. Sensory processing is now known to be very different from a simple neural copy of the physical signal present in the external world, and this accounts for the intricacy of neural organization that puzzled great investigators of neuroanatomy such as Santiago Ramón Y Cajal a century ago. It will surprise present-day sensory neuroscientists, applying their many modern methods, that the conceptual basis of the contemporary approach to sensory function had been recognized four centuries ago by Galileo Galilei.

  6. [Keratoacanthoma on the left cheek of Galileo Galilei].

    Science.gov (United States)

    Roth, W

    1986-09-01

    In an oil painting from the School of Sustermans, which can be seen in the Palazzo Pitti in Florence, we diagnosed the alterations typical of a keratoacanthoma in the left cheek-bone area of the portrayed Galileo Galilei.

  7. Reconstruction of Galileo Galilei's Experiment: The Inclined Plane

    Science.gov (United States)

    Straulino, S.

    2008-01-01

    In the "Third Day" of the "Discourses and Mathematical Demonstrations Concerning Two New Sciences" Galileo Galilei describes the famous experiment of the inclined plane and uses it to bring an experimental confirmation to the laws of uniformly accelerated motion. We describe a reconstruction of the experiment and how the results can be used for…

  8. Galileo Galilei (GG): the space mission and the prototype

    Science.gov (United States)

    Nobili, A.

    "GALILEO GALILEI (GG)" is a proposal to fly a small satellite in low Earth orbit aiming to test the Equivalence Principle of Galileo, Newton and Einstein to 1 part in 1017 at room temperature. Ground tests carried out with artificial test bodies on rotating torsion balances, and tests with celestial bodies based on Lunar Laser Ranging data, have found no violation to about 1 part in 1013 . Competing space pro jects are SCOPE (also at room temperature) aiming to 1 part in 1015 , and STEP (at very low temperature) aiming to 1 part in 1018 . GG is characterized by fast rotation and by the possibility to perform a full scale test on the ground. This talk will present the main features of the GG design, as compared to STEP and SCOPE, and report the experimental results obtained with the first and the second generation laboratory prototypes (natural frequencies, quality factor, stability, sensitivity). Interested scientists are welcome to visit the GG webpage at http://eotvos.dm.unipi.it/nobili.

  9. `Galileo Galilei' (GG) small-satellite project: an alternative to the torsion balance for testing the equivalence principle on Earth and in space

    Science.gov (United States)

    Nobili, A. M.; Bramanti, D.; Polacco, E.; Roxburgh, I. W.; Comandi, G.; Catastini, G.

    2000-06-01

    `Galileo Galilei' (GG) is a proposal for a small, low-orbit satellite devoted to testing the equivalence principle (EP) of Galileo, Newton and Einstein. The GG report on the phase A study recently carried out with funding from ASI (Agenzia Spaziale Italiana) concluded that GG can test the equivalence principle to 1 part in 1017 at room temperature. The main novelty is to modulate the expected differential signal of an EP violation at the spin rate of the spacecraft (2 Hz). Compared with other experiments, the modulation frequency is increased by more than a factor of 104, thus reducing 1/f (low-frequency) electronic and mechanical noise. The challenge for an EP test in space is to improve over the sensitivity of ground-based experiments (about 1 part in 1012) by many orders of magnitude, so as to deeply probe a so far totally unexplored field; doing that with more than one pair of bodies is an unnecessary complication. For this reason GG is now proposed with a single pair of test masses. At present the best and most reliable laboratory-controlled tests of the equivalence principle have been achieved by the `Eöt-Wash' group with small test cylinders arranged on a torsion balance placed on a turntable which provides the modulation of the signal (a 1-2 h rotation period). The torsion balance is not a suitable instrument in space. We have designed and built the GGG (`GG on the Ground') prototype. It is made of coaxial test cylinders weakly coupled (via mechanical suspensions) and quickly rotating (6 Hz achieved so far); in addition, it is well suited to be flown in space - where the driving signal is about three orders of magnitude stronger and the absence of weight is very helpful - inside the coaxial, co-rotating GG cylindrical spacecraft. The GGG apparatus is now operational. Preliminary measurement data indicate that weakly coupled, fast-spinning macroscopic rotors can be a suitable instrument to detect small differential effects. Rotation (up to 6 Hz so far) is

  10. Memoria e ripetizione come strategie argomentative nelle testimonianze di Galileo Galilei al Santo Offizio

    Directory of Open Access Journals (Sweden)

    Patrizia Collina Bastianetto

    2011-10-01

    Full Text Available Resumo: O presente trabalho pretende focalizar o percurso discursivo dos depoimentos do astrônomo italiano Galileu Galilei, no julgamento a que foi submetido em Roma, pela Inquisição, em 1633. Visa-se apresentar e analisar alguns dos recursos retóricos e argumentativos adotados em seus depoimentos com a finalidade de defender-se da acusação de heresia.Palavras-chave: Galileu Galilei; argumentação; memória; repetição.Abstract: Le riflessioni che seguono riprendono il percorso discorsivo dell’astronomo Galileo Galilei durante il processo a cui fu sottoposto dall’Inquisizione nel 1633. Presentiamo e analizziamo alcune strategie argomentative adottate dallo scienziato nelle sue testimonianze per difendersi dall’accusa di sospetto di eresia.Parole chiave: Galileo Galilei; argomentazione; memoria; ripetizione.Keywords: Galileo Galilei; argumentation; memory; repetition.

  11. Galileo's eye: a new vision of the senses in the work of Galileo Galilei.

    Science.gov (United States)

    Piccolino, Marco; Wade, Nicholas J

    2008-01-01

    Reflections on the senses, and particularly on vision, permeate the writings of Galileo Galilei, one of the main protagonists of the scientific revolution. This aspect of his work has received scant attention by historians, in spite of its importance for his achievements in astronomy, and also for the significance in the innovative scientific methodology he fostered. Galileo's vision pursued a different path from the main stream of the then contemporary studies in the field; these were concerned with the dioptrics and anatomy of the eye, as elaborated mainly by Johannes Kepler and Christoph Scheiner. Galileo was more concerned with the phenomenology rather than with the mechanisms of the visual process. His general interest in the senses was psychological and philosophical; it reflected the fallacies and limits of the senses and the ways in which scientific knowledge of the world could be gathered from potentially deceptive appearances. Galileo's innovative conception of the relation between the senses and external reality contrasted with the classical tradition dominated by Aristotle; it paved the way for the modern understanding of sensory processing, culminating two centuries later in Johannes Müller's elaboration of the doctrine of specific nerve energies and in Helmholtz's general theory of perception.

  12. Il compasso geometrico e militare di Galileo Galilei testi, annotazioni e disputa negli scritti di G. Galilei, M. Bernegger e B. Capra

    CERN Document Server

    1992-01-01

    Il compasso geometrico e militare / di Roberto Vergara Caffarelli - Le operazioni del compasso geometrico e militare / Galileo Galilei - Annotazioni / Mattia Bernaggeri - Usus et fabrica circini cuiusdam proportionis / Baldassarre Capra - Difesa contro alle calunnie ed imposture di Baldassar Capra.

  13. Seeds of a Tychonic Revolution: Telescopic Observations of the Stars by Galileo Galilei and Simon Marius

    Science.gov (United States)

    Graney, Christopher M.

    2010-03-01

    Because early telescopic astronomers did not understand the spurious nature of star images formed by their telescopes, their observations of the stars yielded data that apparently confirmed the geocentric Tychonic world system. Both Galileo Galilei (1564-1642) and Simon Marius (1570-1624) obtained such data. Galileo backed Nicholas Copernicus (1473-1543) despite his data. Marius supported Tycho Brahe (1546-1601) on the basis of his data.

  14. Galileo satellite antenna modeling

    Science.gov (United States)

    Steigenberger, Peter; Dach, Rolf; Prange, Lars; Montenbruck, Oliver

    2015-04-01

    The space segment of the European satellite navigation system Galileo currently consists of six satellites. Four of them belong to the first generation of In-Orbit Validation (IOV) satellites whereas the other two are Full Operational Capability (FOC) satellites. High-precision geodetic applications require detailed knowledge about the actual phase center of the satellite and receiver antenna. The deviation of this actual phase center from a well-defined reference point is described by phase center offsets (PCOs) and phase center variations (PCVs). Unfortunately, no public information is available about the Galileo satellite antenna PCOs and PCVs, neither for the IOV, nor the FOC satellites. Therefore, conventional values for the IOV satellite antenna PCOs have been adopted for the Multi-GNSS experiment (MGEX) of the International GNSS Service (IGS). The effect of the PCVs is currently neglected and no PCOs for the FOC satellites are available yet. To overcome this deficiency in GNSS observation modeling, satellite antenna PCOs and PCVs are estimated for the Galileo IOV satellites based on global GNSS tracking data of the MGEX network and additional stations of the legacy IGS network. Two completely independent solutions are computed with the Bernese and Napeos software packages. The PCO and PCV values of the individual satellites are analyzed and the availability of two different solutions allows for an accuracy assessment. The FOC satellites are built by a different manufacturer and are also equipped with another type of antenna panel compared to the IOV satellites. Signal transmission of the first FOC satellite has started in December 2014 and activation of the second satellite is expected for early 2015. Based on the available observations PCO estimates and, optionally PCVs of the FOC satellites will be presented as well. Finally, the impact of the new antenna model on the precision and accuracy of the Galileo orbit determination is analyzed.

  15. Experiments on buoyancy and surface tension following Galileo Galilei

    Science.gov (United States)

    Straulino, S.; Gambi, C. M. C.; Righini, A.

    2011-01-01

    We analyze passages of Galileo's writings on aspects of floating. Galileo encountered peculiar effects such as the "floating" of light objects made of dense material and the creation of large drops of water that were difficult to explain because they are related to our current understanding of surface tension. Even though Galileo could not understand the phenomenon, his proposed explanations and experiments are interesting from an educational point of view. We replicate the experiment on water and wine that was described by Galileo in his Two New Sciences.

  16. `Galileo Galilei' flight experiment on the equivalence principle with field emission electric propulsion

    Science.gov (United States)

    Nobili, Anna M.; Bramanti, Donato; Catastini, Giuseppe

    1996-11-01

    An experiment to test the equivalence of inertial to gravitational (passive) mass in space offers two main advantages: a signal about a factor of a thousand larger than on Earth and the possibility of exploiting the absence of weight. `Galileo Galilei' (GG) is a small satellite mission currently under study in Italy with the financial support of ASI (Agenzia Spaziale Italiana). The mission concerns a small, low Earth satellite (0264-9381/13/11A/028/img1 total mass, 0264-9381/13/11A/028/img2 altitude) with two objectives. One is scientific, in the field of fundamental physics, and the other technological within the framework of spacecraft propulsion and drag compensation. The scientific goal is to test the equivalence principle to one part in 0264-9381/13/11A/028/img3, four orders of magnitude better than the best ground results. The technological goal is a full, comprehensive test of FEEP (field emission electric propulsion) thrusters for accurate drag compensation, a technology developed in Europe by the ESA (European Space Agency) which is likely to become an essential component of all space experiments which require measurement of small forces. The GG experiment is based on novel concepts and does not require low temperatures.

  17. The ``Galileo Galilei'' (GG) Project: Testing the Equivalence Principle in Space and on Earth

    Science.gov (United States)

    Nobili, A. M.; Bramanti, D.; Polacco, E.; Catastini, G.; Anselmi, A.; Portigliotti, S.; Lenti, A.; Severi, A.

    ``GALILEO GALILEI'' (GG) is a proposal for a small, low orbit satellite devoted to testing the Equivalence Principle (EP) of Galileo, Newton and Einstein to 1 part in 1017. At the end of 1997 GG has been selected and funded by ASI (Agenzia Spaziale Italiana) for a 1-year Phase A study. The main novelty of GG is that the concentric hollow test cylinders whose relative motion (in the plane perpendicular to the spin axis) would be affected by an EP violation, spin together with the read-out capacitance sensors placed in between them. The nominal spin rate is 2 Hz, and this is the frequency at which the putative EP violation signal is modulated by the sensors. As compared to other experiments the modulation frequency is increased by more than a factor 104, thus reducing 1/f (low frequency) electronic and mechanical noise. GG will have FEEP ion thrusters for drag compensation. The required amount of propellant is of a few grams only. The experiment works at room temperature. To demonstrate the feasibility of the space experiment a payload prototype for EP testing on the ground (GGG - GG on the Ground) is under development in the laboratories of Laben. The challenge in this field is to fly an experiment able to improve by many orders of magnitude the current best ground sensitivity (≅10-12). This requires spurious relative motions of the test bodies to be greatly reduced, leaving them essentially motionless. Doing that with more than one pair of bodies appears to be an unnecessary complication. This is why GG is now proposed with a single pair of test masses. Information, research papers and photographs of the ground apparatus are available on the Web (http://tycho.dm.unipi.it/nobili)

  18. The dark side of the Scientific Revolution. The Biblical interpretation in Galileo Galilei and Isaac Newton

    Directory of Open Access Journals (Sweden)

    Francesco Fiorentino

    2015-11-01

    Full Text Available This contribution investigates a hidden and surely singular – but far from marginal – aspect of the Scientific Revolution of the 17th century, in other words the interpretation of the Holy Scriptures. First of all, this work analyzes the situation immediately before the advent of the fathers of the 17th Century Scientific Revolution like Galileo Galilei and Isaac Newton, starting from the Council of Trent. This reconstruction aims to throw light on the particular way that Galileo and Newton intended to approach the interpretation of the Holy Scriptures with respect to the main tendencies of the Catholic Reformation of biblical hermeneutics. Their way is important both in itself and in relation to the Scientific Revolution. In itself because Galileo and Newton elaborate original theories that are not entirely in agreement with the predominant views and that are decidedly no less interesting than their pure scientific theories. In relation to the Scientific Revolution because the interpretation of the Holy Scriptures is addressed in an original fashion by both Galileo and Newton, also with the intent of facilitating the spread and approval of their own scientific theories in their respective socio-cultural environments. The primacy of nature is not manifested only in contrast to and outside the book of Scriptures, but conditions the Book of Scriptures, locating it within a precise cultural perspective and religious sense that are by no means contrary to Galileo and Newton’s views.

  19. The stars of Galileo Galilei and the universal knowledge of Athanasius Kircher

    CERN Document Server

    Buonanno, Roberto

    2014-01-01

    In this fascinating book, the author traces the careers, ideas, discoveries, and inventions of two renowned scientists, Athanasius Kircher and Galileo Galilei, one a Jesuit, the other a sincere man of faith whose relations with the Jesuits deteriorated badly. The Author documents Kircher’s often intuitive work in many areas, including translating the hieroglyphs, developing sundials, and inventing the magic lantern, and explains how Kircher was a forerunner of Darwin in suggesting that animal species evolve. Galileo’s work on scales, telescopes, and sun spots is mapped and discussed, and care is taken to place his discoveries within their cultural environment. While Galileo is without doubt the “winner” in the comparison with Kircher, the latter achieved extraordinary insights by unconventional means. For all Galileo’s fine work, the author believes that scientists do need to regain the power of dreaming, vindicating Kirchner’s view.

  20. Galileo Galilei-GG”: design, requirements, error budget and significance of the ground prototype

    Science.gov (United States)

    Nobili, A. M.; Bramanti, D.; Comandi, G. L.; Toncelli, R.; Polacco, E.; Chiofalo, M. L.

    2003-11-01

    Galileo Galilei-GG” is a proposed experiment in low orbit around the Earth aiming to test the equivalence principle to the level of 1 part in 10 17 at room temperature. A unique feature of GG, which is pivotal to achieve high accuracy at room temperature, is fast rotation in supercritical regime around the symmetry axis of the test cylinders, with very weak coupling in the plane perpendicular to it. Another unique feature of GG is the possibility to fly 2 concentric pairs of test cylinders, the outer pair being made of the same material for detection of spurious effects. GG was originally designed for an equatorial orbit. The much lower launching cost for higher inclinations has made it worth redesigning the experiment for a sun-synchronous orbit. We report the main conclusions of this study, which confirms the feasibility of the original goal of the mission also at high inclination, and conclude by stressing the significance of the ground based prototype of the apparatus proposed for space.

  1. 'Galileo Galilei (GG) on the Ground-GGG': experimental results and perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Comandi, G.L.; Nobili, A.M.; Bramanti, D.; Toncelli, R.; Polacco, E.; Chiofalo, M.L

    2003-11-10

    The GGG differential accelerometer is made of concentric coaxial test cylinders weakly coupled in the horizontal plane and spinning in supercritical regime around their symmetry axis. GGG is built as a full scale ground based prototype for the proposed 'Galileo Galilei-GG' space experiment aiming to test the equivalence principle (EP) to 10{sup -17} at room temperature. We report measured Q values of 95000 at 1.4 Hz, and expect even better ones at typical spin frequencies of a few Hz. An EP violation signal in the field of the Sun would appear as a low frequency displacement in the horizontal plane of the laboratory, and it can be separated out from a much larger whirl motion of the test masses at their natural differential frequency. So far we have managed to reduce the amplitude of this whirl to about 0.1 {mu}m. We discuss how to improve these results in view of the very high accuracy GG experiment in space, and/or to reach a 10{sup -13} sensitivity in the lab which would allow us to either confirm or rule out recent predictions of violation to this level.

  2. Galileo Galilei (GG) on the Ground-GGG”: experimental results and perspectives

    Science.gov (United States)

    Comandi, G. L.; Nobili, A. M.; Bramanti, D.; Toncelli, R.; Polacco, E.; Chiofalo, M. L.

    2003-11-01

    The GGG differential accelerometer is made of concentric coaxial test cylinders weakly coupled in the horizontal plane and spinning in supercritical regime around their symmetry axis. GGG is built as a full scale ground based prototype for the proposed “Galileo Galilei-GG” space experiment aiming to test the equivalence principle (EP) to 10 -17 at room temperature. We report measured Q values of 95000 at 1.4 Hz, and expect even better ones at typical spin frequencies of a few Hz. An EP violation signal in the field of the Sun would appear as a low frequency displacement in the horizontal plane of the laboratory, and it can be separated out from a much larger whirl motion of the test masses at their natural differential frequency. So far we have managed to reduce the amplitude of this whirl to about 0.1 μm. We discuss how to improve these results in view of the very high accuracy GG experiment in space, and/or to reach a 10 -13 sensitivity in the lab which would allow us to either confirm or rule out recent predictions of violation to this level.

  3. The enigma of Galileo's eyesight: some novel observations on Galileo Galilei's vision and his progression to blindness.

    Science.gov (United States)

    Watson, Peter G

    2009-01-01

    Galileo Galilei became blind. Before this happened he revealed that his left eye had always had less than perfect vision. A study of his written works, his handwriting, and the originals of the portraits undertaken during his lifetime indicate that this probably was the case. These portraits suggest that his left eye tended to lose fixation and that, at the age of 60, he suffered from a mucocoele of the right frontal sinus; but these conditions would not have caused blindness. Considering the systemic diseases from which he suffered over his lifetime, he could possibly have had a long standing uveitis with secondary pupillary block glaucoma, common in those with the group of conditions classified as sero-negative arthropathies. Posterior scleritis with secondary glaucoma is less likely. If either of these were the cause, then the disease was probably triggered by a well-documented, severe acute illness as a young adult, the inflammation being localized to the eye as a result of severe recurrent conjunctival infections in his youth. The intermittent nature of the visual loss, the normal appearance of the cornea and pupils in his portraits, the absence of any evidence of inflammatory joint disease, the presence of halos, and the severe nature of the pain-combined with the high level of visual acuity in between attacks and its persistence until the last few weeks of vision means that angle-closure glaucoma must also be considered. These suggestions might be confirmed or refuted by studying his remains. Application has been made for this to be done.

  4. 'Galileo Galilei-GG': design, requirements, error budget and significance of the ground prototype

    Energy Technology Data Exchange (ETDEWEB)

    Nobili, A.M.; Bramanti, D.; Comandi, G.L.; Toncelli, R.; Polacco, E.; Chiofalo, M.L

    2003-11-10

    'Galileo Galilei-GG' is a proposed experiment in low orbit around the Earth aiming to test the equivalence principle to the level of 1 part in 10{sup 17} at room temperature. A unique feature of GG, which is pivotal to achieve high accuracy at room temperature, is fast rotation in supercritical regime around the symmetry axis of the test cylinders, with very weak coupling in the plane perpendicular to it. Another unique feature of GG is the possibility to fly 2 concentric pairs of test cylinders, the outer pair being made of the same material for detection of spurious effects. GG was originally designed for an equatorial orbit. The much lower launching cost for higher inclinations has made it worth redesigning the experiment for a sun-synchronous orbit. We report the main conclusions of this study, which confirms the feasibility of the original goal of the mission also at high inclination, and conclude by stressing the significance of the ground based prototype of the apparatus proposed for space.

  5. Dynamical response of the Galileo Galilei on the ground rotor to test the equivalence principle: Theory, simulation, and experiment. II. The rejection of common mode forces

    Science.gov (United States)

    Comandi, G. L.; Toncelli, R.; Chiofalo, M. L.; Bramanti, D.; Nobili, A. M.

    2006-03-01

    "Galileo Galilei on the ground" (GGG) is a fast rotating differential accelerometer designed to test the equivalence principle (EP). Its sensitivity to differential effects, such as the effect of an EP violation, depends crucially on the capability of the accelerometer to reject all effects acting in common mode. By applying the theoretical and simulation methods reported in Part I of this work, and tested therein against experimental data, we predict the occurrence of an enhanced common mode rejection of the GGG accelerometer. We demonstrate that the best rejection of common mode disturbances can be tuned in a controlled way by varying the spin frequency of the GGG rotor.

  6. Galileo

    CERN Document Server

    Heilbron, John

    2010-01-01

    Four hundred years ago, in 1610, Galileo published the Siderius nuncius, or Starry Messenger, a 'hurried little masterpiece' in John Heilbron's words. Presenting to the world his remarkable observations using the recently invented telescope - of the craters of the moon, and the satellites of Jupiter, observations that forced changes to perceptions of the perfection of the heavens and the centrality of the Earth - the appearance of the little book is regarded as oneof the greatest moments in the history of science. It was also a point of change in the life of Galileo himself, propelling him fro

  7. Jovian discoveries; how Galileo explored the Jovian system fifteen years ago

    NARCIS (Netherlands)

    Willems, T.

    2011-01-01

    Ever since the famous astronomer Galileo Galilei improved his telescope making it possible to look further into space, people have been staring through telescopes into the far distance in search of new worlds. In January 1610 Galilei discovered the four biggest satellites of Jupiter: Io, Europa, Gan

  8. Jovian discoveries; how Galileo explored the Jovian system fifteen years ago

    NARCIS (Netherlands)

    Willems, T.

    2011-01-01

    Ever since the famous astronomer Galileo Galilei improved his telescope making it possible to look further into space, people have been staring through telescopes into the far distance in search of new worlds. In January 1610 Galilei discovered the four biggest satellites of Jupiter: Io, Europa, Gan

  9. GNSS global navigation satellite systems : GPS, GLONASS, Galileo, and more

    CERN Document Server

    Hofmann-Wellenhof, Bernhard; Wasle, Elmar

    2008-01-01

    This book is an extension to the acclaimed scientific bestseller "GPS - Theory and Practice". It covers Global Navigation Satellite Systems (GNSS) and includes the Russian GLONASS, the European system Galileo, and additional systems.

  10. The European Satellite Navigation System Galileo

    Institute of Scientific and Technical Information of China (English)

    G.W. Hein; T. Pany

    2003-01-01

    This paper starts with a brief discussion of the Galileo project status and with a description of the present Galileo architecture (space segment, ground segment, user segment). It focuses on explaining special features compared to the American GPS system. The presentation of the user segment comprises a discussion of the actual Galileo signal structure. The Galileo carrier frequency, modulation scheme and data rate of all 10 navigation signals are described as well as parameters of the search and rescue service. The navigation signals are used to realize three types of open services, the safety of life service, two types of commercial services and the public regulated service. The signal performance in terms of the pseudorange code error due to thermal noise and multipath is discussed as well as interference to and from other radionavigation services broadcasting in the E5 and E6 frequency band. The interoperability and compatibility of Galileo and GPS is realized by a properly chosen signal structures in E5a/L5 and E2-L1-E1 and compatible geodetic and time reference frames. Some new results on reciprocal GPS/Galileo signal degradation due to signal overlay are presented as well as basic requirements on the Galileo code sequences.

  11. UN ANÁLISIS DE LA RESISTENCIA DE MATERIALES A PARTIR DE LOS POSTULADOS DE “CONSIDERACIONES Y DEMOSTRACIONES MATEMÁTICAS SOBRE DOS NUEVAS CIENCIAS” DE GALILEO GALILEI

    OpenAIRE

    HÉCTOR E. JARAMILLO S.

    2011-01-01

    En este trabajo se presenta un análisis de los postulados realizados por Galileo Galilei en su libro ―Consideraciones y demostraciones matemáticas sobre dos nuevas ciencias‖, desde la óptica de los principios modernos de la Resistencia de Materiales. Igualmente se hace un análisis descriptivo y numérico de las proposiciones planteadas por Galileo, como casos particulares de aplicación. Se encontró que estos postulados guardan vigencia actualmen...

  12. Dynamical response of the Galileo Galilei on the ground rotor to test the equivalence principle: Theory, simulation, and experiment. I. The normal modes

    Science.gov (United States)

    Comandi, G. L.; Chiofalo, M. L.; Toncelli, R.; Bramanti, D.; Polacco, E.; Nobili, A. M.

    2006-03-01

    Recent theoretical work suggests that violation of the equivalence principle might be revealed in a measurement of the fractional differential acceleration η between two test bodies—of different compositions, falling in the gravitational field of a source mass—if the measurement is made to the level of η ≃10-13 or better. This being within the reach of ground based experiments gives them a new impetus. However, while slowly rotating torsion balances in ground laboratories are close to reaching this level, only an experiment performed in a low orbit around the Earth is likely to provide a much better accuracy. We report on the progress made with the "Galileo Galilei on the ground" (GGG) experiment, which aims to compete with torsion balances using an instrument design also capable of being converted into a much higher sensitivity space test. In the present and following articles (Part I and Part II), we demonstrate that the dynamical response of the GGG differential accelerometer set into supercritical rotation—in particular, its normal modes (Part I) and rejection of common mode effects (Part II)—can be predicted by means of a simple but effective model that embodies all the relevant physics. Analytical solutions are obtained under special limits, which provide the theoretical understanding. A simulation environment is set up, obtaining a quantitative agreement with the available experimental data on the frequencies of the normal modes and on the whirling behavior. This is a needed and reliable tool for controlling and separating perturbative effects from the expected signal, as well as for planning the optimization of the apparatus.

  13. Enhanced solar radiation pressure modeling for Galileo satellites

    Science.gov (United States)

    Montenbruck, O.; Steigenberger, P.; Hugentobler, U.

    2015-03-01

    This paper introduces a new approach for modeling solar radiation pressure (SRP) effects on Global Navigation Satellite Systems (GNSSs). It focuses on the Galileo In-Orbit Validation (IOV) satellites, for which obvious SRP modeling deficits can be identified in presently available precise orbit products. To overcome these problems, the estimation of empirical accelerations in the Sun direction (D), solar panel axis (Y) and the orthogonal (B) axis is complemented by an a priori model accounting for the contribution of the rectangular spacecraft body. Other than the GPS satellites, which comprise an almost cubic body, the Galileo IOV satellites exhibit a notably rectangular shape with a ratio of about 2:1 for the main body axes. Use of the a priori box model allows to properly model the varying cross section exposed to the Sun during yaw-steering attitude mode and helps to remove systematic once-per-revolution orbit errors that have so far affected the Galileo orbit determination. Parameters of a simple a priori cuboid model suitable for the IOV satellites are established from the analysis of a long-term set of GNSS observations collected with the global network of the Multi-GNSS Experiment of the International GNSS Service. The model is finally demonstrated to reduce the peak magnitude of radial orbit errors from presently 20 cm down to 5 cm outside eclipse phases.

  14. UN ANÁLISIS DE LA RESISTENCIA DE MATERIALES A PARTIR DE LOS POSTULADOS DE “CONSIDERACIONES Y DEMOSTRACIONES MATEMÁTICAS SOBRE DOS NUEVAS CIENCIAS” DE GALILEO GALILEI

    Directory of Open Access Journals (Sweden)

    HÉCTOR E. JARAMILLO S.

    2011-12-01

    Full Text Available En este trabajo se presenta un análisis de los postulados realizados por Galileo Galilei en su libro ―Consideraciones y demostraciones matemáticas sobre dos nuevas ciencias‖, desde la óptica de los principios modernos de la Resistencia de Materiales. Igualmente se hace un análisis descriptivo y numérico de las proposiciones planteadas por Galileo, como casos particulares de aplicación. Se encontró que estos postulados guardan vigencia actualmente y, aunque son muy básicos para la actualidad, no habrían sido formulados formalmente hasta este momento, sin embargo su importancia radica en su contribución al sentar las bases de la Resistencia de Materiales moderna.

  15. Estimation of satellite antenna phase center offsets for Galileo

    Science.gov (United States)

    Steigenberger, P.; Fritsche, M.; Dach, R.; Schmid, R.; Montenbruck, O.; Uhlemann, M.; Prange, L.

    2016-08-01

    Satellite antenna phase center offsets for the Galileo In-Orbit Validation (IOV) and Full Operational Capability (FOC) satellites are estimated by two different analysis centers based on tracking data of a global GNSS network. The mean x- and y-offsets could be determined with a precision of a few centimeters. However, daily estimates of the x-offsets of the IOV satellites show pronounced systematic effects with a peak-to-peak amplitude of up to 70 cm that depend on the orbit model and the elevation of the Sun above the orbital plane. For the IOV y-offsets, no dependence on the orbit model exists but the scatter strongly depends on the elevation of the Sun above the orbital plane. In general, these systematic effects are significantly smaller for the FOC satellites. The z-offsets of the two analysis centers agree within the 10-15 cm level, and the time series do not show systematic effects. The application of an averaged Galileo satellite antenna model obtained from the two solutions results in a reduction of orbit day boundary discontinuities by up to one third—even if an independent software package is used.

  16. Galileo perceptionist.

    Science.gov (United States)

    Sinico, Michele

    2012-01-01

    The present paper focuses on Galileo's conception of perception. I take as my starting point the interpretation of the Galilean text by Piccolino and Wade (2008, Perception 37 1312-1340): Galileo's eye: a new vision of the senses in the work of Galileo Galilei. Three points are discussed: the criticism of naive realism, the theoretical role of perceptual laws, and the distinction between different qualities of experience. The conclusions support an alternative interpretation which underscores the crucial role of phenomenology of perception in Galileo's epistemology.

  17. Galileo and the Movies

    Science.gov (United States)

    Olivotto, Cristina; Testa, Antonella

    2010-12-01

    We analyze the character of Galileo Galilei (1564-1642), one of the most famous scientists of all time, as portrayed in three significant movies: Luigi Maggi's Galileo Galilei (1909), Liliana Cavani's Galileo (1968), and Joseph Losey's Galileo (1975), the last one of which was based upon Bertolt Brecht's drama, Das Leben des Galilei (1947). We investigate the relationships between the main characteristics of these fictional Galileos and the most important twentieth-century Galilean historiographic models. We also analyze the veracity of the plots of these three movies and the role that historical and scientific consultants played in producing them. We conclude that connections between these three movies and Galilean historiographic models are far from evident, that other factors deeply influenced the representation of Galileo on the screen.

  18. Galileo's first images of Jupiter and the Galilean satellites

    Science.gov (United States)

    Belton, M.J.S.; Head, J. W.; Ingersoll, A.P.; Greeley, R.; McEwen, A.S.; Klaasen, K.P.; Senske, D.; Pappalardo, R.; Collins, G.; Vasavada, A.R.; Sullivan, R.; Simonelli, D.; Geissler, P.; Carr, M.H.; Davies, M.E.; Veverka, J.; Gierasch, P.J.; Banfield, D.; Bell, M.; Chapman, C.R.; Anger, C.; Greenberg, R.; Neukum, G.; Pilcher, C.B.; Beebe, R.F.; Burns, J.A.; Fanale, F.; Ip, W.; Johnson, T.V.; Morrison, D.; Moore, J.; Orton, G.S.; Thomas, P.; West, R.A.

    1996-01-01

    The first images of Jupiter, Io, Europa, and Ganymede from the Galileo spacecraft reveal new information about Jupiter's Great Red Spot (GRS) and the surfaces of the Galilean satellites. Features similar to clusters of thunderstorms were found in the GRS. Nearby wave structures suggest that the GRS may be a shallow atmospheric feature. Changes in surface color and plume distribution indicate differences in resurfacing processes near hot spots on lo. Patchy emissions were seen while Io was in eclipse by Jupiter. The outer margins of prominent linear markings (triple bands) on Europa are diffuse, suggesting that material has been vented from fractures. Numerous small circular craters indicate localized areas of relatively old surface. Pervasive brittle deformation of an ice layer appears to have formed grooves on Ganymede. Dark terrain unexpectedly shows distinctive albedo variations to the limit of resolution.

  19. Appunti sulle osservazioni telescopiche di Galilei

    Science.gov (United States)

    Vanin, Gabriele

    2001-01-01

    The author inspects the telescopic observations performed by Galileo Galilei beginning since 1609. In the first part he examines the attribution to Galileo of the instruments now in Florence in the Istituto e Museo di Storia della Scienza (IMSS). In the second part he considers the observative and optical analyses realized in this century about the telescopes. In the final part he exposes the observations carried out with an instrument very similar to those Galileo had, the "Project STAR" Scope. The author concludes the IMSS instruments represent very well those used by Galileo and, in particular, they are among the best utilized by Italian scientists. The author is also convinced since 1612 Galileo employed a telescope with 5" resolution power.

  20. Preliminary Analysis of a Novel SAR Based Emergency System for Earth Orbit Satellites using Galileo

    NARCIS (Netherlands)

    Gill, E.K.A.; Helderweirt, A.

    2010-01-01

    This paper presents a preliminary analysis of a novel Search and Rescue (SAR) based emergency system for Low Earth Orbit (LEO) satellites using the Galileo Global Navigation Satellite System (GNSS). It starts with a description of the space user SAR system including a concept description, mission ar

  1. GNSS--global navigation satellite systems: GPS, GLONASS, Galileo, and more

    National Research Council Canada - National Science Library

    Hofmann-Wellenhof, B; Lichtenegger, Herbert; Wasle, Elmar

    2008-01-01

    ... long period of insufficient maintenance with respect to the number of available satellites, a proper consideration in the book was also required. "GNSS - GPS, GLONASS, Galileo & more" - is this title correct? This simple question is not that easily to be answered. Following a definition as given in the document A/CONF.184/BP/4 on satellite navigatio...

  2. From Galileo to Newton

    CERN Document Server

    Hall, Alfred Rupert

    1982-01-01

    The near century (1630–1720) that separates the important astronomical findings of Galileo Galilei (1564–1642) and the vastly influential mathematical work of Sir Isaac Newton (1642–1727) represents a pivotal stage of transition in the history of science. Tracing the revolution in physics initiated by Galileo and culminating in Newton's achievements, this book surveys the work of Huygens, Leeuwenhoek, Boyle, Descartes, and others. 35 illustrations.

  3. Exploring Galileo's Telescope

    Science.gov (United States)

    Straulino, Samuele; Terzuoli, Alessandra

    2010-01-01

    In the first months of 2009, the International Year of Astronomy, the authors developed an educational project for middle-level students connected with the first astronomical discoveries that Galileo Galilei (1564-1642) made 400 years ago. The project included the construction of a basic telescope and the observation of the Moon. The project, if…

  4. Long-term evolution of navigation satellite orbits: GPS/GLONASS/GALILEO

    Science.gov (United States)

    Chao, C.; Gick, R.

    Earlier studies conducted a The Aerospace Corporation discovered that the GPSt Block II satellites placed in disposal orbits can eventually, perhaps in 20 to 40 years, reenter into the operating constellation. This is because the disposal orbits, while circular initially, evolve int o orbits with significant eccentricity mostly as the result of sun-moon gravitational perturbations. Options of minimizing the eccentricity growth include reducing initial eccentricity of the disposal orbit and inserting into an orbit with a favorable argument of perigee. A recent study was performed to examine whether the same long-term eccentricity evolution exists for the disposal orbits of other navigation satellite systems such as GLONASS and GALILEO. The non-operational GPS Block I satellites are included in the study as well, because the orbits are at 63.4 deg inclination, which is different from that of the GPS Block II satellites. Similar to the earlier studies, long-term perturbations and stability of these orbits were understood through analytical and numerical investigations. Two-hundred-year semi-analytic integration revealed interesting facts about the orbit stability. Initially near circular, these types of orbits may evolve into orbits with large eccentricity (as much as 0.7 over 150 years). Analytical approximations through doubly-averaged equations reveal that the cause is due to the resonance induced by Sun/moon and J2 secular perturbations. A total of 113 non-operational GLONASS satellites and upper stages and 10 GPS/Block I satellites were propagated for 200 years using a high-precision semi-analytical propagator (MEANPROP). Results show that the GLONASS satellites will start to enter the operating GPS constellation after 40 years. The uncovered resonance effect is strongly dependent on o bit inclination and altitude. The effect becomes morer pronounced for GALILEO orbits due to a higher altitude, 3000 km above GPS. Strategies to minimize the significant

  5. Assess the Galileo IOV satellites measurement accuracy%Galileo在轨验证卫星的性能研究

    Institute of Scientific and Technical Information of China (English)

    宋玉石; 张云; 袁国良

    2015-01-01

    Galileo卫星导航系统当前处于在轨验证阶段,对在轨验证卫星性能的分析能洞察Galileo系统的性能。本文从信噪比、伪距多路径误差和单点定位精度等方面进行分析并同GPS卫星进行对比,在计算伪距多路径误差时本文提出了能简化计算的处理四频信号伪距多路径误差的数学模型。通过分析可知Galileo 在轨验证卫星的信号强度要强于GPS信号,Galileo信号的多路径误差小于GPS信号的多路径误差并且 Galileo/GPS 组合系统的定位精度也优于GPS系统。%The Galileo satellite navigation system is in In-Orbit Validation phase currently and the analysis of the IOV satellites'smeasurements provides insight on the performanceof the Galileo system.In order to compare the positioning performance with GPS system,this paper analyzes potentialities of the Galileo system from SNR, multipath error and the accuracy of single point positioning.At the same time,this research supplements the algorithm of calculating the multipath error. The experiment results showed thatGalileo IOV satellites'ssignal strength is stronger than GPS satellites.Galileo IOV satellites'smultipath error is smaller than GPS satellites.Thepositioning accuracy of combined Galileo/GPSsystemis better than GPS system.

  6. Positioning performance improvements with European multiple-frequency satellite navigation - Galileo

    Science.gov (United States)

    Ji, Shengyue

    2008-10-01

    The rapid development of Global Positioning System has demonstrated the advantages of satellite based navigation systems. In near future, there will be a number of Global Navigation Satellite System (GNSS) available, i.e. modernized GPS, Galileo, restored GLONASS, BeiDou and many other regional GNSS augmentation systems. Undoubtedly, the new GNSS systems will significantly improve navigation performance over current GPS, with a better satellite coverage and multiple satellite signal bands. In this dissertation, the positioning performance improvement of new GNSS has been investigated based on both theoretical analysis and numerical study. First of all, the navigation performance of new GNSS systems has been analyzed, particularly for urban applications. The study has demonstrated that Receiver Autonomous Integrity Monitoring (RAIM) performance can be significantly improved with multiple satellite constellations, although the position accuracy improvement is limited. Based on a three-dimensional urban building model in Hong Kong streets, it is found that positioning availability is still very low in high-rising urban areas, even with three GNSS systems. On the other hand, the discontinuity of navigation solutions is significantly reduced with the combined constellations. Therefore, it is possible to use cheap DR systems to bridge the gaps of GNSS positioning, with high accuracy. Secondly, the ambiguity resolution performance has been investigated with Galileo multiple frequency band signals. The ambiguity resolution performance of three different algorithms is compared, including CAR, ILS and improved CAR methods (a new method proposed in this study). For short baselines, with four frequency Galileo data, it is highly possible to achieve reliable single epoch ambiguity resolution, when the carrier phase noise level is reasonably low (i.e. less than 6mm). For long baselines (up to 800 km), the integer ambiguity can be determined within 1 min on average. Ambiguity

  7. On the Accuracy of Galileo's Observations

    CERN Document Server

    Graney, Christopher M

    2008-01-01

    Galileo Galilei had sufficient skill as an observer and instrument builder to be able to measure the positions and apparent sizes of objects seen through his telescopes to an accuracy of 2" or better. However, Galileo had no knowledge of wave optics, so when he was measuring stellar apparent sizes he was producing very accurate measurements of diffraction artifacts and not physical bodies.

  8. Time variable gravity retrieval and treatment of temporal aliasing using optical two-way links between GALILEO and LEO satellites

    Science.gov (United States)

    Hauk, Markus; Pail, Roland; Murböck, Michael; Schlicht, Anja

    2016-04-01

    For the determination of temporal gravity fields satellite missions such as GRACE (Gravity Recovery and Climate Experiment) or CHAMP (Challenging Minisatellite Payload) were used in the last decade. These missions improved the knowledge of atmospheric, oceanic and tidal mass variations. The most limiting factor of temporal gravity retrieval quality is temporal aliasing due to the undersampling of high frequency signals, especially in the atmosphere and oceans. This kind of error causes the typical stripes in spatial representations of global gravity fields such as from GRACE. As part of the GETRIS (Geodesy and Time Reference in Space) mission, that aims to establish a geodetic reference station and precise time- and frequency reference in space by using optical two-way communication links between geostationary (GEO) and low Earth orbiting (LEO) satellites, a possible future gravity field mission can be set up. By expanding the GETRIS space segment to the global satellite navigation systems (GNSS) the optical two-way links also connect the GALILEO satellites among themselves and to LEO satellites. From these links between GALILEO and LEO satellites gravitational information can be extracted. In our simulations inter-satellite links between GALILEO and LEO satellites are used to determine temporal changes in the Earth's gravitational field. One of the main goals of this work is to find a suitable constellation together with the best analysis method to reduce temporal aliasing errors. Concerning non-tidal aliasing, it could be shown that the co-estimation of short-period long-wavelength gravity field signals, the so-called Wiese approach, is a powerful method for aliasing reduction (Wiese et al. 2013). By means of a closed loop mission simulator using inter-satellite observations as acceleration differences along the line-of-sight, different mission scenarios for GALILEO-LEO inter-satellite links and different functional models like the Wiese approach are analysed.

  9. Galileo: Power, Pride, and Profit. The Relative Influence of Realist, Ideational, and Liberal Factors on the Galileo Satellite Program

    Science.gov (United States)

    2009-01-31

    2004. 38 Lungu, “Power, Techno-Economics, and Transatlantic Relations.” 39 Serge Plattard, interviewed by author, Paris, France, June 11, 2004...20020401&spa ge=25&id=doi:&sid=ProQ_ss&genre=article& lang =en (accessed January 15, 2008). 10 Dee Ann Divis, “Military Role for Galileo Emerges,” GPS...article& lang =en (accessed January 15, 2008). Battrick, Bruce ed. Agenda 2007: A Document by the ESA Director General. Noordwijk, The Netherlands

  10. Civil Satellite Navigation System-Galileo%民用卫生导航系统——Galileo(伽利略)

    Institute of Scientific and Technical Information of China (English)

    张杏谷

    2001-01-01

    介绍了欧盟目前正在发展的全球卫星导航系统--Galileo,它是一个多国、民建、民控、民用系统,是美国GPS系统的强力竞争者.它将为提高全球卫星导航系统的民用精度和可靠性起积极的作用.

  11. BeiDou and Galileo, Two Global Satellite Navigation Systems in Final Phase of the Construction, Visibility and Geometry

    Directory of Open Access Journals (Sweden)

    Jacek Januszewski

    2016-09-01

    Full Text Available Spatial segment is one of three segments of each satellite navigation systems (SNS. Nowadays two SNSs, GPS and GLONASS, are fully operational, two next SNSs, BeiDou in China and Galileo in Europe, are in final phase of the construction. In the case of China system this segment will consist of 35 satellites with three types of orbits ? medium (MEO, geostationary (GEO and inclined geosynchronous (IGSO. As GEO and IGSO satellites can be used in China and Asia-Pacific region only, BeiDou MEO constellation with 27 fully operational satellites will be taken into account in this paper. The orbital planes of the Galileo constellation will be divided in “slots” that contains at least one operational satellite. The Galileo reference constellation has 24 nominal orbital positions or operational slots in MEO homogeneously distributed in 3 orbital planes; i.e. 8 slots equally spaced per plane. As the error of user’s position obtained from both systems depends on geometry factor DOP (Dilution Of Precision among other things the knowledge of the number of satellites visible by the user above given masking elevation angle Hmin and the distributions of DOP coefficient values, GDOP in particular, is very important. The lowest and the greatest number of satellites visible in open area by the observer at different latitudes for different Hmin, the percentage of satellites visible above angle H, distributions (in per cent of satellites azimuths and GDOP coefficient values for different Hmin for BeiDou and Galileo systems at different latitudes are presented in the paper.

  12. European initiative for a new generation of satellite navigation services - Galileo; Die europaeische Initiative fuer eine neue Generation von Satellitennavigationsdiensten - GALILEO

    Energy Technology Data Exchange (ETDEWEB)

    Tusk, S. [Bundesministerium fuer Verkehr, Bau- und Wohnungswesen, Berlin (Germany)

    2000-07-01

    The currently existing satellite navigation systems GPS and GLONASS have impressively demonstrated the possibilities of using satellite navigation; there are numerous civilian applications worldwide. However, both systems are controlled nationally and designed for military applications and cannot meet the basic requirements in terms of continuity, integrity and precision required for safety-relevant and sovereign applications. Therefore, the Federal Republic of Germany supports the activities initiated by the EU, which consist of - developing, first of all, technical augmentations to make the existing systems useable without delay also for applications involving exacting requirements (GNSS 1, EGNOS), - carrying out in parallel the definition phase for the development of a global, civilian satellite navigation system (GNSS 2, Galileo). (orig.) [German] Die bisher existierenden Satellitennavigationssysteme GPS und GLONASS haben die Einsatzmoeglichkeiten der Satellitennavigation in eindrucksvoller Weise demonstriert; weltweit haben sich zahlreiche zivile Anwendungen ergeben. Jedoch sind beide Systeme national kontrolliert, auf militaerische Anwendungen zugeschnitten und koennen die fuer sicherheitsrelevante und hoheitliche Anwendungen notwendigen Grundanforderungen nach Kontinuitaet, Integritaet und Praezision nicht garantieren. Daher unterstuetzt die Bundesrepublik Deutschland die von der EU eingeleiteten Aktivitaeten, die daraus bestehen - zunaechst die bestehenden Systeme durch technische Ergaenzungen kurzfristig auch fuer hohe Anforderungen stellende Anwendungen nutzbar zu machen (GNSS 1, EGNOS) - parallel dazu die Definitionsphase zum Aufbau eines globalen zivilen Satellitennavigationssystems (GNSS 2, GALILEO) durchzufuehren. (orig.)

  13. Test of the gravitational redshift with stable clocks in eccentric orbits: application to Galileo satellites 5 and 6

    CERN Document Server

    Delva, P; Bertone, S; Richard, E; Wolf, P

    2015-01-01

    In this paper we propose to use satellites Galileo~5 and~6 to perform a test of the gravitational redshift. The best test to date was performed with the Gravity Probe A experiment (1976) with an accuracy of $1.4\\times 10^{-4}$. Here we show that considering realistic noise and systematic effects, and thanks to a highly eccentric orbit, it is possible to improve the GP-A limit to an accuracy around $(3-4)\\times 10^{-5}$ after one year of integration of Galileo~5 and~6 data.

  14. Precise positioning with current multi-constellation Global Navigation Satellite Systems: GPS, GLONASS, Galileo and BeiDou.

    Science.gov (United States)

    Li, Xingxing; Zhang, Xiaohong; Ren, Xiaodong; Fritsche, Mathias; Wickert, Jens; Schuh, Harald

    2015-02-09

    The world of satellite navigation is undergoing dramatic changes with the rapid development of multi-constellation Global Navigation Satellite Systems (GNSSs). At the moment more than 70 satellites are already in view, and about 120 satellites will be available once all four systems (BeiDou + Galileo + GLONASS + GPS) are fully deployed in the next few years. This will bring great opportunities and challenges for both scientific and engineering applications. In this paper we develop a four-system positioning model to make full use of all available observations from different GNSSs. The significant improvement of satellite visibility, spatial geometry, dilution of precision, convergence, accuracy, continuity and reliability that a combining utilization of multi-GNSS brings to precise positioning are carefully analyzed and evaluated, especially in constrained environments.

  15. On a recent preliminary study for the measurement of the Lense-Thirring effect with the Galileo satellites

    CERN Document Server

    Iorio, Lorenzo

    2014-01-01

    It has been recently proposed to combine the node drifts of the future constellation of 27 Galileo spacecraft together with those of the existing LAGEOS-type satellites to improve the accuracy of the past and ongoing tests of the Lense-Thirring (LT) effect by removing the bias of a larger number of even zonal harmonics $J_{\\ell}$ than either done or planned so far. Actually, it seems a difficult goal to be realistically achieved for a number of reasons. First, the LT range signature of a Galileo-type satellite is as little as $0.5$ mm over 3-days arcs, corresponding to a node rate of just $\\dot\\Omega_{\\rm LT}=2$ milliarcseconds per year (mas yr$^{-1}$). Some tesseral and sectorial ocean tides such as $K_1,K_2$ induce long-period harmonic node perturbations with frequencies which are integer multiples of the extremely slow Galileo's node rate $\\dot\\Omega$ completing a full cycle in about 40 yr. Thus, over time spans $T$ of some years they would act as superimposed semi-secular aliasing trends. Since the coeffi...

  16. POD improvements of GALILEO satellites through the measurement of their non-gravitational accelerations by means of an onboard accelerometer

    Science.gov (United States)

    Peron, Roberto; Lucchesi, David M.; Santoli, Francesco; Iafolla, Valerio; Fiorenza, Emiliano; Lefevre, Carlo; Lucente, Marco; Magnafico, Carmelo; Kalarus, Maciej; Zielinski, Janusz

    2016-04-01

    The Precise Orbit Determination (POD) of the satellites of the Global Navigation Satellite Systems (GNSS) represents the basic prerequisite in order to provide refined ephemerides for their orbit, aimed at providing a precise and accurate positioning on the Earth. An important factor that impacts negatively in the POD of these satellites is the limited modeling of the accelerations produced by the non-gravitational accelerations. These, indeed, are subtle and generally complex to model properly, especially in the case of a complex in shape spacecraft, with solar panels and antennae for microwave link and the mutual shadowing effects among the many surfaces involved. We have to notice that their modeling has an important impact in the determination of a number of geophysical parameters of interest, such as stations coordinates, Earth's geocenter and orientation parameters. In the case of GNSS satellites, the main NGP acceleration is the one produced by the direct solar radiation pressure, with non-negligible contributions due to Earth's albedo, thermal effects and power radiated by the antennae. The models developed so far for these perturbative effects have shown many limits, as pointed out in the literature. Currently, the models developed for the NGPs are mainly based on empirical blind models (with the goal of absorb unknowns quantities) and more recently with the use of wing-box models, that try to provide a finite-elements approach to the modeling. The European Space Agency (ESA) - in the context of the development of the GALILEO constellation, and especially in view of the next generation of GALILEO spacecraft - besides being interested in possible improvements of the NGPs models, is also envisaging the use of an onboard accelerometer to directly measure them in order to improve the POD of each spacecraft of the constellation. We have been involved in this study by means of a proposal to ESA denominated GALileo and ACcelerometry (GALAC) led by the Space

  17. Scaling Laws in Galileo: An Educational Proposal

    Science.gov (United States)

    Straulino, S.

    2011-01-01

    In his "Two New Sciences" Galileo Galilei deals with the strength of objects, discussing how it changes with size. Our daily life offers many examples of effects due to change of dimensions and sometimes the consequences are unintuitive. This subject is really interesting for secondary school students and it can be presented through simple…

  18. Scaling Laws in Galileo: An Educational Proposal

    Science.gov (United States)

    Straulino, S.

    2011-01-01

    In his "Two New Sciences" Galileo Galilei deals with the strength of objects, discussing how it changes with size. Our daily life offers many examples of effects due to change of dimensions and sometimes the consequences are unintuitive. This subject is really interesting for secondary school students and it can be presented through simple…

  19. Experimental Results for the Multipath Performance of Galileo Signals Transmitted by GIOVE-A Satellite

    Directory of Open Access Journals (Sweden)

    Andrew Simsky

    2008-01-01

    Full Text Available Analysis of GIOVE-A signals is an important part of the in-orbit validation phase of the Galileo program. GIOVE-A transmits the ranging signals using all the code modulations currently foreseen for the future Galileo and provides a foretaste of their performance in real-life applications. Due to the use of advanced code modulations, the ranging signals of Galileo provide significant improvement of the multipath performance as compared to current GPS. In this paper, we summarize the results of about 1.5 years of observations using the data from four antenna sites. The analysis of the elevation dependence of averaged multipath errors and the multipath time series for static data indicate significant suppression of long-range multipath by the best Galileo codes. The E5AltBOC signal is confirmed to be a multipath suppression champion for all the data sets. According to the results of the observations, the Galileo signals can be classified into 3 groups: high-performance (E5AltBOC, L1A, E6A, medium-performance (E6BC, E5a, E5b and an L1BC signal, which has the lowest performance among Galileo signals, but is still better than GPS-CA. The car tests have demonstrated that for kinematic multipath the intersignal differences are a lot less pronounced. The phase multipath performance is also discussed.

  20. Galileo's Telescope and the Birth of Space Science

    Science.gov (United States)

    van Helden, A.

    2002-01-01

    The age of telescopic astronomy began in December 1609, when Galileo Galilei (1564-1642) began the first telescopic astronomical research project, an extended series of observations of the Moon. Over the next 18 months, he discovered the earth-like nature of the Moon, four satellites of Jupiter, the strange appearances of Saturn, the phases of Venus, and sunspots. His discoveries cut at the roots of the Aristotelian cosmological system with its central, corrupt, Earth and perfect heavens; and they provided important evidence for the Copernican heliocentric system. The instruments that provided the turning point in this great transition were by modern standards exceedingly primitive, and there is no question about the fact that Galileo must have been an exceptional observer to discover what he did. But he was also a great communicator. His scientific arguments for the new world system were models of logic and rigor; they were also rhetorical masterpieces. Galileo never needed a popularizer to bring his ideas to a wide audience. For that he paid a price.

  1. Design of Software IF Signal Simulator for Galileo Satellite Navigation System%Galileo 卫星导航系统单频模拟软件信号源的设计

    Institute of Scientific and Technical Information of China (English)

    史雨薇; 孟维晓; 张中兆; 邹德岳

    2012-01-01

    Research on Galileo satellite navigation system is significant, for Galileo is the only satellite navigation system under construction by Europe. Galileo signal simulator can provide not only a good simulation environment for design and test of Galileo receivers, but also a platform for verification of new techniques and new schemes of Galileo system. In this paper a software IF signal simulator for Galileo Satellite Navigation System in El frequency band designed on C++ platform is proposed. Based on mathematic model of IF signal and principle diagrams of the software IF signal simulator presented in this paper, the design is further divided into 5 functional parts, which are respectively pseudo-random code producing, navigation message generating, MBOC modulation of signal, simulation of environment error and quantification. The idea and the flow of the design are detailed presented as the key point. At last the validity of the design is demonstrated through the simulation results of frequency spectrum of output signal, capturing results and recovered data.%Galileo卫星导航系统作为欧洲唯一计划建设的卫星导航体系,对它的研究有着十分重要的意义.Galileo模拟信号源既可以为Galileo接收机的设计与测试提供良好的仿真环境,同时也可为Galileo系统新技术新方案的验证提供平台.本文针对Galileo E1频段信号提出了一种基于C++软件平台的中频模拟信号源设计框架.文章在给出中频信号数学模型及模拟软源的设计原理框图的基础上,进一步将设计按功能分为5部分,分别为伪随机码产生,导航电文生成,信号MBOC调制,环境和误差模拟以及信号量化部分,详细的给出前3部分设计思路与流程是本文的重点.最后通过输出信号频谱仿真结果、捕获验证结果以及数据恢复的验证结果证明了模拟软源设计的正确性.

  2. Origin, Bulk Chemical Composition and Physical Structure of the Galilean Satellites of Jupiter: A Post-Galileo Analysis

    Science.gov (United States)

    Prentice, A. J. R.

    1999-01-01

    The origin of Jupiter and the Galilean satellite system is examined in the light of the new data that has been obtained by the NASA Galileo Project. In particular, special attention is given to a theory of satellite origin which was put forward at the start of the Galileo Mission and on the basis of which several predictions have now been proven successful. These predictions concern the chemical composition of Jupiter's atmosphere and the physical structure of the satellites. According to the proposed theory of satellite origin, each of the Galilean satellites formed by chemical condensation and gravitational accumulation of solid grains within a concentric family of orbiting gas rings. These rings were cast off equatorially by the rotating proto-Jovian cloud (PJC which contracted gravitationally to form Jupiter some 4 1/2 billion years ago. The PJC formed from the gas and grains left over from the gas ring that had been shed at Jupiter's orbit by the contracting proto-solar cloud (PSC Supersonic turbulent convection provides the means for shedding discrete gas rings. The temperatures T (sub n) of the system of gas rings shed by the PSC and PJC vary with their respective mean orbital radii R (sub n) (n = 0, 1,2,...) according as T (sub n) proportional to R (sub n) (exp -0.9). If the planet Mercury condenses at 1640 K, so accounting for the high density of that planet via a process of chemical fractionation between iron and silicates, then T (sub n) at Jupiter's orbit is 158 K. Only 35% of the water vapour condenses out. Thus fractionation between rock and ice, together with an enhancement in the abundance of solids relative to gas which takes place through gravitational sedimentation of solids onto the mean orbit of the gas ring, ensures nearly equal proportions of rock and ice in each of Ganymede and Callisto. Io and Europa condense above the H20 ice point and consist solely of hydrated rock (h-rock). The Ganymedan condensate consists of h-rock and H20 ice. For

  3. Galileo IOV Satellite Signal Monitoring and Analyzing%Galileo IOV卫星导航信号的监测与分析

    Institute of Scientific and Technical Information of China (English)

    赵静; 解剑; 蔚保国

    2012-01-01

    通过11 m抛物面天线对Galileo IOV PFM导航卫星信号进行监测接收,分析其各个频点信号的功率谱特性,利用全向天线和Galileo接收机对E1信号进行捕获跟踪试验,测试Galileo IOV卫星信号的基本性能,为理解和掌握Galileo系统建设的发展状态提供帮助。

  4. Galileo and the magic numbers

    CERN Document Server

    Rosen, Sidney

    2014-01-01

    Sixteenth century Italy produced a genius who marked the world with his studies and hypotheses about mathematical, physical and astronomical truths. His father, musician Vincenzio Galilei said, "Truth is not found behind a man's reputation. Truth appears only when the answers to questions are searched out by a free mind. This is not the easy path in life but it is the most rewarding." Galileo challenged divine law and the physics of Aristotle, and questioned everything in search of truths. And it was through this quest for truth that he was able to establish a structure for modern science.

  5. Galileo's Instruments of Credit Telescopes, Images, Secrecy

    CERN Document Server

    Biagioli, Mario

    2006-01-01

    In six short years, Galileo Galilei went from being a somewhat obscure mathematics professor running a student boarding house in Padua to a star in the court of Florence to the recipient of dangerous attention from the Inquisition for his support of Copernicanism. In that brief period, Galileo made a series of astronomical discoveries that reshaped the debate over the physical nature of the heavens: he deeply modified the practices and status of astronomy with the introduction of the telescope and pictorial evidence, proposed a radical reconfiguration of the relationship between theology and a

  6. A novel emergency system for low earth orbit satellites using Galileo GNSS

    NARCIS (Netherlands)

    Gill, E.K.A.; Helderweirt, A.

    2010-01-01

    Low Earth Orbit (LEO) satellites have a limited direct contact time with the stations of their ground segment. This fundamentally constraints a timeliness reaction of the mission control center in case of emergency situations onboard the LEO spacecraft. To enable such a rapid reaction to emergency s

  7. N = 4 l-conformal Galilei superalgebra

    Science.gov (United States)

    Galajinsky, Anton; Masterov, Ivan

    2017-08-01

    An N = 4 supersymmetric extension of the l-conformal Galilei algebra is constructed. This is achieved by combining generators of spatial symmetries from the l-conformal Galilei algebra and those underlying the most general superconformal group in one dimension D (2 , 1 ; α). The value of the group parameter α is fixed from the requirement that the resulting superalgebra is finite-dimensional. The analysis reveals α = -1/2 thus reducing D (2 , 1 ; α) to OSp (4 | 2).

  8. Galileo in der Oper : Philip Glass und die Entwicklung der wissenschaftlichen Neugier

    OpenAIRE

    2012-01-01

    Im Blick auf seine künstlerische Motivation befragt, warum er eigentlich eine Oper über den frühneuzeitlichen Gelehrten Galileo Galilei komponiert habe, bekennt sich Philip Glass zu einem lebensbegleitenden Interesse und einer anhaltenden Faszination durch Galileis Persönlichkeit, die ihn schon seit frühester Kindheit angezogen und zu eigenen Experimenten angeregt habe. Offensichtlich lässt sich Glass’ Bewunderung für Galilei auf vielfältige Ursachen zurückführen, nicht zuletzt auf kindliche ...

  9. In-Orbit Trend Analysis of Galileo Satellites for Power Sources Degradation Estimation

    Directory of Open Access Journals (Sweden)

    Bard Frederic

    2017-01-01

    The results are in all cases better than the predictions, which is expected due to the usage of conservatives assumptions in the design to cover (for both IOV and FOC worst case scenario for the entire constellation. It should be noted that the FOC GSAT201 and GSAT202 batteries are degrading slightly faster than the 6 others FOC batteries identified GSAT203, GSAT204, GSAT205, GSAT206, GSAT208 and GSAT209, but still below predictions due to their peculiar unexpected orbit reached after launch (higher DoD up to 42% measured due to longer eclipses. These 2 satellites will require specific degradation monitoring.

  10. Galileo and Music: A Family Affair

    Science.gov (United States)

    Fabris, D.

    2011-06-01

    According to Viviani, Galileo's first biographer, the scientist was an excellent keyboard and lute player. In turn Vincenzo Galilei, father of the illustrious scientist, had been one of the most influential music theorist of his age and also a great composer and virtuoso of the lute. Galileo and his brother Michelangelo, born in 1575, inherited Vincenzo's duel skills, both in theory and practical music: Galileo's correspondences show indeed his competence in the music and in the lute playing; Michelagnolo, after being educated in part in Galileo's house in Padua, transferred to Germany in Munich, where he became a court lute player. Nevertheless, Galileo helped for the rest of his life not only his brother but also his nephews, as documented in dozen of family letters quite important to establish the central role of the music in Galileo's everyday life, a fact almost ignored by most modern biographers. The importance of music in Galileo's output and life has been first outlined by the historian of sciences Stillman Drake and by the musicologist Claude Palisca. After their studies starting in the 1960s there is a great belief that Vincenzo influenced his son Galileo, directing him towards experimentation. The aim of this paper, following the reconstruction of Galileo's soundscape proposed by Pierluigi Petrobelli, is to reexamine the surviving historical accounts on the musical passion and talent of Galileo and his family in the several houses where they performed music (in Florence, Padua, Munich, etc.) in particular on the lute, the instrument that was an important experimental tool for the scientist.

  11. The Galilean Satellites

    Science.gov (United States)

    1998-01-01

    This composite includes the four largest moons of Jupiter which are known as the Galilean satellites. The Galilean satellites were first seen by the Italian astronomer Galileo Galilei in 1610. Shown from left to right in order of increasing distance from Jupiter, Io is closest, followed by Europa, Ganymede, and Callisto.The order of these satellites from the planet Jupiter helps to explain some of the visible differences among the moons. Io is subject to the strongest tidal stresses from the massive planet. These stresses generate internal heating which is released at the surface and makes Io the most volcanically active body in our solar system. Europa appears to be strongly differentiated with a rock/iron core, an ice layer at its surface, and the potential for local or global zones of water between these layers. Tectonic resurfacing brightens terrain on the less active and partially differentiated moon Ganymede. Callisto, furthest from Jupiter, appears heavily cratered at low resolutions and shows no evidence of internal activity.North is to the top of this composite picture in which these satellites have all been scaled to a common factor of 10 kilometers (6 miles) per picture element.The Solid State Imaging (CCD) system aboard NASA's Galileo spacecraft acquired the Io and Ganymede images in June 1996, the Europa images in September 1996, and the Callisto images in November 1997.Launched in October 1989, the spacecraft's mission is to conduct detailed studies of the giant planet, its largest moons and the Jovian magnetic environment. The Jet Propulsion Laboratory, Pasadena, CA, manages the mission for NASA's Office of Space Science, Washington, DC.The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission

  12. Galileo's Observations of Neptune

    Science.gov (United States)

    Standish, E. M.

    2001-11-01

    In 1979, Stillman Drake and Charles Kowal found that the astronomer Galileo actually observed the planet Neptune in the years 1612 and 1613. Galileo's observing notebooks still exist and are preserved in the National Central Library in Florence, Italy. In them, one can see the discovery of the four large moons of Jupiter, and one can follow the subsequent work of Galileo as he improved his telescopes, charted the nightly positions of the satellites, and refined his ability to predict their future configurations. One sees his observing innovations and improving accuracies which seem to reach a crescendo just at the time of his observations of Neptune. Further scrutiny of Galileo's notebooks has revealed other intriguing observations. One is a probable fourth observation of Neptune which has a direct bearing upon present-day ephemerides. There are also observations of two other objects which, to this day, despite some effort, remain unidentified - possibly asteroids, comets, novae, or supernovae. More than of just historical interest, Galileo's work still has important implications for present-day astronomy. The research described in this talk was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

  13. Galileo, measurement of the velocity of light, and the reaction times.

    Science.gov (United States)

    Foschi, Renato; Leone, Matteo

    2009-01-01

    According to the commonly accepted view, Galileo Galilei devised in 1638 an experiment that seemed able to show that the velocity of light is finite. An analysis of archival material shows that two decades later members of the Florence scientific society Accademia del Cimento followed Galileo guidelines by actually attempting to measure the velocity of light and suggesting improvements. This analysis also reveals a fundamental difference between Galileo's and Florence academy's methodologies and that Galileo's experiment was, in some respects, a pioneering work affecting also the history of the psychology of perception.

  14. Galileo's Pendulum.

    Science.gov (United States)

    Erlichson, Herman

    1999-01-01

    Describes a laboratory activity in which students speculate about the extent to which Galileo actually performed an experiment to determine that all pendulums of a given length have the same period, independent of amplitude. (WRM)

  15. Two Galileo Views of Thebe

    Science.gov (United States)

    1997-01-01

    These two images of the Jovian moon Thebe were taken by Galileo's solid state imaging system in November 1996 and June 1997, respectively. North is approximately up in both cases. Thebe, whose longest dimension is approximately 116 kilometers (72 miles) across, is tidally locked so that the same side of the satellite always points towards Jupiter, similar to how the nearside of our own Moon always points toward Earth. In such a tidally locked state, one side of Thebe always points in the direction in which Thebe moves as it orbits about Jupiter. This is called the 'leading side' of the moon and is shown at the left. The image on the right emphasizes the side of Thebe that faces away from Jupiter (the 'anti-Jupiter' side). Note that there appear to be at least three or four very large impact craters on the satellite--very large in the sense that each of these craters is roughly comparable in size to the radius of Thebe.The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  16. BDS/GPS/GLONASS/GALILEO 组合卫星导航系统仿真分析%Simulation and Analysis of BDS/GPS/GLONASS/GALILEO Integrated Satellite Navigation System

    Institute of Scientific and Technical Information of China (English)

    潜成胜; 马大喜

    2013-01-01

    全球卫星定位系统因其高精度、全天候等优点而被广泛应用,但是单一导航系统容易受环境及人为干扰,导致在区域精度和连续性上有较大问题。本文对组合导航系统进行仿真,组合中国BDS、美国GPS、俄罗斯GLONASS和欧盟的GALILEO四个全球卫星导航系统,利用仿真数据对目前GPS单一系统、当前不完整组合系统、未来完整组合系统在赣州地区的几何精度衰减因子( GDOP)值、可见卫星数及导航精度进行对比分析。通过仿真结果可以发现,与单一的GPS系统相比,组合系统在可见卫星数、GDOP和导航精度上都有非常大的优势。%The Global satellite Positioning System is applied widely because of its advantages of high accuracy and all-weather operation .However ,a single satellite positioning system is more susceptible to environmental and human dis-turbance ,which causes significant problems about precision and continuity in region .In this paper ,an integrated naviga-tion system which includes the Chinese BDS ,the U.S.GPS,the Russian GLONASS and the EU’s GALILEO was applied to be simulated .And the simulated data was used to compare the current single GPS system ,the current incomplete inte-grated system and the future complete integrated system ’ s GDOP,the number of visible satellites and navigation accuracy in Ganzhou area .The simulation results reveal that the integrated navigation system is more advantage than the single GPS system in GDOP ,the number of visible satellites and navigation accuracy .

  17. Mysteries Of The Farside Of The Moon: What Galileo Couldn't See

    Science.gov (United States)

    Pieters, Carlé M.

    When Galileo first turned his improved spyglass to view the Moon from Padua, he was astounded at what he saw: ``And it is like the face of the Earth itself … which is marked here and there with chains of mountains and depths of valleys'' (Galilei, 1610). His remarks about his new discoveries captured the joy which ultimately drives every planetary explorer: ``I render infinite thanks to God for being so kind as to make me alone the first observer of marvels kept hidden in obscurity for all previous centuries'' (Galilei, 1610). Four centuries later his intellectual heirs have expanded human understanding of our place in the universe with an elegant symmetry. The Apollo and Luna programs demonstrated that the origin and history of the Earth and the Moon are intimately linked. Two decades later the Galileo spacecraft swung by the Moon to obtain a gravity-assist from Earth in order to complete its exploration journey to Jupiter and the Galilean satellites. The Galileo spacecraft was the first to return to the Moon with modern sensors, and its brief passage provided dramatic evidence that the farside of the Moon held secrets unimagined from study of the nearside. Subsequent missions, Clementine and Lunar Prospector, provided the first global assessment of lunar topography and composition, and placed the farside in context. There are few of the extensive plains of basaltic lava on the farside of the Moon. This fact is clearly a product of the earliest history of the Moon (the first 500 My), the details of which are being investigated from clues that remain on the Moon today. The dominant feature on the lunar farside is the enormous South Pole-Aitken Basin, which extends from the south pole to the crater Aitken, just 15° south of the equator. This basin includes the deepest area on the Moon and appears as a slightly darker circular region encompassing the lower half of the lunar farside. The composition of the interior is uniquely enriched with iron-bearing minerals

  18. Galileo as viewed through scientometric looking glass

    Directory of Open Access Journals (Sweden)

    Bidyarthi Dutta

    2015-01-01

    Full Text Available The scientometric study of individual scientists was started in around early 80's of last century that required in-depth data on the concerned person only. Such kinds of studies involved contemporary scientists only. No such attempt for any classical scholar or scientist has ever been noticed. This paper attempts to develop the scientometric portrait of Galileo Galilei, Father of Modern Science. The study of impact of classic scientists like Copernicus, Galileo, Newton et al., through scientometric methodology bears significant implication in the context of history of science, genesis and evolution of scientific thought, sociology of science, etc., The inception of modern science was laid down with the wave of Copernican revolution in Europe in 15th century, with the publication of the book De revolutionibus orbium coelestium in 1543 by Nicholus Copernicus that challenged Aristotelian model. Later Galileo's telescopic observations and other experimental results added new dimensions to this revolutionary movement. Several new scientific thought contributions to this revolution were continued till Isaac Newton's work over more than a century later. This study has been executed by studying citations of Galileo's 11 publications (books, pamphlets and manuscripts from Web of Science over a time span of 58 years, that is, since 1955–2013. It has been observed that these 11 publications received 338 citations over the said time span from 227 source items including articles, conference papers, review, editorial material, etc. The subject areas of the source items have been studied through keyword analysis and it has been found that Galileo received citations from a wide range of subjects. The co-cited authors, cited documents, and citation ages are also studied. The substantive numbers of classic scientists such as Einstein, Newton, and Poincare have been found as co-cited authors of Galileo.

  19. 基于“伽利略”卫星的嵌入式导航系统设计%Design the embedded navigation system based on GALILEO satellite

    Institute of Scientific and Technical Information of China (English)

    莫绍强

    2015-01-01

    在现有海上船舶卫星导航系统中,GPS,GALILEO及北斗卫星相互补充,已形成成熟的导航应用。本文重点研究GALILEO卫星信号在其导航应用中的捕获及处理技术,针对GALILEO采取新的信号调制方式,传统信号接收及调解技术已经不能满足导航系统的性能要求,提出一种新的BPSK双通道信号捕获及调解技术,同时设计基于新方法的嵌入式导航系统。通过对GALILEO E1实时信号的测试,表明此算法的有效性。%In the maritime ship satellite navigation system, now have GPS, GALILEO and Beidou three kinds of navigation satellite. This paper first studies GALILEO signal capture technology and signal modulation regulation technology. To obtain a better performance of acquisition, the paper proposed a new method using BPSK-like technology and joint data/pilot acquisition strategies for acquisition of GALILEO E1 OS signals after the analysis of the foregoing problems.

  20. Galileo's Lute and the Law of Falling Bodies

    Science.gov (United States)

    Thompson, Mark

    2008-05-01

    Galileo's Lute and the Law of Falling Bodies is an excerpt from Galileo 1610. Galileo 1610 is a dramatic, musical and intellectual odyssey back to the life and times of Galileo Galilei, the famous 17th century Italian scientist and philosopher. It commemorates the 400th anniversary of Galileo's discoveries with his telescope in 1610. Dressed in authentic Renaissance attire as Galileo, the author-- a cantorial soloist and amateur astronomer-- tells the fascinating story of "The Father of Modern Science,” drawing from the actual correspondence and writings of Galileo, as well as those of his many biographers. Through his dialogue with the audience on a wide range of discoveries and opinions, "Galileo” shares his wisdom and his life experiences with pathos, wit and humor, lacing his narration with entertaining lute songs from the late Renaissance period, some of which were actually composed by Galileo's father, Vincenzo. Bridging the past to the present, the author breathes life into "Galileo” as he once again frolics and struggles among us. In bringing forth some of life's great issues, we learn something about our own inquisitive nature, as well as that of science and music. The author has appeared as Galileo for over a decade on radio, at community theatres and libraries, public schools, colleges and universities throughout the country. He has performed for civic organizations, astronomy association conventions, marketing and outreach programs as well as private events and parties. Galileo 1610 is suitable for a variety of educational and entertainment programs, for both children and adults. All presentations are tailored to fit the interest, experience and size of the audience.

  1. Dismantling of the research reactor RTS-1 Galileo Galilei in Pisa (Italy); Desmantelamiento del reactor de investigacion RTS-1 Galileo Galilei en Pisa (Italia)

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Martinez, J. t.; Farella, G.; Cimini, E.; Russo, M.

    2014-07-01

    This paper is about the most relevant aspects of the first phase of the dismantling, removal of the water in the pool, prior treatment through evaporation, the dismantling of all the submerged activated elements and other activated or contaminated elements that have been part of the nuclear facility. (Author)

  2. Galileo's Lens

    Science.gov (United States)

    Manos, Harry

    2003-05-01

    Most visitors to Florence, Italy, know about the Galleria dell'Accademia, housing Michelangelo's famous statue of David, or the Galleria degli Uffizi with the famous Medici collection. Few visitors know that only two blocks from the Uffizi on the Arno River is one of the world's finest museums featuring historic scientific instruments, the Museo di Storia della Scienza. In the February issue of TPT, Nickell states that the Museo di Storia della Scienza ``is perhaps the best museum on the history of science in the world.''1 This fact is likely true, and the museum is a must for physics teachers visiting Florence. It features a vast collection of authentic ``cutting-edge'' scientific instruments, including one of Galileo's lenses in a magnificent ebony and ivory frame. One of the tragedies is that this museum goes unmarked on many tourist maps and unmentioned in many guidebooks.

  3. N=2 supersymmetric extension of l-conformal Galilei algebra

    Energy Technology Data Exchange (ETDEWEB)

    Masterov, Ivan [Laboratory of Mathematical Physics, Tomsk Polytechnic University, 634050 Tomsk, Lenin Ave. 30 (Russian Federation)

    2012-07-15

    N=2 supersymmetric extension of the l-conformal Galilei algebra is constructed. A relation between its representations in flat spacetime and in Newton-Hooke spacetime is discussed. An infinite-dimensional generalization of the superalgebra is given.

  4. How Marius Was Right and Galileo Was Wrong Even Though Galileo Was Right and Marius Was Wrong

    CERN Document Server

    Graney, Christopher M

    2009-01-01

    Astronomers in the early 17th century misunderstood the images of stars that they saw in their telescopes. For this reason, the data a skilled observer of that time acquired via telescopic observation of the heavens appeared to support a geocentric Tychonic (or semi-Tychonic) world system, and not a heliocentric Copernican world system. Galileo Galilei made steps in the direction of letting observations lead him towards a Tychonic or semi-Tychonic world system. However, he ultimately backed the Copernican system, against the data he had on hand. By contrast, the German astronomer Simon Marius understood that data acquired by telescopic observation supported a Tychonic world system.

  5. The Galileo Affair.

    Science.gov (United States)

    Poole, Michael

    1990-01-01

    Presented is background material on Galileo and his views on astronomy, religion, and Copernicus. The history of theory development related to the science of astronomy and a review of Galileo's writings are included. (KR)

  6. BOOK REVIEW: Galileo's Muse: Renaissance Mathematics and the Arts

    Science.gov (United States)

    Peterson, Mark; Sterken, Christiaan

    2013-12-01

    Galileo's Muse is a book that focuses on the life and thought of Galileo Galilei. The Prologue consists of a first chapter on Galileo the humanist and deals with Galileo's influence on his student Vincenzo Viviani (who wrote a biography of Galileo). This introductory chapter is followed by a very nice chapter that describes the classical legacy: Pythagoreanism and Platonism, Euclid and Archimedes, and Plutarch and Ptolemy. The author explicates the distinction between Greek and Roman contributions to the classical legacy, an explanation that is crucial for understanding Galileo and Renaissance mathematics. The following eleven chapters of this book arranged in a kind of quadrivium, viz., Poetry, Painting, Music, Architecture present arguments to support the author's thesis that the driver for Galileo's genius was not Renaissance science as is generally accepted but Renaissance arts brought forth by poets, painters, musicians, and architects. These four sets of chapters describe the underlying mathematics in poetry, visual arts, music and architecture. Likewise, Peterson stresses the impact of the philosophical overtones present in geometry, but absent in algebra and its equations. Basically, the author writes about Galileo, while trying to ignore the Copernican controversy, which he sees as distracting attention from Galileo's scientific legacy. As such, his story deviates from the standard myth on Galileo. But the book also looks at other eminent characters, such as Galileo's father Vincenzo (who cultivated music and music theory), the painter Piero della Francesca (who featured elaborate perspectives in his work), Dante Alighieri (author of the Divina Commedia), Filippo Brunelleschi (who engineered the dome of the Basilica di Santa Maria del Fiore in Florence, Johannes Kepler (a strong supporter of Galileo's Copernicanism), etc. This book is very well documented: it offers, for each chapter, a wide selection of excellent biographical notes, and includes a fine

  7. Simulation Facilities and Test Beds for Galileo

    Science.gov (United States)

    Schlarmann, Bernhard Kl.; Leonard, Arian

    2002-01-01

    Galileo is the European satellite navigation system, financed by the European Space Agency (ESA) and the European Commission (EC). The Galileo System, currently under definition phase, will offer seamless global coverage, providing state-of-the-art positioning and timing services. Galileo services will include a standard service targeted at mass market users, an augmented integrity service, providing integrity warnings when fault occur and Public Regulated Services (ensuring a continuity of service for the public users). Other services are under consideration (SAR and integrated communications). Galileo will be interoperable with GPS, and will be complemented by local elements that will enhance the services for specific local users. In the frame of the Galileo definition phase, several system design and simulation facilities and test beds have been defined and developed for the coming phases of the project, respectively they are currently under development. These are mainly the following tools: Galileo Mission Analysis Simulator to design the Space Segment, especially to support constellation design, deployment and replacement. Galileo Service Volume Simulator to analyse the global performance requirements based on a coverage analysis for different service levels and degrades modes. Galileo System Simulation Facility is a sophisticated end-to-end simulation tool to assess the navigation performances for a complete variety of users under different operating conditions and different modes. Galileo Signal Validation Facility to evaluate signal and message structures for Galileo. Galileo System Test Bed (Version 1) to assess and refine the Orbit Determination &Time Synchronisation and Integrity algorithms, through experiments relying on GPS space infrastructure. This paper presents an overview on the so called "G-Facilities" and describes the use of the different system design tools during the project life cycle in order to design the system with respect to

  8. Galileo positioning technology

    CERN Document Server

    Lohan, Elena; Sand, Stephan; Hurskainen, Heikki

    2015-01-01

    This book covers multi-band Galileo receivers (especially E1-E5 bands of Galileo) and addresses all receiver building blocks, from the antenna and front end, through details of the baseband receiver processing blocks, up to the navigation processing, including the Galileo message structure and Position, Velocity, Time (PVT) computation. Moreover, hybridization solutions with communications systems for improved localization are discussed and an open-source GNSS receiver platform (available for download) developed at Tampere University of Technology (TUT) is addressed in detail. • Takes a holistic approach to GALILEO and related systems, such as EGNOS and hybrid solutions on mobile phones; • Provides an invaluable reference to Binary Offset Carrier modulations and related families, which are some of the trademarks of GALILEO; • Includes a detailed survey of GALILEO receiver research in Europe and existing software-defined radio (SDR) GALILEO receiver implementations; • Addresses the multiple challen...

  9. Modern Exploration of Galileo's New Worlds

    Science.gov (United States)

    Johnson, Torrence V.

    2010-01-01

    Four hundred years ago Galileo turned his telescope to the heavens and changed the way we view the cosmos forever. Among his discoveries in January of 1610 were four new 'stars', following Jupiter in the sky but changing their positions with respect to the giant planet every night. Galileo showed that these 'Medicean stars', as he named them, were moons orbiting Jupiter in the same manner that the Earth and planets revolve about the Sun in the Copernican theory of the solar system. Over the next three centuries these moons, now collectively named the Galilean satellites after their discoverer, remained tiny dots of light in astronomers' telescopes. In the latter portion of the twentieth century Galileo's new worlds became important targets of exploration by robotic spacecraft. This paper reviews the history of this exploration through the discoveries made by the Galileo mission from 1995 to 2003, setting the stage for on-going exploration in the new century.

  10. Impact of Galileo on Global Ionosphere Map Estimation

    NARCIS (Netherlands)

    Anh Quan Le

    2006-01-01

    The upcoming GNSS Galileo, with its new satellite geometry and frequency plan, will not only bring many benefits for navigation and positioning but also help to improve ionosphere delay estimation. This paper investigates ionosphere estimation with Galileo and compares it with the results from GPS-o

  11. Impact of Galileo on Global Ionosphere Map Estimation

    NARCIS (Netherlands)

    Anh Quan Le

    2006-01-01

    The upcoming GNSS Galileo, with its new satellite geometry and frequency plan, will not only bring many benefits for navigation and positioning but also help to improve ionosphere delay estimation. This paper investigates ionosphere estimation with Galileo and compares it with the results from

  12. Estimation and analysis of Galileo differential code biases

    Science.gov (United States)

    Li, Min; Yuan, Yunbin; Wang, Ningbo; Li, Zishen; Li, Ying; Huo, Xingliang

    2017-03-01

    When sensing the Earth's ionosphere using dual-frequency pseudorange observations of global navigation satellite systems (GNSS), the satellite and receiver differential code biases (DCBs) account for one of the main sources of error. For the Galileo system, limited knowledge is available about the determination and characteristic analysis of the satellite and receiver DCBs. To better understand the characteristics of satellite and receiver DCBs of Galileo, the IGGDCB (IGG, Institute of Geodesy and Geophysics, Wuhan, China) method is extended to estimate the satellite and receiver DCBs of Galileo, with the combined use of GPS and Galileo observations. The experimental data were collected from the Multi-GNSS Experiment network, covering the period of 2013-2015. The stability of both Galileo satellite and receiver DCBs over a time period of 36 months was thereby analyzed for the current state of the Galileo system. Good agreement of Galileo satellite DCBs is found between the IGGDCB-based DCB estimates and those from the German Aerospace Center (DLR), at the level of 0.22 ns. Moreover, high-level stability of the Galileo satellite DCB estimates is obtained over the selected time span (less than 0.25 ns in terms of standard deviation) by both IGGDCB and DLR algorithms. The Galileo receiver DCB estimates are also relatively stable for the case in which the receiver hardware device stays unchanged. It can also be concluded that the receiver DCB estimates are rather sensitive to the change of the firmware version and that the receiver antenna type has no great impact on receiver DCBs.

  13. Hubble Gallery of Jupiter's Galilean Satellites

    Science.gov (United States)

    1995-01-01

    This is a Hubble Space Telescope 'family portrait' of the four largest moons of Jupiter, first observed by the Italian scientist Galileo Galilei nearly four centuries ago. Located approximately one-half billion miles away, the moons are so small that, in visible light, they appear as fuzzy disks in the largest ground-based telescopes. Hubble can resolve surface details seen previously only by the Voyager spacecraft in the early 1980s. While the Voyagers provided close-up snapshots of the satellites, Hubble can now follow changes on the moons and reveal other characteristics at ultraviolet and near-infrared wavelengths.Over the past year Hubble has charted new volcanic activity on Io's active surface, found a faint oxygen atmosphere on the moon Europa, and identified ozone on the surface of Ganymede. Hubble ultraviolet observations of Callisto show the presence of fresh ice on the surface that may indicate impacts from micrometeorites and charged particles from Jupiter's magnetosphere.Hubble observations will play a complementary role when the Galileo spacecraft arrives at Jupiter in December of this year.This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu/pubinfo/

  14. [Galileo and his telescope].

    Science.gov (United States)

    Strebel, Christoph

    2006-01-01

    Galileo's publication of observations made with his newly reinvented telescope provoked a fierce debate. In April 1610 Martinus Horky, a young Bohemian astronomer, had an opportunity to make his own observations with Galileo's telescope in the presence of Antonio Magini and other astronomers. Horky and the other witnesses denied the adequacy of Galileo's telescope and therefore the bona fides of his discoveries. Kepler conjectured Horky as well as all his witnesses to be myopic. But Kepler's objection could not stop the publication of Horky's Peregrinatio contra nuncium sidereum (Modena, 1610), the first printed refutation of Galileo's Sidereus nuncius. In his treatise, Horky adresses four questions: 1) Do the four newly observed heavenly bodies actually exist? Horky denies their existence on various grounds: a) God, as every astronomer teaches, has created only seven moveable heavenly bodies and astronomical knowledge originates in God, too. b) Heavenly bodies are either stars or planets. Galileo's moveable heavenly bodies fit into neither category. c) If they do exist, why have they not already been observed by other scholars? Horky concludes that there are no such heavenly bodies. 2) What are these phenomena? They are purely artefactual, and produced by Galileo's telescope. 3) How are they like? Galileo's "stars" are so small as to be almost invisible. Galileo claims that he has measured their distances from each other. This however is impossible due to their diminutive size and other observational problems. Hence, Galileo's claim is a further proof that he is a fraud. 4) Why are they? For Galileo they are a chance to earn money but for astronomers like Horky they are a reason to offer thanks and honour to God. Horky's treatise was favourably received by the enemies of Galileo. But Kepler's critique was devastating. After calling on Kepler in Prague, Horky had to revoke the contents of his book.

  15. "Galileo Calling Earth..."

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    This guide presents an activity for helping students understand how data from the Galileo spacecraft is sent to scientists on earth. Students are asked to learn about the concepts of bit-rate and resolution and apply them to the interpretation of images from the Galileo Orbiter. (WRM)

  16. Intel Galileo essentials

    CERN Document Server

    Grimmett, Richard

    2015-01-01

    This book is for anyone who has ever been curious about using the Intel Galileo to create electronics projects. Some programming background is useful, but if you know how to use a personal computer, with the aid of the step-by-step instructions in this book, you can construct complex electronics projects that use the Intel Galileo.

  17. Positioning accuracy and reliability of GALILEO,integrated GPS-GALILEO system based on single positioning model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Chunmei; OU Jikun; YUAN Yunbin

    2005-01-01

    A kind of uniform reliability index suitable for the code and phase observations is presented and used in reliability evaluation of satellite systems. Then, based on 25 stations of Crustal Movement Observation Network of China, satellite visibility, positioning availability and observation reliability of GPS, GALILEO and integrated GPS- GALILEO are calculated and analyzed in detail. Simulation results reveal that the satellite visibility of GALILEO is superior to that of GPS. Given positioning accuracy, horizontal positioning availability of GALILEO is consistent with that of GPS, but its vertical positioning availability is superior to that of GPS. However, the integrated GPS-GALILEO is shown to be superior to each of the single systems in the aspects of positioning accuracy and availability. The reliability of code and phase observations based on GALILEO and integrated GPS-GALILEO system is superior to that of GPS both in spatial and temporal domains on the whole. The new reliability index presented is simple to calculate and reflects reliability differences of different satellite systems.

  18. Potential contribution of GALILEO to the TRF and the determination of ERPs

    Science.gov (United States)

    Weber, R.; Englich, S.:

    2006-10-01

    1. INTRODUCTION In addition to the existing GPS and GLONASS systems the EC and ESA plan to launch an European Satellite Navigation System (GALILEO) till end of 2009. 30 GALILEO satellites will populate three orbital planes with an inclination of about 56o. This paper strives to summarize potential improvements in geodetic point positioning and especially in the determination of Earth Rotation gained from the combined use of all three systems or at least of GPS+GALILEO.

  19. The Integrated GPS-Galileo Navigation Satellite System%未来的 GPS-Galileo组合导航卫星系统

    Institute of Scientific and Technical Information of China (English)

    邵炳军; 徐波

    2008-01-01

    @@ 目前人们普遍看好全球导航卫星系统(GNSS)在两个方面的发展,一是美国全球定位系统(GPS)导航卫星的升级更新和新导航信号的加入;二是以欧洲伽利略(Galileo)系统为主要代表的新全球卫星导航系统的发展.

  20. Dynamical realization of l-conformal Galilei algebra and oscillators

    Energy Technology Data Exchange (ETDEWEB)

    Galajinsky, Anton, E-mail: galajin@mph.phtd.tpu.ru [Laboratory of Mathematical Physics, Tomsk Polytechnic University, 634050 Tomsk, Lenin Ave. 30 (Russian Federation); Masterov, Ivan, E-mail: masterov@mph.phtd.tpu.ru [Laboratory of Mathematical Physics, Tomsk Polytechnic University, 634050 Tomsk, Lenin Ave. 30 (Russian Federation)

    2013-01-11

    The method of nonlinear realizations is applied to the l-conformal Galilei algebra to construct a dynamical system without higher derivative terms in the equations of motion. A configuration space of the model involves coordinates, which parametrize particles in d spatial dimensions, and a conformal mode, which gives rise to an effective external field. It is shown that trajectories of the system can be mapped into those of a set of decoupled oscillators in d dimensions.

  1. [Galileo and centrifugal force].

    Science.gov (United States)

    Vilain, Christiane

    This work intends to focus on Galileo's study of what is now called "centrifugal force," within the framework of the Second Day of his Dialogo written in 1632, rather than on the previously published commentaries on the topic. Galileo proposes three geometrical demonstrations in order to prove that gravity will always overcome centrifugalforce, and that the potential rotation of the Earth, whatever its speed, cannot in any case project objects beyond it. Each of these demonstrations must consequently contain an error and it has seemed to us that the first one had not been understood up until now. Our analysis offers an opportunity to return to Galileo's geometrical representation of dynamical questions; actually, we get an insight into the sophistication of Galileo's practices more than into his mistakes. Our second point, concerning the historiography of the problem, shows an evolution from anachronic critics to more contextual considerations, in the course of the second half of the twentieth century.

  2. Music in Galileo's Time

    Science.gov (United States)

    Petrobelli, P.

    2011-06-01

    Claudio Monteverdi appears as the key personality of the music in Galileo's time. His revolution in format and function of the musical language-from an essentially edonistic creation of purely sonorous images to a musical language consciously "expressive" of the content of the words on which it is based-is similar in character to the influential innovations in scientific thinking operated by Galileo.

  3. Galileo Ultraviolet Spectrometer experiment

    Science.gov (United States)

    Hord, C. W.; Mcclintock, W. E.; Stewart, A. I. F.; Barth, C. A.; Esposito, L. W.; Thomas, G. E.; Sandel, B. R.; Hunten, D. M.; Broadfoot, A. L.; Shemansky, D. E.

    1992-01-01

    The Galileo ultraviolet spectrometer experiment uses data obtained by the Ultraviolet Spectrometer (UVS) mounted on the pointed orbiter scan platform and from the Extreme Ultraviolet Spectrometer (EUVS) mounted on the spinning part of the orbiter with the field of view perpendicular to the spin axis. The UVS is a Ebert-Fastie design that covers the range 113-432 nm with a wavelength resolution of 0.7 nm below 190 and 1.3 nm at longer wavelengths. The UVS spatial resolution is 0.4 deg x 0.1 deg for illuminated disk observations and 1 deg x 0.1 deg for limb geometries. The EUVS is a Voyager design objective grating spectrometer, modified to cover the wavelength range from 54 to 128 nm with wavelength resolution 3.5 nm for extended sources and 1.5 nm for point sources and spatial resolution of 0.87 deg x 0.17 deg. The EUVS instrument will follow up on the many Voyager UVS discoveries, particularly the sulfur and oxygen ion emissions in the Io torus and molecular and atomic hydrogen auroral and airglow emissions from Jupiter. The UVS will obtain spectra of emission, absorption, and scattering features in the unexplored, by spacecraft, 170-432 nm wavelength region. The UVS and EUVS instruments will provide a powerful instrument complement to investigate volatile escape and surface composition of the Galilean satellites, the Io plasma torus, micro- and macro-properties of the Jupiter clouds, and the composition structure and evolution of the Jupiter upper atmosphere.

  4. Thermo-optical vacuum testing of Galileo In-Orbit Validation laser retroreflectors

    Science.gov (United States)

    Dell'Agnello, S.; Boni, A.; Cantone, C.; Ciocci, E.; Contessa, S.; Delle Monache, G.; Lops, C.; Martini, M.; Patrizi, G.; Porcelli, L.; Salvatori, L.; Tibuzzi, M.; Intaglietta, N.; Tuscano, P.; Mondaini, C.; Maiello, M.; Doyle, D.; García-Prieto, R.; Navarro-Reyes, D.

    2016-06-01

    The Galileo constellation is a space research and development program of the European Union to help navigate users all over the world. The Galileo IOV (In-Orbit Validation) are the first test satellites of the Galileo constellation and carry satellite laser retroreflectors as part of their payload systems for precision orbit determination and performance assessment. INFN-LNF SCF_Lab (Satellite/lunar/GNSS laser ranging/altimetry and Cube/microsat Characterization Facilities Laboratory) has been performing tests on a sample of the laser array segment under the Thermo-optical vacuum testing of Galileo IOV laser retro-reflectors of Galileo IOV LRA project, as defined in ESA-INFN Contract No. 4000108617/13/NL/PA. We will present the results of FFDP (Far Field Diffraction Pattern) and thermal relaxation times measurements in relevant space conditions of Galileo IOV CCRs (Cube Corner Retroreflectors) provided by ESA-ESTEC. A reference for the performance of laser ranging on Galileo satellites is the FFDP of a retroreflector in its design specifications and a Galileo retroreflector, in air and isothermal conditions, should have a minimum return intensity within the range [ 0.55 ×106m2- 2.14 ×106m2 ] (ESA-INFN, 2013). Measurements, performed in SCF_Lab facility, demonstrated that the 7 Galileo IOV laser retroreflectors under test were compliant with design performance expectations (Porcelli et al., 2015). The kind of tests carried out for this activity are the first performed on spare Galileo IOV hardware, made available after the launch of the four Galileo IOV satellites (2011 and 2012), which were the operational core of the constellation. The characterisation of the retroreflectors against their design requirements is important because LRAs (Laser Retroreflector Arrays) will be flown on all Galileo satellites.

  5. GALILEO系统在中国区域内的完好性分析%Integrity of the Galileo Satellite Navigation System on Different Condition in China Area

    Institute of Scientific and Technical Information of China (English)

    于亮; 万鑫; 李涌涛; 赵坷

    2013-01-01

    完善的完好性是伽利略卫星导航系统(Galileo)的重要特征之一,主要分析了Galileo系统在中国地区的完好性性能.简要介绍了Galileo系统,在此基础上利用仿真数据,分别从不同高度截止角、不同伪距误差和不同测站点等三个方面对Galileo系统在中国地区的完好性的影响进行了比较和分析,并得出有益的结论.

  6. Galileo Mission Science Briefing

    Science.gov (United States)

    1989-07-01

    The first of two tapes of the Galileo Mission Science press briefing is presented. The panel is moderated by George Diller from the Kennedy Space Center (KSC) Public Affairs Office. The participants are John Conway, the director of Payload and operations at Kennedy; Donald E. Williams, Commander of STS-43, the shuttle mission which will launch the Galileo mission; John Casani, the Deputy Assistant Director of Flight Projects at the Jet Propulsion Lab (JPL); Dick Spehalski, Galileo Project Manager at JPL; and Terrence Johnson, Galileo Project Scientist at JPL. The briefing begins with an announcement of the arrival of the Galileo Orbiter at KSC. The required steps prior to the launch are discussed. The mission trajectory and gravity assists from planetary and solar flybys are reviewed. Detailed designs of the orbiter are shown. The distance that Galileo will travel from the sun precludes the use of solar energy for heat. Therefore Radioisotope heater units are used to keep the equipment at operational temperature. A video of the arrival of the spacecraft at KSC and final tests and preparations is shown. Some of the many science goals of the mission are reviewed. Another video showing an overview of the Galileo mission is presented. During the question and answer period, the issue of the use of plutonium on the mission is broached, which engenders a review of the testing methods used to ensure the safety of the capsules containing the hazardous substance. This video has actual shots of the orbiter, as it is undergoing the final preparations and tests for the mission.

  7. Ambitious Galileo Project Starts in 2004

    Institute of Scientific and Technical Information of China (English)

    LiuJie

    2004-01-01

    Ministry of Science and Tech nology of the People's Repub lic of China released that the Galileo Project, the biggest cooperative program between China and Europe would implement fully in 2004. China will work with Europe in the fields of satellite navigation technology,manufacture, service and marketing,products standard and frequencies. It's expected to improve China's ability to develop its indigenous navigation and positioning system.

  8. Home automation with Intel Galileo

    CERN Document Server

    Dundar, Onur

    2015-01-01

    This book is for anyone who wants to learn Intel Galileo for home automation and cross-platform software development. No knowledge of programming with Intel Galileo is assumed, but knowledge of the C programming language is essential.

  9. The Cambridge companion to Galileo

    CERN Document Server

    1998-01-01

    This collection of essays is unparalleled in the depth of its coverage of all facets of Galileo's work. A particular feature of the volume is the treatment of Galileo's relationship with the Church. It will be of particular interest to philosophers, historians of science, cultural historians and those in religious studies. New readers and nonspecialists will find this the most convenient, accessible guide to Galileo available. Advanced students and specialists will find a conspectus of recent developments in the interpretation of Galileo.

  10. The Galileo Solid-State Imaging experiment

    Science.gov (United States)

    Belton, Michael J. S.; Klaasen, Kenneth P.; Clary, Maurice C.; Anderson, James L.; Anger, Clifford D.; Carr, Michael H.; Chapman, Clark R.; Davies, Merton E.; Greeley, Ronald; Anderson, Donald

    1992-01-01

    The Galileo Orbiter's Solid-State Imaging (SSI) experiment uses a 1.5-m focal length TV camera with 800 x 800 pixel, virtual-phase CCD detector in order to obtain images of Jupiter and its satellites which possess a combination of sensitivity levels, spatial resolutions, geometric fidelity, and spectral range that are unmatched by earlier imaging data. After describing the performance of this equipment on the basis of ground calibrations, attention is given to the SSI experiment's Jupiter system observation objectives; these encompass atmospheric science, satellite surfaces, ring structure, and 'darkside' experiments.

  11. Galileo Station Keeping Strategy

    Science.gov (United States)

    Perez-Cambriles, Antonio; Bejar-Romero, Juan Antonio; Aguilar-Taboada, Daniel; Perez-Lopez, Fernando; Navarro, Daniel

    2007-01-01

    This paper presents analyses done for the design and implementation of the Maneuver Planning software of the Galileo Flight Dynamics Facility. The station keeping requirements of the constellation have been analyzed in order to identify the key parameters to be taken into account in the design and implementation of the software.

  12. Galileo and prior philosophy

    NARCIS (Netherlands)

    Atkinson, D; Peijnenburg, J

    2004-01-01

    Galileo claimed inconsistency in the Aristotelian dogma concerning failing bodies and stated that all bodies must fall at the same rate. However, there is an empirical situation where the speeds of falling bodies are proportional to their weights; and even in vacuo all bodies do not fall at the same

  13. The Galileo Ground Segment Integrity Algorithms: Design and Performance

    Directory of Open Access Journals (Sweden)

    Carlos Hernández Medel

    2008-01-01

    Full Text Available Galileo, the European Global Navigation Satellite System, will provide to its users highly accurate global positioning services and their associated integrity information. The element in charge of the computation of integrity messages within the Galileo Ground Mission Segment is the integrity processing facility (IPF, which is developed by GMV Aerospace and Defence. The main objective of this paper is twofold: to present the integrity algorithms implemented in the IPF and to show the achieved performance with the IPF software prototype, including aspects such as: implementation of the Galileo overbounding concept, impact of safety requirements on the algorithm design including the threat models for the so-called feared events, and finally the achieved performance with real GPS and simulated Galileo scenarios.

  14. Galileo disposal strategy: stability, chaos and predictability

    Science.gov (United States)

    Rosengren, Aaron J.; Daquin, Jérôme; Tsiganis, Kleomenis; Alessi, Elisa Maria; Deleflie, Florent; Rossi, Alessandro; Valsecchi, Giovanni B.

    2017-02-01

    Recent studies have shown that the medium-Earth orbit (MEO) region of the global navigation satellite systems is permeated by a devious network of lunisolar secular resonances, which can interact to produce chaotic and diffusive motions. The precarious state of the four navigation constellations, perched on the threshold of instability, makes it understandable why all past efforts to define stable graveyard orbits, especially in the case of Galileo, were bound to fail; the region is far too complex to allow for an adoption of the simple geosynchronous disposal strategy. We retrace one such recent attempt, funded by ESA's General Studies Programme in the frame of the GreenOPS initiative, that uses a systematic parametric approach and the straightforward maximum-eccentricity method to identify long-term-stable regions, suitable for graveyards, as well as large-scale excursions in eccentricity, which can be used for post-mission deorbiting of constellation satellites. We then apply our new results on the stunningly rich dynamical structure of the MEO region towards the analysis of these disposal strategies for Galileo, and discuss the practical implications of resonances and chaos in this regime. We outline how the identification of the hyperbolic and elliptic fixed points of the resonances near Galileo can lead to explicit criteria for defining optimal disposal strategies.

  15. Calibration of Galileo signals for time metrology.

    Science.gov (United States)

    Defraigne, Pascale; Aerts, Wim; Cerretto, Giancarlo; Cantoni, Elena; Sleewaegen, Jean-Marie

    2014-12-01

    Using global navigation satellite system (GNSS) signals for accurate timing and time transfer requires the knowledge of all electric delays of the signals inside the receiving system. GNSS stations dedicated to timing or time transfer are classically calibrated only for Global Positioning System (GPS) signals. This paper proposes a procedure to determine the hardware delays of a GNSS receiving station for Galileo signals, once the delays of the GPS signals are known. This approach makes use of the broadcast satellite inter-signal biases, and is based on the ionospheric delay measured from dual-frequency combinations of GPS and Galileo signals. The uncertainty on the so-determined hardware delays is estimated to 3.7 ns for each isolated code in the L5 frequency band, and 4.2 ns for the ionosphere-free combination of E1 with a code of the L5 frequency band. For the calibration of a time transfer link between two stations, another approach can be used, based on the difference between the common-view time transfer results obtained with calibrated GPS data and with uncalibrated Galileo data. It is shown that the results obtained with this approach or with the ionospheric method are equivalent.

  16. Galileu Galilei dramaturgo: Argomento e traccia di una commedia

    Directory of Open Access Journals (Sweden)

    Roberta Barni

    2005-12-01

    Full Text Available Galileu Galilei, apaixonado apreciador de teatro, em aparente aplicação prévia daqueles preceitos mais tarde formulados em seu Dialogo dei Massimi Sistemi, escreveu um argumento teatral, uma comédia, inacabada, em duas diferentes versões. A segunda versão, mais completa, incorpora claramente os padrões da Commedia dell´Arte. Esses escritos estão hoje contidos no Volume IX de suas Opere, publicadas em Florença em 1933. Neste artigo notamos a peculiaridade da redação da comédia galileana e apresentamos sua versão, inédita, em português.

  17. Galileo as a Patient

    Science.gov (United States)

    Thiene, G.; Basso, C.

    2011-06-01

    The clinical history of Galileo, as it turns out from hundred letters he wrote and received, is so informative as to make it possible to delineate the natural history of his body. It is well known that he suffered from recurrent episodes of fever (terzana) since 1606, when he was in Florence as guest of Cristina Lorena for education of the future granduke Cosimo II. By reading signs and symptoms he reported several times, it is clear that he had various diseases (rheumatism, haemorroids, kidney stones, arrhythmias). When in December 1632, at the age of 68, Galileo delayed his journey to Rome claiming sickness, Pope Urban VIII committed 3 physicians to examine him. They reported that Galileo was affected by "pulsus intermittens" (most probably atrial fibrillation), large hernia at risk of rupture, dizziness, diffuse pain, hypochondriacal melancholy as a consequence of the "declining age". It was in February 1637 that he started to have eye disease with lacrimation and progressive loss of sight, which in 10 months led to loose at first the right eye and then also the left one. According to the consultation, asked at distance to Giovanni Trullio on February 1538 in Rome, the diagnosis of blindness due to bilateral uveitis came out. Keeping with the current medicine, the illnes might have been explained in the setting of an immune rheumatic disease (Reiter's syndrome). The cause of Galileo's death, which occurred on 8 January 1642 at the age of 78, is not known since it was not submitted to autopsy. We can speculate cardiac death due to pneumonia complicating congestive heart failure.

  18. GALILEO: la promessa che diventa realtà

    Directory of Open Access Journals (Sweden)

    Gianluca Pititto

    2013-08-01

    Full Text Available Presso il Centro Spaziale di Telespazio al Fucino (l’ Aquila il 24 Luglio scorso - alla presenza di alte autorità politiche, militari e civili - è stato fatto il punto sul progetto del GNSS civile europeo GALILEO ed è stata effettuata la prima dimostrazione pubblica ‘live’ delle capacità di fixing del sistema, che al momento conta solo su 4 dei 30 satelliti previsti per la costellazione completa. Il successo del test è stato superiore alle attese.On July 24 the European Commission has organized at the Fucino Space Center (Telespazio, L’Aquila – Italy a public demonstration of the current capability of the Civil European GNSS Galileo for accurate determination of geographical position (fix. Galileo is currently in the process of deployment in the space around the Earth and only 4 satellite of the final constellation (30 satellites are actually orbiting in space. With only these few satellites was possible to make a misurament affected by only 2 mt of error, a result beyond the most optimistic expectations with only 4 satellites operating. The event took place at the presence of high Italian and European authorities, civil and military, and even of a largepress representation. Galileo will be fully operational in 2020.

  19. A Modern Visit to Galileo

    Science.gov (United States)

    Freilich, Florence G.

    1970-01-01

    Describes the author's visit to the Italian cities where Galileo lived. Discusses the legendary swinging Cathedral lamp and the Leaning Tower of Pisa. Describes the science apparatus used by Galileo and other men of science which appear in the Museum of the History of Science in Florence. Presents six pictures of items viewed within the museum.…

  20. Performance Analysis of Several GPS/Galileo Precise Point Positioning Models

    Directory of Open Access Journals (Sweden)

    Akram Afifi

    2015-06-01

    Full Text Available This paper examines the performance of several precise point positioning (PPP models, which combine dual-frequency GPS/Galileo observations in the un-differenced and between-satellite single-difference (BSSD modes. These include the traditional un-differenced model, the decoupled clock model, the semi-decoupled clock model, and the between-satellite single-difference model. We take advantage of the IGS-MGEX network products to correct for the satellite differential code biases and the orbital and satellite clock errors. Natural Resources Canada’s GPSPace PPP software is modified to handle the various GPS/Galileo PPP models. A total of six data sets of GPS and Galileo observations at six IGS stations are processed to examine the performance of the various PPP models. It is shown that the traditional un-differenced GPS/Galileo PPP model, the GPS decoupled clock model, and the semi-decoupled clock GPS/Galileo PPP model improve the convergence time by about 25% in comparison with the un-differenced GPS-only model. In addition, the semi-decoupled GPS/Galileo PPP model improves the solution precision by about 25% compared to the traditional un-differenced GPS/Galileo PPP model. Moreover, the BSSD GPS/Galileo PPP model improves the solution convergence time by about 50%, in comparison with the un-differenced GPS PPP model, regardless of the type of BSSD combination used. As well, the BSSD model improves the precision of the estimated parameters by about 50% and 25% when the loose and the tight combinations are used, respectively, in comparison with the un-differenced GPS-only model. Comparable results are obtained through the tight combination when either a GPS or a Galileo satellite is selected as a reference.

  1. Performance Analysis of Several GPS/Galileo Precise Point Positioning Models.

    Science.gov (United States)

    Afifi, Akram; El-Rabbany, Ahmed

    2015-06-19

    This paper examines the performance of several precise point positioning (PPP) models, which combine dual-frequency GPS/Galileo observations in the un-differenced and between-satellite single-difference (BSSD) modes. These include the traditional un-differenced model, the decoupled clock model, the semi-decoupled clock model, and the between-satellite single-difference model. We take advantage of the IGS-MGEX network products to correct for the satellite differential code biases and the orbital and satellite clock errors. Natural Resources Canada's GPSPace PPP software is modified to handle the various GPS/Galileo PPP models. A total of six data sets of GPS and Galileo observations at six IGS stations are processed to examine the performance of the various PPP models. It is shown that the traditional un-differenced GPS/Galileo PPP model, the GPS decoupled clock model, and the semi-decoupled clock GPS/Galileo PPP model improve the convergence time by about 25% in comparison with the un-differenced GPS-only model. In addition, the semi-decoupled GPS/Galileo PPP model improves the solution precision by about 25% compared to the traditional un-differenced GPS/Galileo PPP model. Moreover, the BSSD GPS/Galileo PPP model improves the solution convergence time by about 50%, in comparison with the un-differenced GPS PPP model, regardless of the type of BSSD combination used. As well, the BSSD model improves the precision of the estimated parameters by about 50% and 25% when the loose and the tight combinations are used, respectively, in comparison with the un-differenced GPS-only model. Comparable results are obtained through the tight combination when either a GPS or a Galileo satellite is selected as a reference.

  2. Lattice Monte Carlo simulation of Galilei variant anomalous diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Gang, E-mail: hndzgg@aliyun.com [School of Information System and Management, National University of Defense Technology, Changsha, 410073 (China); Institute of Computer Science, University of Rostock, Albert Einstein Str. 22, Rostock, 18059 (Germany); Bittig, Arne, E-mail: arne.bittig@uni-rostock.de [Institute of Computer Science, University of Rostock, Albert Einstein Str. 22, Rostock, 18059 (Germany); Uhrmacher, Adelinde, E-mail: lin@informatik.uni-rostock.de [Institute of Computer Science, University of Rostock, Albert Einstein Str. 22, Rostock, 18059 (Germany)

    2015-05-01

    The observation of an increasing number of anomalous diffusion phenomena motivates the study to reveal the actual reason for such stochastic processes. When it is difficult to get analytical solutions or necessary to track the trajectory of particles, lattice Monte Carlo (LMC) simulation has been shown to be particularly useful. To develop such an LMC simulation algorithm for the Galilei variant anomalous diffusion, we derive explicit solutions for the conditional and unconditional first passage time (FPT) distributions with double absorbing barriers. According to the theory of random walks on lattices and the FPT distributions, we propose an LMC simulation algorithm and prove that such LMC simulation can reproduce both the mean and the mean square displacement exactly in the long-time limit. However, the error introduced in the second moment of the displacement diverges according to a power law as the simulation time progresses. We give an explicit criterion for choosing a small enough lattice step to limit the error within the specified tolerance. We further validate the LMC simulation algorithm and confirm the theoretical error analysis through numerical simulations. The numerical results agree with our theoretical predictions very well.

  3. Lossless Compression and Rate Control for the Galileo NIMS Experiment

    Science.gov (United States)

    Rice, R.; Mehlman, R.

    1994-01-01

    The Galileo Near-Infrared Mapping Spectrometer (NIMS) is a sophisticated multi-spectral instrument that was developed to study the spatial/compositional aspects of the atmosphere of Jupiter and the surfaces of it's satellites. Since its original development, the communication capability of the Galileo spacecraft has been severly reduced as the result of a failure of ground controllers to open the main antenna. The data rate which will be available for all instruments at the first Jupiter encounter in 1995 has been reduced by several orders of magnitude (even after recent numerous improvements to data link efficiency.).

  4. Real-time Galileo Orbit and Clock Corrections Using IGS MGEX Resources

    Science.gov (United States)

    Weber, G.; Dach, R.; Mervart, L.; Prange, L.; Stöcker, D.; Söhne, W.

    2013-12-01

    In March 2013 the Galileo In Orbit Validation (IOV) satellites began transmitting broadcast ephemeris information which is an essential precondition for using them in real-time Precise Point Positioning (PPP). Since about the same time we also have RTCM standards for Galileo broadcast ephemeris (BE) messages and so-called Galileo Multiple Signal Messages (MSM). Moreover, a draft has recently been presented to RTCM for Galileo orbit and clock correction messages following the State Space Representation (SSR) approach. This eagerly awaited progress in RTCM standardization allows converting different proprietary stream formats to one common format for all GNSS observations. It significantly facilitates utilizing data from inhomogeneous reference networks such as the IGS Multi-GNSS Experiment (MGEX) wherein a variety of receiver brands participates. With MSM accompanied by BE and SSR messages, everything is available by now for real-time PPP which includes Galileo satellites and applies open RTCM standards. RINEX-3 files from a globally distributed set of MGEX reference stations were used to generate Galileo orbit predictions with the Bernese GNSS software. The RTNet software by GPS Solutions then estimated Galileo clock corrections in real-time based on MSM streams derived from MGEX. The BKG Ntrip Client (BNC) finally encoded Galileo SSR streams carrying predicted orbits and estimated clocks for global correction dissemination via Ntrip broadcasters. The presentation describes the required implementation of recent RTCM standards for Galileo, specifically with regard to Open Source tools. The usage of BNC for RTCM stream conversion and RINEX-3 file editing, concatenation and quality check is shown taking Galileo as an example. A Multi-GNSS PPP option in BNC allows monitoring the overall performance of the complete processing chain. Real-time PPP time series of displacements represent errors coming from orbit predictions as well as from current limitations in the

  5. Francesco Ingoli's essay to Galileo: Tycho Brahe and science in the Inquisition's condemnation of the Copernican theory

    CERN Document Server

    Graney, Christopher M

    2012-01-01

    In January of 1616, the month before before the Roman Inquisition would infamously condemn the Copernican theory as being "foolish and absurd in philosophy", Monsignor Francesco Ingoli addressed Galileo Galilei with an essay entitled "Disputation concerning the location and rest of Earth against the system of Copernicus". A rendition of this essay into English, along with the full text of the essay in the original Latin, is provided in this paper. The essay, upon which the Inquisition condemnation was likely based, lists mathematical, physical, and theological arguments against the Copernican theory. Ingoli asks Galileo to respond to those mathematical and physical arguments that are "more weighty", and does not ask him to respond to the theological arguments at all. The mathematical and physical arguments Ingoli presents are largely the anti-Copernican arguments of the great Danish astronomer Tycho Brahe; one of these (an argument based on measurements of the apparent sizes of stars) was all but unanswerable...

  6. Generalizing Galileo's passé-dix game

    Science.gov (United States)

    Hombas, Vassilios

    2012-07-01

    This article shows a generalization of Galileo's 'passé-dix' game. The game was born following one of Galileo's [G. Galileo, Sopra le Scoperte dei Dadi (Galileo, Opere, Firenze, Barbera, Vol. 8). Translated by E.H. Thorne, 1898, pp. 591-594] explanations on a paradox that occurred in the experiment of tossing three fair 'six-sided' dice.

  7. Generalizing Galileo's Passe-Dix Game

    Science.gov (United States)

    Hombas, Vassilios

    2012-01-01

    This article shows a generalization of Galileo's "passe-dix" game. The game was born following one of Galileo's [G. Galileo, "Sopra le Scoperte dei Dadi" (Galileo, Opere, Firenze, Barbera, Vol. 8). Translated by E.H. Thorne, 1898, pp. 591-594] explanations on a paradox that occurred in the experiment of tossing three fair "six-sided" dice.…

  8. Becoming Galileo in the Classroom

    Science.gov (United States)

    Cavicchi, Elizabeth

    2011-04-01

    Galileo's contributions are so familiar as to be taken for granted, obscuring the exploratory process by which his discoveries arose. The wonder that Galileo experienced comes alive for undergraduates and teachers that I teach, when they find themselves taking Galileo's role by means of their own explorations. These classroom journeys include: sighting through picture frames to understand perspective, watching the night sky, experimenting with lenses and motion, and responding to Galileo's story. In teaching, I use critical exploration, the research pedagogy developed by Eleanor Duckworth that arose historically from both the clinical interviewing of Jean Piaget and B"arbel Inhelder and the Elementary Science Study of the 1960s. During critical explorations, the teacher supports students' investigations by posing provocative experiences while interactively following students' emergent understandings. In the context of Galileo, students learned to observe carefully, trust their observations, notice things they had never noticed before, and extend their understanding in the midst of pervasive confusion. Personal investment moved students to question assumptions that they had never critically evaluated. By becoming Galileo in today's classroom, we found the ordinary world no less intriguing and unsettling to explore, as the historical world of protagonists in Galileo's Dialogue.

  9. Galileo a very short introduction

    CERN Document Server

    Drake, Stillman

    2001-01-01

    In a startling reinterpretation of the evidence, Stillman Drake advances the hypothesis that Galileo's trial and condemnation by the Inquisition was caused not by his defiance of the Church, but by the hostility of contemporary philosophers. Galileo's own beautifully lucid arguments are used to show how his scientific method was utterly divorced from the Aristotelian approach to physics in that it was based on a search not for causes but for laws. Galileo's method was of overwhelming significance for the development of modern physics, and led to a final parting of the ways between science and

  10. Working in the shadow of Galileo

    CERN Multimedia

    2005-01-01

    A new institute for theoretical particle physcis has opened on the outskirts of Florence. The Gallileo Galilei institute (GGI) will host small workshops, typically lasting two to three months, devoted to a specific subject area (1/2 page)

  11. What Does Galileo's Discovery of Jupiter's Moons Tell Us About the Process of Scientific Discovery?

    Science.gov (United States)

    Lawson, Anton E.

    In 1610, Galileo Galilei discovered Jupiter''smoons with the aid of a new morepowerful telescope of his invention. Analysisof his report reveals that his discoveryinvolved the use of at least three cycles ofhypothetico-deductive reasoning. Galileofirst used hypothetico-deductive reasoning to generateand reject a fixed star hypothesis.He then generated and rejected an ad hocastronomers-made-a-mistake hypothesis.Finally, he generated, tested, and accepted a moonhypothesis. Galileo''s reasoningis modeled in terms of Piaget''s equilibration theory,Grossberg''s theory of neurologicalactivity, a neural network model proposed by Levine &Prueitt, and another proposedby Kosslyn & Koenig. Given that hypothetico-deductivereasoning has played a rolein other important scientific discoveries, thequestion is asked whether it plays a rolein all important scientific discoveries. In otherwords, is hypothetico-deductive reasoningthe essence of the scientific method? Possiblealternative scientific methods, such asBaconian induction and combinatorial analysis,are explored and rejected as viablealternatives. Educational implications of thishypothetico-deductive view of scienceare discussed.

  12. Galileo's Trajectory with Mild Resistance

    Science.gov (United States)

    Groetsch, C. W.

    2012-01-01

    An aspect of Galileo's classical trajectory that persists in a simple resistance model is noted. The resistive model provides a case study for the classroom analysis of limiting behaviour of an implicitly defined function. (Contains 1 note.)

  13. Galileo - The Serial-Production AIT Challenge

    Science.gov (United States)

    Ragnit, Ulrike; Brunner, Otto

    2008-01-01

    The Galileo Project is one of the most demanding projects of ESA, being Europe's autarkic navigation system and a constellation composed of 30 satellites. This presentation points out the different phases of the project up to the full operational capability and the corresponding launch options with respect to launch vehicles as well as launch configurations. One of the biggest challenges is to set up a small serial 'production line' for the overall integration and test campaign of satellites. This production line demands an optimization of all relevant tasks, taking into account also backup and recovery actions. A comprehensive AIT concept is required, reflecting a tightly merged facility layout and work flow design. In addition a common data management system is needed to handle all spacecraft related documentation and to have a direct input-out flow for all activities, phases and positions at the same time. Process optimization is a well known field of engineering in all small high tech production lines, nevertheless serial production of satellites are still not the daily task in space business and therefore new concepts have to be put in place. Therefore, and in order to meet the satellites overall system optimization, a thorough interface between unit/subsystem manufacturing and satellite AIT must be realized to ensure a smooth flow and to avoid any process interruption, which would directly lead to a schedule impact.

  14. Galileo - The Serial-Production AIT Challenge

    Science.gov (United States)

    Ragnit, Ulrike; Brunner, Otto

    2008-01-01

    The Galileo Project is one of the most demanding projects of ESA, being Europe's autarkic navigation system and a constellation composed of 30 satellites. This presentation points out the different phases of the project up to the full operational capability and the corresponding launch options with respect to launch vehicles as well as launch configurations. One of the biggest challenges is to set up a small serial 'production line' for the overall integration and test campaign of satellites. This production line demands an optimization of all relevant tasks, taking into account also backup and recovery actions. A comprehensive AIT concept is required, reflecting a tightly merged facility layout and work flow design. In addition a common data management system is needed to handle all spacecraft related documentation and to have a direct input-out flow for all activities, phases and positions at the same time. Process optimization is a well known field of engineering in all small high tech production lines, nevertheless serial production of satellites are still not the daily task in space business and therefore new concepts have to be put in place. Therefore, and in order to meet the satellites overall system optimization, a thorough interface between unit/subsystem manufacturing and satellite AIT must be realized to ensure a smooth flow and to avoid any process interruption, which would directly lead to a schedule impact.

  15. On the potential of Galileo E5 for time transfer.

    Science.gov (United States)

    Martínez-Belda, Mari Carmen; Defraigne, Pascale; Bruyninx, Carine

    2013-01-01

    The main global navigation satellite systems (GNSS) technique currently used for accurate time and frequency transfer is based on an analysis of the ionosphere-free combinations of dual-frequency code and carrier phase measurements in a precise point positioning (PPP) mode. This technique analyses the observations of one GNSS station using external products for satellite clocks and orbits to determine the position and clock synchronization errors of this station. The frequency stability of this time transfer is limited by the noise and multipath of the Global Positioning System (GPS) and Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS) codes. In the near future, Galileo will offer a broadband signal E5, with low noise in the centimeter range and with the lowest multipath error ever observed. This paper investigates new analysis procedures based on the E5 codeplus- carrier (CPC) combination for time transfer. The CPC combination with E5 provides a noise level 10 times lower than the ionosphere-free combination of Galileo E1 and E5, which is very promising for improving GNSS time transfer performances. From some tests with simulated Galileo data, it is shown here that the use of the CPC combination with E5 does not improve, at present, the medium- and long-term stability of time transfer with respect to the ionosphere-free combination of Galileo E1 and E5 codes, because of the need for a second frequency signal to correct for the ionospheric delays and ambiguities.

  16. Minimal realization of ℓ-conformal Galilei algebra, Pais-Uhlenbeck oscillators and their deformation

    Energy Technology Data Exchange (ETDEWEB)

    Krivonos, Sergey [Bogoliubov Laboratory of Theoretical Physics, JINR,141980 Dubna (Russian Federation); Lechtenfeld, Olaf [Institut für Theoretische Physik and Riemann Center for Geometry and Physics,Leibniz Universität Hannover,Appelstrasse 2, D-30167 Hannover (Germany); Sorin, Alexander [Bogoliubov Laboratory of Theoretical Physics, JINR,141980 Dubna (Russian Federation); National Research Nuclear University MEPhI (Moscow Engineering Physics Institute),Kashirskoe Shosse 31, 115409 Moscow (Russian Federation); Dubna International University,141980, Dubna (Russian Federation)

    2016-10-17

    We present the minimal realization of the ℓ-conformal Galilei group in 2+1 dimensions on a single complex field. The simplest Lagrangians yield the complex Pais-Uhlenbeck oscillator equations. We introduce a minimal deformation of the ℓ=1/2 conformal Galilei (a.k.a. Schrödinger) algebra and construct the corresponding invariant actions. Based on a new realization of the d=1 conformal group, we find a massive extension of the near-horizon Kerr-dS/AdS metric.

  17. Minimal realization of $\\ell$-conformal Galilei algebra, Pais-Uhlenbeck oscillators and their deformation

    CERN Document Server

    Krivonos, Sergey; Sorin, Alexander

    2016-01-01

    We present the minimal realization of the $\\ell$-conformal Galilei group in 2+1 dimensions on a single complex field. The simplest Lagrangians yield the complex Pais-Uhlenbeck oscillator equations. We introduce a minimal deformation of the $\\ell$=1/2 conformal Galilei (a.k.a. Schr\\"odinger) algebra and construct the corresponding invariant actions. Based on a new realization of the d=1 conformal group, we find a massive extension of the near-horizon Kerr-dS/AdS metric.

  18. Galileo photometry of asteroid 243 Ida

    Science.gov (United States)

    Helfenstein, P.; Veverka, J.; Thomas, P.C.; Simonelli, D.P.; Klaasen, K.; Johnson, T.V.; Fanale, F.; Granahan, J.; McEwen, A.S.; Belton, M.; Chapman, C.

    1996-01-01

    Galileo imaging observations over phase angles 19.5?? to 109.8?? are combined with near-opposition Earth-based data to derive the photometric properties of Ida. To first order these properties are uniform over the surface and well modeled at ?? = 0.55 ??m by Hapke parameters ????0 = 0.22, h = 0.020, B0 = 1.5, g = -0.33, and ?? = 18?? with corresponding geometric albedo p = 0.21??0.030.01 and Bond albedo AB = 0.081??0.0170.008. Ida's photometric properties are more similar to those of "average S-asteroids" (P. Helfenstein and J. Veverka 1989, Asteroids II, Univ. of Arizona Press, Tucson) than are those of 951 Gaspra. Two primary color units are identified on Ida: Terrain A exhibits a spectrum with relatively shallower 1-??m absorption and a relatively steeper red spectral slope than average Ida, while Terrain B has a deeper 1-??m absorption and a less steep red slope. The average photometric properties of Ida and Terrain A are similar while those of Terrain B differ mostly in having a slightly higher value of ????0 (0.22 versus 0.21), suggesting that Terrain B consists of slightly brighter, more transparent regolith particles. Galileo observations of Ida's satellite Dactyl over phase angles 19.5?? to 47.6?? suggest photometric characteristics similar to those of Ida, the major difference being Dactyl's slightly lower albedo (0.20 compared to 0.21). ?? 1990 Academic Press, Inc.

  19. Galileo quale infrastruttura europea per la navigazione orientata ai servizi

    Directory of Open Access Journals (Sweden)

    Marco Lisi

    2014-05-01

    Full Text Available Galileo is a joint initiative of the European Union and the European Space Agency, and is currently the most ambitious service-oriented and technologically advanced that has everbeen developed in Europe.It's a navigation satellite system completely under civil control and has the purpose to distribute radio signals on a global scale for the localization, navigation, and time synchronization.Galileo is based on a constellation of 24 satellites, a worldwide network of ground stations and various control centers, dedicated to the control of the constellation, the management of the mission and the ongoing monitoring of performance.

  20. Galileo: ESA's greatest endeavor; the embodiment of Europe's choise to remain a world-power

    NARCIS (Netherlands)

    Beeftink, D.

    2011-01-01

    Galileo is a global satellite navigation system that is being built at the initiative of the European Space Agency (ESA) and the European Union (EU). It is going to be Europe's own independent satellite system, invulnerable to ill-willing foreign governments. This ambitious project is part of Europe

  1. Chinese Firms Participate in Galileo Project

    Institute of Scientific and Technical Information of China (English)

    LiuJie

    2005-01-01

    On the afternoon of March 9, 2005,the Nationa Remote Sensing Center ofChina (NRSCC), subsidiary of the Ministry of Science and Technology of China (MOST) signed an agreement on Galileo Project with China Galileo Industries Ltd.

  2. Coset spaces and Einstein manifolds with l-conformal Galilei symmetry

    Directory of Open Access Journals (Sweden)

    Dmitry Chernyavsky

    2016-10-01

    Full Text Available The group theoretic construction is applied to construct a novel dynamical realization of the l-conformal Galilei group in terms of geodesic equations on the coset space. A peculiar feature of the geodesics is that all their integrals of motion, including the accelerations, are functionally independent. The analysis in the recent work [Chernyavsky and Galajinsky (2016 [35

  3. Coset spaces and Einstein manifolds with l-conformal Galilei symmetry

    Science.gov (United States)

    Chernyavsky, Dmitry

    2016-10-01

    The group theoretic construction is applied to construct a novel dynamical realization of the l-conformal Galilei group in terms of geodesic equations on the coset space. A peculiar feature of the geodesics is that all their integrals of motion, including the accelerations, are functionally independent. The analysis in the recent work [Chernyavsky and Galajinsky (2016) [35

  4. Remark on higher-derivative mechanics with l-conformal Galilei symmetry

    CERN Document Server

    Masterov, Ivan

    2016-01-01

    Based on the results in [Nucl. Phys. B 866 (2013) 212], we consider a way to construct a higher-derivative mechanical model which possesses the l-conformal Galilei symmetry. The dynamical system describes deformed Pais-Uhlenbeck oscillator in the presence of an effective external field.

  5. Galileo and the Interpretation of the Bible.

    Science.gov (United States)

    Carroll, William E.

    1999-01-01

    Argues that, contrary to the common view, Galileo and the theologians of the Inquisition share the same fundamental principles of biblical interpretation. Contends that Galileo and these theologians thought that the Bible contained truths about nature, but Galileo denied what the theologians accepted as scientifically true. Contains 93 references.…

  6. German National Galileo Public Regulated Service (PRS) Testing Activities

    Science.gov (United States)

    Habrich, Heinz; Söhne, Wolfgang

    2013-04-01

    The European Global Navigation System (GNSS) Galileo is going to be established in the near future. Currently, four satellites are in place forming the In-Orbit-Testing (IOT) phase. Within the next years, the constellation will be filled. Full Operational Capability (FOC) will be reached 2019. Beside the Open Service (OS) which is comparable to other OS of existing GNSS, e.g., GPS C/A, there is a so-called Public Regulated Service (PRS) included in the IOT satellites already. The PRS will have improved robustness, i.e. robust signals which will be resistant against involuntary interferences, jamming and spoofing. The PRS signal is encrypted and there will be a restricted access to authorized users, e.g. safety and emergency services, authorities with security task, critical infrastructure organizations etc. The access to the PRS which will be controlled through a special key management will be managed and supervised within the European Union (EU) Member States (MS) by national authorities, the Competent PRS Authority (CPA). But a set of Common Minimum Standards (CMS) will define the minimum requirements applicable to each PRS participant. Nevertheless, each MS is responsible for its national key management. This presentation will inform about the testing activities for Galileo PRS in Germany. The coarse concept for the testing is explained, the schedule is outlined. Finally, the paper will formulate some expectations to the Galileo PRS, e.g. for international cooperation.

  7. Inter-system biases estimation in multi-GNSS relative positioning with GPS and Galileo

    Science.gov (United States)

    Deprez, Cecile; Warnant, Rene

    2016-04-01

    The recent increase in the number of Global Navigation Satellite Systems (GNSS) opens new perspectives in the field of high precision positioning. Particularly, the European Galileo program has experienced major progress in 2015 with the launch of 6 satellites belonging to the new Full Operational Capability (FOC) generation. Associated with the ongoing GPS modernization, many more frequencies and satellites are now available. Therefore, multi-GNSS relative positioning based on GPS and Galileo overlapping frequencies should entail better accuracy and reliability in position estimations. However, the differences between satellite systems induce inter-system biases (ISBs) inside the multi-GNSS equations of observation. Once these biases estimated and removed from the model, a solution involving a unique pivot satellite for the two considered constellations can be obtained. Such an approach implies that the addition of even one single Galileo satellite to the GPS-only model will strengthen it. The combined use of L1 and L5 from GPS with E1 and E5a from Galileo in zero baseline double differences (ZB DD) based on a unique pivot satellite is employed to resolve ISBs. This model removes all the satellite- and receiver-dependant error sources by differentiating and the zero baseline configuration allows atmospheric and multipath effects elimination. An analysis of the long-term stability of ISBs is conducted on various pairs of receivers over large time spans. The possible influence of temperature variations inside the receivers over ISB values is also investigated. Our study is based on the 5 multi-GNSS receivers (2 Septentrio PolaRx4, 1 Septentrio PolaRxS and 2 Trimble NetR9) installed on the roof of our building in Liege. The estimated ISBs are then used as corrections in the multi-GNSS observation model and the resulting accuracy of multi-GNSS positioning is compared to GPS and Galileo standalone solutions.

  8. Efectos relativistas en los sistemas Galileo, GPS y GLONASS

    CERN Document Server

    Pascual-Sánchez, J F

    2004-01-01

    Nowadays, the Global Navigation Satellite Systems (GNSS), working like global positioning systems, are the GPS (NAVSTAR) and the GLONASS, which only are operative when several relativistic effects are corrected. In the next years the Galileo system will be constructed, copying the GPS System if there is no an alternative project. In this work, it will be exposed that there is one alternative to the mere copy by means of the SYPOR project, using relativistic concepts, and without utilize the Newtonian ideas that are in the basic conception, so much of the GPS as of the GLONASS. According to the SYPOR project, the Galileo system would be exact, with no need of corrections, and it would have additional technological advantages.

  9. On dynamical realizations of l-conformal Galilei and Newton-Hooke algebras

    CERN Document Server

    Galajinsky, Anton

    2015-01-01

    In two recent papers [N. Aizawa, Y. Kimura, J. Segar, J. Phys. A 46 (2013) 405204] and [N. Aizawa, Z. Kuznetsova, F. Toppan, J. Math. Phys. 56 (2015) 031701], representation theory of the centrally extended l-conformal Galilei algebra has been applied so as to construct second order differential equations exhibiting the l-conformal Galilei group as kinematical symmetry. It was suggested to treat them as the Schrodinger equations which involve Hamiltonians describing dynamical systems without higher derivatives. The Hamiltonians possess two unusual features, however. First, they involve the standard kinetic term only for one degree of freedom, while the remaining variables provide contributions linear in momenta. This is typical for Ostrogradski's canonical approach to the description of higher derivative systems. Second, the Hamiltonian in the second paper is not Hermitian in the conventional sense. In this work, we study the classical limit of the quantum Hamiltonians and demonstrate that the first of them i...

  10. Precise orbit determination and point positioning using GPS, Glonass, Galileo and BeiDou

    Directory of Open Access Journals (Sweden)

    Tegedor J.

    2014-04-01

    Full Text Available State of the art Precise Point Positioning (PPP is currently based on dual-frequency processing of GPS and Glonass navigation systems. The International GNSS Service (IGS is routinely providing the most accurate orbit and clock products for these constellations, allowing point positioning at centimeter-level accuracy. At the same time, the GNSS landscape is evolving rapidly, with the deployment of new constellations, such as Galileo and BeiDou. The BeiDou constellation currently consists of 14 operational satellites, and the 4 Galileo In-Orbit Validation (IOV satellites are transmitting initial Galileo signals. This paper focuses on the integration of Galileo and BeiDou in PPP, together with GPS and Glonass. Satellite orbits and clocks for all constellations are generated using a network adjustment with observation data collected by the IGS Multi-GNSS Experiment (MGEX, as well as from Fugro proprietary reference station network. The orbit processing strategy is described, and orbit accuracy for Galileo and BeiDou is assessed via orbit overlaps, for different arc lengths. Kinematic post-processed multi-GNSS positioning results are presented. The benefits of multiconstellation PPP are discussed in terms of enhanced availability and positioning accuracy.

  11. Simon Marius vs. Galileo: Who First Saw Moons of Jupiter?

    Science.gov (United States)

    Pasachoff, Jay M.; Van Helden, Albert

    2016-10-01

    In his almanac for 1612 and book Mundus Iovalis of 1614, Simon Marius in Germany reported his discovery of moons around Jupiter, which he started writing down in late 1609 in the Julian calendar, which translated to 8 January 1610 in the Gregorian calendar in use by Galileo in Italy. Is Marius to be believed? Galileo certainly did not. But a Dutch jury of experts about three hundred years later reported that they validated the claim that Marius independently discovered the moons of Jupiter one day after Galileo first both saw and wrote down his discovery! There is no doubt that the names Io, Europa, Ganymede, and Callisto came from Marius (to whom they were suggested by Kepler). See JMP's Journal for the History of Astronomy article, 46(2), 218-234 (2015).Marius wrote that he had been observing the moons around Jupiter since November 1609 (Julian), using a neighboring nobleman's telescope, which would mean that he actually saw the Jupiter satellites first (though publish or perish). Whether this feat was technically possible comes down to discussions of the capabilities of telescopes in the early 17th century.The quadricentennial of Marius's book was celebrated in Nuremberg with a symposium that is now in press in German with an English translation expected. One of us (AVH) has recently prepared a complete English translation of Marius's book, superseding the partial translation made 100 years ago. There is no evidence that, whether he saw what we now call the Galilean satellites first or not, Marius appreciated their cosmological significance the way that Galileo soon did. And Marius was certainly the first to publish tables of the moons of Jupiter.We thank the Chapin Library of Williams College and the Huntington Library for assistance with first editions of Marius's 1614 book, and we thank Pierre Leich of the Simon Marius Gesellschaft for his consultations.

  12. Galileo disposal strategy: stability, chaos and predictability

    CERN Document Server

    Rosengren, Aaron J; Alessi, Elisa Maria; Deleflie, Florent; Rossi, Alessandro; Valsecchi, Giovanni B

    2015-01-01

    Recent studies have shown that the medium-Earth orbit (MEO) region of the Global Navigation Satellite Systems is permeated by a devious network of lunisolar secular resonances, which can interact to produce chaotic and diffusive motions. The precarious state of the four navigation constellations, perched on the threshold of instability, makes it understandable why all past efforts to define stable graveyard orbits, especially in the case of Galileo, were bound to fail; the region is far too complex to allow of an adoption of the simple geosynchronous disposal strategy. We retrace one such recent attempt, funded by ESA's General Studies Programme in the frame of the GreenOPS initiative, that uses a systematic parametric approach and the straightforward maximum-eccentricity method to identify long-term stable regions, suitable for graveyards, as well as large-scale excursions in eccentricity, which can be used for post-mission deorbiting of constellation satellites. We then apply our new results on the stunning...

  13. The Galileo Teacher Training Programme

    Science.gov (United States)

    Doran, Rosa

    The Galileo Teacher Training Program is a global effort to empower teachers all over the world to embark on a new trend in science teaching, using new technologies and real research meth-ods to teach curriculum content. The GTTP goal is to create a worldwide network of "Galileo Ambassadors", promoters of GTTP training session, and a legion of "Galileo Teachers", edu-cators engaged on the use of innovative resources and sharing experiences and supporting its pears worldwide. Through workshops, online training tools and resources, the products and techniques promoted by this program can be adapted to reach locations with few resources of their own, as well as network-connected areas that can take advantage of access to robotic, optical and radio telescopes, webcams, astronomy exercises, cross-disciplinary resources, image processing and digital universes (web and desktop planetariums). Promoters of GTTP are expert astronomy educators connected to Universities or EPO institutions that facilitate the consolidation of an active support to newcomers and act as a 24 hour helpdesk to teachers all over the world. GTTP will also engage in the creation of a repository of astronomy education resources and science research projects, ViRoS (Virtual Repository of resources and Science Projects), in order to simplify the task of educators willing to enrich classroom activities.

  14. Reflecting on Galileo's Inventing Telescope%伽利略发明望远镜之反思一二

    Institute of Scientific and Technical Information of China (English)

    关增建

    2008-01-01

    伽利略(Galileo Galilei,1564-1642)是意大利文艺复兴后期伟大的天文学家、力学家、哲学家、物理学家、数学家,也是近代实验物理学的开拓者,并被后人誉为“近代科学之父”。伽利略之所以能够成为科学史上的巨人,应该说他发明望远镜的过程发挥了恰到好处的作用。

  15. The Science and technology Behind Galileo - Europes GPS

    Science.gov (United States)

    Saaj, C.; Underwood, C. I.; Noakes, C.; Park, D. W. G.; Moore, T.

    Over recent years, the public has become increasingly aware of the existence of global satellite positioning systems, such as the American Global Positioning System (GPS), for which the generic term is Global Navigation Satellite System (GNSS). This is primarily due to high-profile use in various military conflicts, the acceptance of the technology by the leisure market (hill walking, yachting, etc) and the rapid development of mass-market applications (such as in-vehicle navigation). However, the public is still largely unaware of how GNSS is currently being utilized by researchers across a wide range of scientific applications. The aim of this paper is to provide answers to public's basic questions on GNSS and thereby raise public awareness on the science and technology behind the nascent Galileo project; a European initiative to design, build and deploy a global satellite positioning system similar to the GPS.

  16. In the Footsteps of Galileo

    Science.gov (United States)

    Erickson, John; van der Veen, W.; Moody, T.; O'Dea, T.

    2008-05-01

    This workshop links the goals of IYA to needs in science education. Lack of understanding of how science is practiced exists at all levels of society and is perpetuated by the way science is presented in classrooms and informal settings, often illustrated by the scientific method as a rigid multi-step process. This workshop presents an alternative to misleading scientific method lessons by highlighting some of Galileo's work. Looking through his telescope at four moons orbiting the planet Jupiter, Galileo gave priority to evidence over popular belief, completely changing the existing world view. We have adapted an activity developed by UC Berkeley's Lawrence Hall of Science in which students simulate observations of Jupiter's moons over several nights. The activity emphasizes the nature of science in regard to observations, evidence, predictions, models, hypotheses, and theories. A direct link is made between Galileo's work and the Five Essential Features of Inquiry as outlined in the National Science Education Standards. Participants will "observe” the Galilean moons of Jupiter, record data, make predictions, and analyze and model the data to determine orbital periods and distances for each moon. Extensions of this activity will be presented, including comparisons of the Jupiter system to the Earth-Moon system. Participants will also learn about Slooh, a robotic telescope that can be used by students to obtain their own images of Jupiter and its moons. As one way to have a multitude of learners in a variety of settings participate in IYA, this activity will be made available to many audiences for presentation in the fall of 2009. Participants in this workshop will discuss adaptations suitable for different groups and mechanisms for encouraging and enabling the presentation of this activity. Participants will receive a preliminary version of the adapted Jupiter activity and the BSCS publication: "Why Does Inquiry Matter?"

  17. Galileo's Problem with PRS or What's in a Phase?

    Directory of Open Access Journals (Sweden)

    M. Stephen Hodgart

    2011-01-01

    Full Text Available The upcoming Galileo global navigation satellite system has a design problem with the cosine-phased BOCc(15, 2.5 modulation of its Public Regulated Service (PRS A-code. This signal needs far more bandwidth than the available 40.92 MHz. The present signal and system specification cannot be expected to deliver design performance under practical operational conditions (noise, receiver phase distortion, and multipath. There would not have been this problem with sine-phased BOC(15, 2.5.

  18. Internet of Things with Intel Galileo

    CERN Document Server

    de Sousa, Miguel

    2015-01-01

    This book employs an incremental, step-by-step approach to get you familiarized with everything from the basic terms, board components, and development environments to developing real projects. Each project will demonstrate how to use specific board components and tools. Both Galileo and Galileo Gen 2 are covered in this book.

  19. Recreating Galileo's 1609 Discovery of Lunar Mountains

    Science.gov (United States)

    Pasachoff, Jay M.; Needham, Paul S.; Wright, Ernest T.; Gingerich, Owen

    2014-11-01

    The question of exactly which lunar features persuaded Galileo that there were mountains on the moon has not yet been definitively answered; Galileo was famously more interested in the concepts rather than the topographic mapping in his drawings and the eventual engravings. Since the pioneering work of Ewen Whitaker on trying to identify which specific lunar-terminator features were those that Galileo identified as mountains on the moon in his 1609 observations reported in his Sidereus Nuncius (Venice, 1610), and since the important work on the sequence of Galileo's observations by Owen Gingerich (see "The Mystery of the Missing 2" in Galilaeana IX, 2010, in which he concludes that "the Florentine bifolium sheet [with Galileo's watercolor images] is Galileo's source for the reworked lunar diagrams in Sidereus Nuncius"), there have been advances in lunar topographical measurements that should advance the discussion. In particular, one of us (E.T.W.) at the Scientific Visualization Studio of NASA's Goddard Space Flight Center has used laser-topography from NASA's Lunar Reconnaissance Orbiter to recreate what Galileo would have seen over a sequence of dates in late November and early December 1609, and provided animations both at native resolution and at the degraded resolution that Galileo would have observed with his telescope. The Japanese Kaguya spacecraft also provides modern laser-mapped topographical maps.

  20. The Galileo Legend as Scientific Folklore.

    Science.gov (United States)

    Lessl, Thomas M.

    1999-01-01

    Examines the various ways in which the legend of Galileo's persecution by the Roman Catholic Church diverges from scholarly readings of the Galileo affair. Finds five distinct themes of scientific ideology in the 40 accounts examined. Assesses the part that folklore plays in building and sustaining a professional ideology for the modern scientific…

  1. Classroom Explorations: Pendulums, Mirrors, and Galileo's Drama

    Science.gov (United States)

    Cavicchi, Elizabeth

    2011-01-01

    What do you see in a mirror when not looking at yourself? What goes on as a pendulum swings? Undergraduates in a science class supposed that these behaviors were obvious until their explorations exposed questions with no quick answers. While exploring materials, students researched Galileo, his trial, and its aftermath. Galileo came to life both…

  2. Galileo and the Rhetoric of Relativity.

    Science.gov (United States)

    Machamer, Peter

    1999-01-01

    Galileo fit in well with the neo-Protagorian, person-relative framework that was emerging around him in the late 16th and early 17th centuries in Western Europe. For Galileo, all knowledge depended crucially and essentially on first person experience, and at the same time this knowledge was objective, not subjective. Comments on the educational…

  3. The University System of Georgia's GALILEO.

    Science.gov (United States)

    Penson, Merryll

    1998-01-01

    The University System of Georgia and the Online Computer Library Center (OCLC) built the innovative electronic library GALILEO (GeorgiA LIbrary LEarning Online system). This article describes the cooperation, leadership, and technology that made GALILEO possible; the proposal; planning and implementation; governance; current status; and future…

  4. The Galileo Solid-State Imaging experiment

    Science.gov (United States)

    Belton, M.J.S.; Klaasen, K.P.; Clary, M.C.; Anderson, J.L.; Anger, C.D.; Carr, M.H.; Chapman, C.R.; Davies, M.E.; Greeley, R.; Anderson, D.; Bolef, L.K.; Townsend, T.E.; Greenberg, R.; Head, J. W.; Neukum, G.; Pilcher, C.B.; Veverka, J.; Gierasch, P.J.; Fanale, F.P.; Ingersoll, A.P.; Masursky, H.; Morrison, D.; Pollack, James B.

    1992-01-01

    The Solid State Imaging (SSI) experiment on the Galileo Orbiter spacecraft utilizes a high-resolution (1500 mm focal length) television camera with an 800 ?? 800 pixel virtual-phase, charge-coupled detector. It is designed to return images of Jupiter and its satellites that are characterized by a combination of sensitivity levels, spatial resolution, geometric fiedelity, and spectral range unmatched by imaging data obtained previously. The spectral range extends from approximately 375 to 1100 nm and only in the near ultra-violet region (??? 350 nm) is the spectral coverage reduced from previous missions. The camera is approximately 100 times more sensitive than those used in the Voyager mission, and, because of the nature of the satellite encounters, will produce images with approximately 100 times the ground resolution (i.e., ??? 50 m lp-1) on the Galilean satellites. We describe aspects of the detector including its sensitivity to energetic particle radiation and how the requirements for a large full-well capacity and long-term stability in operating voltages led to the choice of the virtual phase chip. The F/8.5 camera system can reach point sources of V(mag) ??? 11 with S/N ??? 10 and extended sources with surface brightness as low as 20 kR in its highest gain state and longest exposure mode. We describe the performance of the system as determined by ground calibration and the improvements that have been made to the telescope (same basic catadioptric design that was used in Mariner 10 and the Voyager high-resolution cameras) to reduce the scattered light reaching the detector. The images are linearly digitized 8-bits deep and, after flat-fielding, are cosmetically clean. Information 'preserving' and 'non-preserving' on-board data compression capabilities are outlined. A special "summation" mode, designed for use deep in the Jovian radiation belts, near Io, is also described. The detector is 'preflashed' before each exposure to ensure the photometric linearity

  5. Precise Point Positioning Model Using Triple GNSS Constellations: GPS, Galileo and BeiDou

    Science.gov (United States)

    Afifi, Akram; El-Rabbany, Ahmed

    2016-12-01

    This paper introduces a comparison between dual-frequency precise point positioning (PPP) post-processing model, which combines the observations of three different GNSS constellations, namely GPS, Galileo, and BeiDou and real-time PPP model. A drawback of a single GNSS system such as GPS, however, is the availability of sufficient number of visible satellites in urban areas. Combining GNSS observations offers more visible satellites to users, which in turn is expected to enhance the satellite geometry and the overall positioning solution. However, combining several GNSS observables introduces additional biases, which require rigorous modelling, including the GNSS time offsets and hardware delays. In this paper, a GNSS post-processing PPPP model is developed using ionosphere-free linear combination. The additional biases of the GPS, Galileo, and BeiDou combination are accounted for through the introduction of a new unknown parameter, which is identified as the inter-system bias, in the PPP mathematical model. Natural Resources Canada's GPSPace PPP software is modified to enable a combined GPS / Galileo / BeiDou PPP solution and to handle the newly inter-system bias. A total of four data sets at four IGS stations are processed to verify the developed PPP model. Precise satellite orbit and clock products from the IGS-MGEX network are used to correct of the GPS, Galileo and BeiDou measurements. For the real-time PPP model the corrections of the satellites orbit and clock are obtained through the international GNSS service (IGS) real-time service (RTS). GPS and Galileo Observations are used for the GNSS RTS-IGS PPP model as the RTS-IGS satellite products are not available for BeiDou satellites. This paper provides the GNSS RTS-IGS PPP model using different satellite clock corrections namely: IGS01, IGC01, IGS01, and IGS03. All PPP models results of convergence time and positioning precision are compared to the traditional GPS-only PPP model. It is shown that combining

  6. Single-frequency GNSS retrieval of vertical total electron content (VTEC) with GPS L1 and Galileo E5 measurements

    Science.gov (United States)

    Schüler, Torben; Abel Oladipo, Olushola

    2013-03-01

    The European Galileo satellite navigation system offers a signal in space that will enable us to deduce range measurements of unprecedented precision: the E5 broadband signal. These new code range measurements would be up to three or four times more accurate compared to nowadays GPS L1. However, E5 will be the only Galileo signal of that outstanding performance. For this reason, a single-frequency single-site ionospheric delay estimator is experimented with to retrieve absolute VTEC data. A single-frequency VTEC retrieval algorithm was developed and tested. It is following the principles published in Xia (1992), Issler et al. (2004), and Leick (1995, 2004). During the validation phase, we devoted considerable time to process GPS L1 measurements in order to assess the level of precision obtainable with current real-world GNSS measurements. We found the global average RMS to be close to 4 TECU (1.5-2.5 TECU at mid- and higher latitude stations) what is considered to be a promising result. The very limited Galileo satellite constellation present during the time of this study did not allow us to run the absolute VTEC retrieval algorithm with real Galileo data. However, we can demonstrate the significant improvements related to the Galileo E5 signal with the help of satellite-specific ionosphere retrieval results from the Galileo experimental satellite GIOVE-B, although only a limited set of data was available for that purpose. In addition, we are presenting a test case based on simulated data that also underlines that the precision figures will clearly improve when using Galileo E5 data. This could make single-frequency ionosphere retrieval more attractive in the future.

  7. Europa: Initial Galileo Geological Observations

    Science.gov (United States)

    Greeley, R.; Sullivan, R.; Klemaszewski, J.; Homan, K.; Head, J. W.; Pappalardo, R.T.; Veverka, J.; Clark, B.E.; Johnson, T.V.; Klaasen, K.P.; Belton, M.; Moore, J.; Asphaug, E.; Carr, M.H.; Neukum, G.; Denk, T.; Chapman, C.R.; Pilcher, C.B.; Geissler, P.E.; Greenberg, R.; Tufts, R.

    1998-01-01

    Images of Europa from the Galileo spacecraft show a surface with a complex history involving tectonic deformation, impact cratering, and possible emplacement of ice-rich materials and perhaps liquids on the surface. Differences in impact crater distributions suggest that some areas have been resurfaced more recently than others; Europa could experience current cryovolcanic and tectonic activity. Global-scale patterns of tectonic features suggest deformation resulting from non-synchronous rotation of Europa around Jupiter. Some regions of the lithosphere have been fractured, with icy plates separated and rotated into new positions. The dimensions of these plates suggest that the depth to liquid or mobile ice was only a few kilometers at the time of disruption. Some surfaces have also been upwarped, possibly by diapirs, cryomagmatic intrusions, or convective upwelling. In some places, this deformation has led to the development of chaotic terrain in which surface material has collapsed and/or been eroded. ?? 1998 Academic Press.

  8. El caso Galileo o las Paradojas de una Racionalidad Científica Positivista según Paul Karl Feyerabend

    Directory of Open Access Journals (Sweden)

    Teresa Gargiulo

    2014-12-01

    Full Text Available The Galilean case meant for Feyerabend the opportunity to prove methodological and historically the paradoxes and limitations of a positivist notion of science. Feyerabend demonstrates the contradictions that suppose the different attempts of neo-positivism logical to establish a demarcation criterion that defines what science is. He realizes how in the case of Galileo Galilei those elements against which the logical positivism tries to delimit a negative definition of science, paradoxically constitute the heart of the scientific endeavor. Now this does not mean –as a considerable number of critics have pointed out– that Feyerabend uphold an anarchic, irrational or relativist view about science. Conversely, in a positive sense it is possible to say that the emblematic case of Galileo not only offered to Feyerabend the occasion to formulate a negative and sceptical argumentation with regard to that notion of science but, at the same time, it represented for him a chance to rethink the science from a broader perspective or rationality.

  9. Return to Galileo? The Inquisition of the International Narcotic Control Board.

    Science.gov (United States)

    Small, Dan; Drucker, Ernest

    2008-05-07

    Nearly 400 years after Galileo Galilei of Florence was arraigned and convicted of suspected heresy by the ten member Congregation of the Holy Office (Inquisition), the International Narcotic Control Board (INCB) is similarly inserting itself into matters pertaining to innovations in healthcare and the public health response to addiction throughout the world. Like that earlier Inquisition of 1633 that convicted Galileo of heresy for holding that the sun is the centre of the universe with the earth revolving around it (in contradiction to church doctrine of the time) the INCB and its thirteen-member panel, now rails against any evidence out of sync with the established doctrine of the war on drugs--particularly those innovations in public health called harm reduction. The latest healthcare and harm reduction practices to attract the ire of the INCB Inquisition are elements of Canada's most effective and innovative measures to minimize the harms of drugs in Vancouver--supervised injection facilities and, recently, the potential establishment of supervised inhalation rooms--along with the long established practice of providing safer mouthpieces for pulmonary inhalation in British Columbia. This is particularly significant as it comes in the midst of a crucial battle between municipal and provincial authorities in BC with the federal government in Ottawa, which seems determined to undermine all the most effective HR programs that are the result of years of steady local and governmental support in Vancouver and now threatens to derail all these programs and spread doubt about their usefulness despite the overwhelmingly positive findings of serous research.

  10. Return to Galileo? The Inquisition of the International Narcotic Control Board

    Directory of Open Access Journals (Sweden)

    Small Dan

    2008-05-01

    Full Text Available Abstract Nearly 400 years after Galileo Galilei of Florence was arraigned and convicted of suspected heresy by the ten member Congregation of the Holy Office (Inquisition, the International Narcotic Control Board (INCB is similarly inserting itself into matters pertaining to innovations in healthcare and the public health response to addiction throughout the world. Like that earlier Inquisition of 1633 that convicted Galileo of heresy for holding that the sun is the centre of the universe with the earth revolving around it (in contradiction to church doctrine of the time the INCB and its thirteen-member panel, now rails against any evidence out of sync with the established doctrine of the war on drugs – particularly those innovations in public health called harm reduction. The latest healthcare and harm reduction practices to attract the ire of the INCB Inquisition are elements of Canada's most effective and innovative measures to minimize the harms of drugs in Vancouver – supervised injection facilities and, recently, the potential establishment of supervised inhalation rooms – along with the long established practice of providing safer mouthpieces for pulmonary inhalation in British Columbia. This is particularly significant as it comes in the midst of a crucial battle between municipal and provincial authorities in BC with the federal government in Ottawa, which seems determined to undermine all the most effective HR programs that are the result of years of steady local and governmental support in Vancouver and now threatens to derail all these programs and spread doubt about their usefulness despite the overwhelmingly positive findings of serous research.

  11. Copernicus, Epicurus, Galileo, and Gassendi.

    Science.gov (United States)

    LoLordo, Antonia

    2015-06-01

    In his Letters on the motion impressed by a moving mover, the theory of the motion of composite bodies put forth by Gassendi is strikingly similar to Galileo's. In other of his writings, however, his description of the motion of individual atoms is understood very differently. In those places, he holds (1) that individual atoms are always in motion, even when the body that contains them is at rest, (2) that atomic motion is discontinuous although the motion of composite bodies is at least apparently continuous, and (3) that atomic motion is grounded in an intrinsic vis motrix, motive power. In contrast, composite bodies simply persist in their state of motion or rest in the absence of outside interference. Unfortunately, Gassendi neglects to explain how his accounts of atomic and composite motion fit together, and it is difficult to see how they could possibly be integrated. My goal is to explain, given this difficulty, why he accepted both the Galilean theory of the motion of composite bodies and the Epicurean theory of atomic motion. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Riccioli Measures the Stars: Observations of the telescopic disks of stars as evidence against Copernicus and Galileo in the middle of the 17th century

    CERN Document Server

    Graney, Christopher M

    2010-01-01

    G. B. Riccioli's 1651 Almagestum Novum contains a table of diameters of stars as measured by Riccioli and his associates with a telescope. The star diameters are spurious, caused by the diffraction of light waves through the circular aperture of the telescope, but astronomers of the time, Riccioli and Galileo Galilei among others, were unaware of this phenomenon and believed that they were seeing the physical bodies of stars. Riccioli used these telescopically measured disks to determine the sizes of stars under both geocentric (or geo-heliocentric/Tychonic) and heliocentric/Copernican hypotheses. The sizes obtained under the Copernican system were immense - dwarfing the Earth, Sun, the Earth's orbit, and even exceeding the distances to the stars given by Tycho Brahe. Thus Riccioli felt that telescopic observations were an effective argument against the Copernican system.

  13. Galileo and Zubiri… The beginning of modern technique The experimental method as a «physical proof of reality»

    Directory of Open Access Journals (Sweden)

    Ricardo Espinoza Lolas

    2017-08-01

    Full Text Available The objective of this article is to analyse the origins of modern Technique in the life and work of Pisan scientist Galileo Galilei (1564-1642 in light of two essential ideas. On the one hand, the events of Galileo’s era(16th and 17th centuries and, on the other, the essential category of «experimentation» as a «physical proof of reality», which appears in Intelligence and Reason (1983 by Xavier Zubiri (1898-1983. From this category of analysis we will be able to see the richness of Galileo’s original technical scientific research and how it has been crucial for the later development of human research throughout History.

  14. Si Galileo Galilei hubiera tenido una cámara digital: enseñando ciencias a una generación digital

    OpenAIRE

    2014-01-01

    El objetivo del presente artículo es mostrar como la cámara digital puede ser una herramienta didáctica para transformar la práctica de educación en ciencias en nuestros salones de clase en el nivel de educación básica. Para ello, se presentan tres casos de proyectos de clase que tienen en común el uso de la cámara digital. Estos casos responden a una teoría de la enseñanza de las ciencias basada en la fundamentación de las prácticas de investigación, cuya herramienta principal es la experime...

  15. 时间与空间:向伽利略致敬%TIME AND SPACE:A TRIBUTE TO GALILEO GALILEI

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    伽利略这位意大利天才在科学历史长河中所扮演了重要角色,他的智慧也为机械制表的发展奠定了扎实基础。"向伽利略致敬"这样一个题目对于一个来自意大利的钟表品牌来说可谓恰如其分——2011年5月19日,意大利高级钟表制造商沛纳海于上海城市雕塑艺术中心正式揭幕了“时间与空间:向伽利略致敬”主题展览,遥远地回应了这位先辈。

  16. Galileo's Medicean Moons (IAU S269)

    Science.gov (United States)

    Barbieri, Cesare; Chakrabarti, Supriya; Coradini, Marcello; Lazzarin, Monica

    2010-11-01

    Preface; 1. Galileo's telescopic observations: the marvel and meaning of discovery George V. Coyne, S. J.; 2. Popular perceptions of Galileo Dava Sobel; 3. The slow growth of humility Tobias Owen and Scott Bolton; 4. A new physics to support the Copernican system. Gleanings from Galileo's works Giulio Peruzzi; 5. The telescope in the making, the Galileo first telescopic observations Alberto Righini; 6. The appearance of the Medicean Moons in 17th century charts and books. How long did it take? Michael Mendillo; 7. Navigation, world mapping and astrometry with Galileo's moons Kaare Aksnes; 8. Modern exploration of Galileo's new worlds Torrence V. Johnson; 9. Medicean Moons sailing through plasma seas: challenges in establishing magnetic properties Margaret G. Kivelson, Xianzhe Jia and Krishan K. Khurana; 10. Aurora on Jupiter: a magnetic connection with the Sun and the Medicean Moons Supriya Chakrabarti and Marina Galand; 11. Io's escaping atmosphere: continuing the legacy of surprise Nicholas M. Schneider; 12. The Jovian Rings Wing-Huen Ip; 13. The Juno mission Scott J. Bolton and the Juno Science Team; 14. Seeking Europa's ocean Robert T. Pappalardo; 15. Europa lander mission: a challenge to find traces of alien life Lev Zelenyi, Oleg Korablev, Elena Vorobyova, Maxim Martynov, Efraim L. Akim and Alexander Zakahrov; 16. Atmospheric moons Galileo would have loved Sushil K. Atreya; 17. The study of Mercury Louise M. Prockter and Peter D. Bedini; 18. Jupiter and the other giants: a comparative study Thérèse Encrenaz; 19. Spectroscopic and spectrometric differentiation between abiotic and biogenic material on icy worlds Kevin P. Hand, Chris McKay and Carl Pilcher; 20. Other worlds, other civilizations? Guy Consolmagno, S. J.; 21. Concluding remarks Roger M. Bonnet; Posters; Author index; Object index.

  17. Galileo: The Added Value for Integrity in Harsh Environments

    Directory of Open Access Journals (Sweden)

    Daniele Borio

    2016-01-01

    Full Text Available A global navigation satellite system (GNSS-based navigation is a challenging task in a signal-degraded environments where GNSS signals are distorted by multipath and attenuated by fading effects: the navigation solution may be inaccurate or unavailable. A possible approach to improve accuracy and availability is the joint use of measurements from different GNSSs and quality check algorithms; this approach is investigated here using live GPS and Galileo signals. A modified receiver autonomous integrity monitoring (RAIM algorithm, including geometry and separability checks, is proposed to detect and exclude erroneous measurements: the multi-constellation approach provides redundant measurements, and RAIM exploits them to exclude distorted observations. The synergy between combined GPS/Galileo navigation and RAIM is analyzed using live data; the performance is compared to the accuracy and availability of a GPS-only solution. The tests performed demonstrate that the methods developed are effective techniques for GNSS-based navigation in signal-degraded environments. The joint use of the multi-constellation approach and of modified RAIM algorithms improves the performance of the navigation system in terms of both accuracy and availability.

  18. Galileo: The Added Value for Integrity in Harsh Environments.

    Science.gov (United States)

    Borio, Daniele; Gioia, Ciro

    2016-01-16

    A global navigation satellite system (GNSS)-based navigation is a challenging task in a signal-degraded environments where GNSS signals are distorted by multipath and attenuated by fading effects: the navigation solution may be inaccurate or unavailable. A possible approach to improve accuracy and availability is the joint use of measurements from different GNSSs and quality check algorithms; this approach is investigated here using live GPS and Galileo signals. A modified receiver autonomous integrity monitoring (RAIM) algorithm, including geometry and separability checks, is proposed to detect and exclude erroneous measurements: the multi-constellation approach provides redundant measurements, and RAIM exploits them to exclude distorted observations. The synergy between combined GPS/Galileo navigation and RAIM is analyzed using live data; the performance is compared to the accuracy and availability of a GPS-only solution. The tests performed demonstrate that the methods developed are effective techniques for GNSS-based navigation in signal-degraded environments. The joint use of the multi-constellation approach and of modified RAIM algorithms improves the performance of the navigation system in terms of both accuracy and availability.

  19. Galileo's mistake a new look at the epic confrontation between galileo and the church

    CERN Document Server

    Rowland, Wade

    2011-01-01

    The modern understanding of the notorious 1633 trial of Galileo is that of Science and Reason persecuted by Ignorance and Superstition-of Galileo as a lonely, courageous freethinker oppressed by a reactionary and anti-intellectual institution fearful of losing its power and influence. But is this an accurate picture? In his provocative reexamination of one of the turning points in the history of science and thought, Wade Rowland contends that the dispute concerned an infinitely more profound question: What is truth and how can we know it? Rowland demonstrates that Galileo's mistak

  20. Galileo Net Flux Radiometer Data Analysis

    Science.gov (United States)

    Sromovsky, Lawrence A.

    1999-01-01

    This report describes analysis of the Galileo Net Flux Radiometer (NFR), an instrument mounted on the Galileo probe, a spacecraft designed for entry into and direct measurements of Jupiter's atmosphere. The grant period for NAG2-1028 began on 1 April 1996, nearly four months after Jupiter atmospheric entry on 7 December 1995, and at which time the probe data were fully recovered and quick look analysis completed. This grant supported the detailed data analysis, resulting in a preliminary paper in Science in May 1996 and a final paper in the journal of Geophysical Research in .September 1998, with conference papers presented within this period.

  1. A statistical characterization of the Galileo-to-GPS inter-system bias

    Science.gov (United States)

    Gioia, Ciro; Borio, Daniele

    2016-11-01

    Global navigation satellite system operates using independent time scales and thus inter-system time offsets have to be determined to enable multi-constellation navigation solutions. GPS/Galileo inter-system bias and drift are evaluated here using different types of receivers: two mass market and two professional receivers. Moreover, three different approaches are considered for the inter-system bias determination: in the first one, the broadcast Galileo to GPS time offset is used to align GPS and Galileo time scales. In the second, the inter-system bias is included in the multi-constellation navigation solution and is estimated using the measurements available. Finally, an enhanced algorithm using constraints on the inter-system bias time evolution is proposed. The inter-system bias estimates obtained with the different approaches are analysed and their stability is experimentally evaluated using the Allan deviation. The impact of the inter-system bias on the position velocity time solution is also considered and the performance of the approaches analysed is evaluated in terms of standard deviation and mean errors for both horizontal and vertical components. From the experiments, it emerges that the inter-system bias is very stable and that the use of constraints, modelling the GPS/Galileo inter-system bias behaviour, significantly improves the performance of multi-constellation navigation.

  2. Galileo Declassified: IOV Spacecraft Metadata and Its Impact on Precise Orbit Determination

    Science.gov (United States)

    Dilssner, Florian; Schönemann, Erik; Springer, Tim; Flohrer, Claudia; Enderle, Werner

    2017-04-01

    In December 2016, shortly after the declaration of Galileo Initial Services, the European GNSS Agency (GSA) disclosed Galileo spacecraft metadata relevant to precise orbit determination (POD), such as antenna phase center parameters, dimensions of the solar panels and the main body, specularity and reflectivity coefficients for the surface materials, yaw attitude steering law, and signal group delays. The metadata relates to the first four operational Galileo satellites, known as the In-Orbit Validation (IOV) satellites, and is publicly available through the European GNSS Service Center (GSC) web site. One of the dataset's major benefits is that it includes nearly all information about the satellites' surface properties needed to develop a physically meaningful analytical solar radiation pressure (SRP) macro model, or "box-wing" (BW) model. Such a BW model for the IOV spacecraft has now been generated for use in NAPEOS, the European Space Operation Centre's (ESOC's) main geodetic software package for POD. The model represents the satellite as a simple six-sided box with two attached panels, or "wings", and allows for the a priori computation of the direct and indirect (Earth albedo) SRP force. Further valuable parameters of the metadata set are the IOV navigation antenna (NAVANT) phase center offsets (PCOs) and variations (PCVs) inferred from pre-launch anechoic chamber measurements. In this work, we report on the validation of the Galileo IOV metadata and its impact on POD, an activity ESOC has been deeply committed to since the launch of the first Galileo experimental satellite, GIOVE-A, in 2005. We first reanalyze the full history of Galileo tracking data the global International GNSS Service (IGS) network has collected since 2012. We generate orbit and clock solutions based on the widely used Empirical CODE Orbit Model (ECOM) with and without the IOV a priori BW model. For the satellite antennas, we apply the new as well as the standard IGS-recommended phase

  3. Galileo, Gauss, and the Green Monster

    Science.gov (United States)

    Kalman, Dan; Teague, Daniel J.

    2013-01-01

    Galileo dropped cannonballs from the leaning tower of Pisa to demonstrate something about falling bodies. Gauss was a giant of mathematics and physics who made unparalleled contributions to both fields. More contemporary (and not a person), the Green Monster is the left-field wall at the home of the Boston Red Sox, Fenway Park. Measuring 37 feet…

  4. Status of Galileo interim radiation electron model

    Science.gov (United States)

    Garrett, H. B.; Jun, I.; Ratliff, J. M.; Evans, R. W.; Clough, G. A.; McEntire, R. W.

    2003-01-01

    Measurements of the high energy, omni-directional electron environment by the Galileo spacecraft Energetic Particle Detector (EDP) were used to develop a new model of Jupiter's trapped electron radiation in the jovian equatorial plane for the range 8 to 16 Jupiter radii.

  5. Matematikken bag satellitnavigation. GPS - GLONASS - GALILEO

    DEFF Research Database (Denmark)

    Hansen, Johan P.

    2012-01-01

    affyringspositionen. Det kostede 12 milliarder US dollars og er nu tilgængeligt for alle. USSR og Kina har tilsvarende militære systemer GLONASS og COMPASS. GALILEO er et nyt europæisk system under udvikling af EU og European Space Agency (20 mia. Euro) med et kommercielt sigte, der forventes at tages i drift i...

  6. Galileo, Gauss, and the Green Monster

    Science.gov (United States)

    Kalman, Dan; Teague, Daniel J.

    2013-01-01

    Galileo dropped cannonballs from the leaning tower of Pisa to demonstrate something about falling bodies. Gauss was a giant of mathematics and physics who made unparalleled contributions to both fields. More contemporary (and not a person), the Green Monster is the left-field wall at the home of the Boston Red Sox, Fenway Park. Measuring 37 feet…

  7. On dynamical realizations of l-conformal Galilei and Newton–Hooke algebras

    Directory of Open Access Journals (Sweden)

    Anton Galajinsky

    2015-07-01

    Full Text Available In two recent papers (Aizawa et al., 2013 [15] and (Aizawa et al., 2015 [16], representation theory of the centrally extended l-conformal Galilei algebra with half-integer l has been applied so as to construct second order differential equations exhibiting the corresponding group as kinematical symmetry. It was suggested to treat them as the Schrödinger equations which involve Hamiltonians describing dynamical systems without higher derivatives. The Hamiltonians possess two unusual features, however. First, they involve the standard kinetic term only for one degree of freedom, while the remaining variables provide contributions linear in momenta. This is typical for Ostrogradsky's canonical approach to the description of higher derivative systems. Second, the Hamiltonian in the second paper is not Hermitian in the conventional sense. In this work, we study the classical limit of the quantum Hamiltonians and demonstrate that the first of them is equivalent to the Hamiltonian describing free higher derivative nonrelativistic particles, while the second can be linked to the Pais–Uhlenbeck oscillator whose frequencies form the arithmetic sequence ωk=(2k−1, k=1,…,n. We also confront the higher derivative models with a genuine second order system constructed in our recent work (Galajinsky and Masterov, 2013 [5] which is discussed in detail for l=32.

  8. Invariant partial differential equations with two-dimensional exotic centrally extended conformal Galilei symmetry

    Science.gov (United States)

    Aizawa, N.; Kuznetsova, Z.; Toppan, F.

    2016-04-01

    Conformal Galilei algebras (CGAs) labeled by d, ℓ (where d is the number of space dimensions and ℓ denotes a spin-ℓ representation w.r.t. the 𝔰𝔩(2) subalgebra) admit two types of central extensions, the ordinary one (for any d and half-integer ℓ) and the exotic central extension which only exists for d = 2 and ℓ ∈ ℕ. For both types of central extensions, invariant second-order partial differential equations (PDEs) with continuous spectrum were constructed by Aizawa et al. [J. Phys. A 46, 405204 (2013)]. It was later proved by Aizawa et al. [J. Math. Phys. 3, 031701 (2015)] that the ordinary central extensions also lead to oscillator-like PDEs with discrete spectrum. We close in this paper the existing gap, constructing a new class of second-order invariant PDEs for the exotic centrally extended CGAs; they admit a discrete and bounded spectrum when applied to a lowest weight representation. These PDEs are markedly different with respect to their ordinary counterparts. The ℓ = 1 case (which is the prototype of this class of extensions, just like the ℓ = /1 2 Schrödinger algebra is the prototype of the ordinary centrally extended CGAs) is analyzed in detail.

  9. On dynamical realizations of l-conformal Galilei and Newton-Hooke algebras

    Science.gov (United States)

    Galajinsky, Anton; Masterov, Ivan

    2015-07-01

    In two recent papers (Aizawa et al., 2013 [15]) and (Aizawa et al., 2015 [16]), representation theory of the centrally extended l-conformal Galilei algebra with half-integer l has been applied so as to construct second order differential equations exhibiting the corresponding group as kinematical symmetry. It was suggested to treat them as the Schrödinger equations which involve Hamiltonians describing dynamical systems without higher derivatives. The Hamiltonians possess two unusual features, however. First, they involve the standard kinetic term only for one degree of freedom, while the remaining variables provide contributions linear in momenta. This is typical for Ostrogradsky's canonical approach to the description of higher derivative systems. Second, the Hamiltonian in the second paper is not Hermitian in the conventional sense. In this work, we study the classical limit of the quantum Hamiltonians and demonstrate that the first of them is equivalent to the Hamiltonian describing free higher derivative nonrelativistic particles, while the second can be linked to the Pais-Uhlenbeck oscillator whose frequencies form the arithmetic sequence ωk = (2 k - 1), k = 1, …, n. We also confront the higher derivative models with a genuine second order system constructed in our recent work (Galajinsky and Masterov, 2013 [5]) which is discussed in detail for l =3/2.

  10. Io plasma torus ion composition: Voyager, Galileo, and Cassini

    Science.gov (United States)

    Nerney, Edward G.; Bagenal, Fran; Steffl, Andrew J.

    2017-01-01

    The Io torus produces ultraviolet emissions diagnostic of plasma conditions. We revisit data sets obtained by the Voyager 1, Galileo, and Cassini missions at Jupiter. With the latest version (8.0) of the CHIANTI atomic database we analyze UV spectra to determine ion composition. We compare ion composition obtained from observations from these three missions with a theoretical model of the physical chemistry of the torus by Delamere et al. (2005). We find ion abundances from the Voyager data similar to the Cassini epoch, consistent with the dissociation and ionization of SO2, but with a slightly higher average ionization state for sulfur, consistent with the higher electron temperature measured by Voyager. This reanalysis of the Voyager data produces a much lower oxygen:sulfur ratio than earlier analysis by Shemansky (1988), which was also reported by Bagenal (1994). We derive fractional ion compositions in the center of the torus to be S+/Ne 5%, S++/Ne 20%, S+++/Ne 5%, O+/Ne 20%, O++/Ne 3%, and Σ(On+)/Σ(Sn+) 0.8, leaving about 10-15% of the charge as protons. The radial profile of ion composition indicates a slightly higher average ionization state, a modest loss of sulfur relative to oxygen, and Σ(On+)/Σ(Sn+) 1.2 at about 8 RJ, beyond which the composition is basically frozen in. The Galileo observations of UV emissions from the torus suggest that the composition in June 1996 may have comprised a lower abundance of oxygen than usual, consistent with observations made at the same time by the EUVE satellite.

  11. GEO-6 project for Galileo data scientific utilization

    Science.gov (United States)

    Buresova, Dalia; Lastovicka, Jan; Boska, Josef; Sauli, Petra; Kouba, Daniel; Mosna, Zbysek

    The future GNSS Galileo system offer a number of benefits (e.g. availability of better accuracy positioning, new frequencies bands allowing the implementation of specific techniques, provable time-stamp and location data using SIS authorisation, integrity, better support ad-hoc algorithms for data analysis and other service guarantee for liability and regulated applications) are widely spread among different disciplines. Also applications which are less interesting from the commercial and market point of view could successfully contribute to the numerous social benefits and support the innovation in the international research. The aim of the GEO-6 project "Scientific research Using GNSS" is to propose and broaden scientific utilization of future GNSS Galileo system data in research. It is a joint project of seven institutions from six countries led by the Atos Origin Company from Spain. The core of the project consists from six projects in five priority areas: PA-1 Remote sensing of the ocean using GNSS reflections, PA-2a Investigating GNSS ionospheric data assimilation, PA-2b 3-D gravity wave detection and determination (both PA-2a and PA-2b are ionospheric topics), PA-3 Demonstration of capability for operational forecasting of atmospheric delays, PA-4 GNSS seismometer, PA-5 Spacecraft formation flying using global navigation satellite systems. Institute of Atmospheric Physics, Prague, Czech Republic is responsible for the project PA-2b, where we developed and tested (to the extent allowed by available data) an algorithm and computer code for the 3-D detection of gravity waves and determination of their characteristics. The main drivers of the GEO-6 project are: high levels of accuracy even with the support of local elements, sharing of solutions and results for the worldwide scientific community. The paper will present basic description of the project with more details concerning Czech participation in it.

  12. ACCURACY ASSESSMENT OF COMBINED GPS/GALILEO SINGLE POINT POSITIONING%GPS/GALILEO组合单点定位精度分析

    Institute of Scientific and Technical Information of China (English)

    罗小敏; 蔡昌盛

    2013-01-01

    建立了GPS/GALILEO组合单点定位的数学模型,在对各项误差改正的基础上,利用全球多卫星导航系统试验网跟踪站的观测数据,对GPS/GALILEO组合单点定位模型进行了试算.结果表明,当GPS观测卫星较充足时,增加1~2颗GALILEO观测卫星并不能有效地提高组合GPS/GALILEO定位的精度,当GPS观测卫星较少时,组合GPS/GALILEO系统相比单GPS系统,定位精度有较明显的改善.%A mathematic model of combined GPS/GALILEO single point positioning (SPP) is developed.On the basis of error corrections,the combined GPS/GALILEO SPP model is tested using the data of the MGEX tracking stations.The results indicate that the accuracy of the GPS/GALILEO SPP is not significantly improved when adding only one or two GALILEO satellites when the GPS observation satellites are sufficient.However,in the condition of insufficient number of GPS satellites,the accuracy of the combined GPS/GALILEO SPP is better than the GPS-onlv SPP.

  13. Analysis of Galileo Style Geostationary Satellite Imaging: Image Reconstruction

    Science.gov (United States)

    2012-09-01

    obtained using only baselines longer than 8 m does not sample the short spacial frequencies, and the image reconstruction is not able to recover the...the long spacial frequencies sampled in a shorter baseline overlap the short spacial frequencies sampled in a longer baseline. This technique will

  14. GalileoMobile: Astronomical activities in schools

    Science.gov (United States)

    Dasi Espuig, Maria; Vasquez, Mayte; Kobel, Philippe

    GalileoMobile is an itinerant science education initiative run on a voluntary basis by an international team of astronomers, educators, and science communicators. Our team's main goal is to make astronomy accessible to schools and communities around the globe that have little or no access to outreach actions. We do this by performing teacher workshops, activities with students, and donating educational material. Since the creation of GalileoMobile in 2008, we have travelled to Chile, Bolivia, Peru, India, and Uganda, and worked with 56 schools in total. Our activities are centred on the GalileoMobile Handbook of Activities that comprises around 20 astronomical activities which we adapted from many different sources, and translated into 4 languages. The experience we gained in Chile, Bolivia, Peru, India, and Uganda taught us that (1) bringing experts from other countries was very stimulating for children as they are naturally curious about other cultures and encourages a collaboration beyond borders; (2) high-school students who were already interested in science were always very eager to interact with real astronomers doing research to ask for career advice; (3) inquiry-based methods are important to make the learning process more effective and we have therefore, re-adapted the activities in our Handbook according to these; (4) local teachers and university students involved in our activities have the potential to carry out follow-up activities, and examples are those from Uganda and India.

  15. Active Volcanism on Io as Seen by Galileo SSI

    Science.gov (United States)

    McEwen, A.S.; Keszthelyi, L.; Geissler, P.; Simonelli, D.P.; Carr, M.H.; Johnson, T.V.; Klaasen, K.P.; Breneman, H.H.; Jones, T.J.; Kaufman, J.M.; Magee, K.P.; Senske, D.A.; Belton, M.J.S.; Schubert, G.

    1998-01-01

    Active volcanism on Io has been monitored during the nominal Galileo satellite tour from mid 1996 through late 1997. The Solid State Imaging (SSI) experiment was able to observe many manifestations of this active volcanism, including (1) changes in the color and albedo of the surface, (2) active airborne plumes, and (3) glowing vents seen in eclipse. About 30 large-scale (tens of kilometers) surface changes are obvious from comparison of the SSI images to those acquired by Voyager in 1979. These include new pyroclastic deposits of several colors, bright and dark flows, and caldera-floor materials. There have also been significant surface changes on Io during the Galileo mission itself, such as a new 400-km-diameter dark pyroclastic deposit around Pillan Patera. While these surface changes are impressive, the number of large-scale changes observed in the four months between the Voyager 1 and Voyager 2 flybys in 1979 suggested that over 17 years the cumulative changes would have been much more impressive. There are two reasons why this was not actually the case. First, it appears that the most widespread plume deposits are ephemeral and seem to disappear within a few years. Second, it appears that a large fraction of the volcanic activity is confined to repeated resurfacing of dark calderas and flow fields that cover only a few percent of Io's surface. The plume monitoring has revealed 10 active plumes, comparable to the 9 plumes observed by Voyager. One of these plumes was visible only in the first orbit and three became active in the later orbits. Only the Prometheus plume has been consistently active and easy to detect. Observations of the Pele plume have been particularly intriguing since it was detected only once by SSI, despite repeated attempts, but has been detected several times by the Hubble Space Telescope at 255 nm. Pele's plume is much taller (460 km) than during Voyager 1 (300 km) and much fainter at visible wavelengths. Prometheus-type plumes (50

  16. The Galileo System of Measurement: Preliminary Evidence for Precision, Stability, and Equivalance to Traditional Measures

    Science.gov (United States)

    Gillham, James; Woelfel, Joseph

    1977-01-01

    Describes the Galileo system of measurement operations including reliability and validity data. Illustrations of some of the relations between Galileo measures and traditional procedures are provided. (MH)

  17. Research on the intersystem interference between COMPASS and Galileo%COMPASS和Galileo系统间信号干扰研究

    Institute of Scientific and Technical Information of China (English)

    胡媛; 刘卫

    2012-01-01

    随着各国和地区的卫星导航系统建设.我国北斗COMPASS和欧盟Galileo系统间信号干扰已成为广泛关注的焦点。首先建立有效评价卫星导航系统间信号干扰的方法,其次分析COMPASS和Galileo系统的星座构型和信号体制参数,最后对两大系统间的民用信号间干扰进行仿真分析,结果表明COMPASS信号的引入对Galileo造成干扰,但其造成的干扰比Galileo对COMPASS的干扰小。所建立的评价方法和结果可为导航系统的信号体制设计和接收机应用提供理论参考。%With the development of satellite navigation system in many countries and regions, the intersystem interference between Chinese COMPASS and EU's Galileo has become a matter of great concern for the system providers and user communities. First, an effective evaluation method for signal interference among satellite navigation systems is established. Second, the constellation configuration and signal parameters of COMPASS and Galileo are analyzed. Finally, real simulations accounting for the interference effects between Galileo and COMPASS are carried out. All results show that COMPASS introduces intersystem interference to Galileo, but the interference effects are lower than Galileo interfered to COMPASS signals. The evaluation method and results can provide a theoretical reference for signal structure design and receiver apply.

  18. Galileo observations of volcanic plumes on Io

    Science.gov (United States)

    Geissler, P.E.; McMillan, M.T.

    2008-01-01

    Io's volcanic plumes erupt in a dazzling variety of sizes, shapes, colors and opacities. In general, the plumes fall into two classes, representing distinct source gas temperatures. Most of the Galileo imaging observations were of the smaller, more numerous Prometheus-type plumes that are produced when hot flows of silicate lava impinge on volatile surface ices of SO2. Few detections were made of the giant, Pele-type plumes that vent high temperature, sulfur-rich gases from the interior of Io; this was partly because of the insensitivity of Galileo's camera to ultraviolet wavelengths. Both gas and dust spout from plumes of each class. Favorably located gas plumes were detected during eclipse, when Io was in Jupiter's shadow. Dense dust columns were imaged in daylight above several Prometheus-type eruptions, reaching heights typically less than 100 km. Comparisons between eclipse observations, sunlit images, and the record of surface changes show that these optically thick dust columns are much smaller in stature than the corresponding gas plumes but are adequate to produce the observed surface deposits. Mie scattering calculations suggest that these conspicuous dust plumes are made up of coarse grained “ash” particles with radii on the order of 100 nm, and total masses on the order of 106 kg per plume. Long exposure images of Thor in sunlight show a faint outer envelope apparently populated by particles small enough to be carried along with the gas flow, perhaps formed by condensation of sulfurous “snowflakes” as suggested by the plasma instrumentation aboard Galileo as it flew through Thor's plume [Frank, L.A., Paterson, W.R., 2002. J. Geophys. Res. (Space Phys.) 107, doi:10.1029/2002JA009240. 31-1]. If so, the total mass of these fine, nearly invisible particles may be comparable to the mass of the gas, and could account for much of Io's rapid resurfacing.

  19. GNSS-SDR, un ricevitore software completamente open-source pronto per GALILEO

    Directory of Open Access Journals (Sweden)

    Mara Branzanti

    2014-05-01

    Full Text Available With the advent of new in-orbit satellites, the landscape of GNSS is going to change rapidly and thereceiver architectures must continuously be able to exploit the full potential of the forthcoming scenarios. For such reasons, the SDR (Software Defined Receiver philosophy have a great response in the GNSS applications.Here, the first open source SDR software (GNSS-SDR ready for the Galileo constellation is presented, together with its participation in the Google Summer of Code.

  20. GNSS-SDR, un ricevitore software completamente open-source pronto per GALILEO

    OpenAIRE

    Mara Branzanti

    2014-01-01

    With the advent of new in-orbit satellites, the landscape of GNSS is going to change rapidly and thereceiver architectures must continuously be able to exploit the full potential of the forthcoming scenarios. For such reasons, the SDR (Software Defined Receiver) philosophy have a great response in the GNSS applications.Here, the first open source SDR software (GNSS-SDR) ready for the Galileo constellation is presented, together with its participation in the Google Summer of Code.

  1. The four hundred years of planetary science since Galileo and Kepler.

    Science.gov (United States)

    Burns, Joseph A

    2010-07-29

    For 350 years after Galileo's discoveries, ground-based telescopes and theoretical modelling furnished everything we knew about the Sun's planetary retinue. Over the past five decades, however, spacecraft visits to many targets transformed these early notions, revealing the diversity of Solar System bodies and displaying active planetary processes at work. Violent events have punctuated the histories of many planets and satellites, changing them substantially since their birth. Contemporary knowledge has finally allowed testable models of the Solar System's origin to be developed and potential abodes for extraterrestrial life to be explored. Future planetary research should involve focused studies of selected targets, including exoplanets.

  2. Galileo infrared imaging spectroscopy measurements at venus

    Science.gov (United States)

    Carlson, R.W.; Baines, K.H.; Encrenaz, Th.; Taylor, F.W.; Drossart, P.; Kamp, L.W.; Pollack, James B.; Lellouch, E.; Collard, A.D.; Calcutt, S.B.; Grinspoon, D.; Weissman, P.R.; Smythe, W.D.; Ocampo, A.C.; Danielson, G.E.; Fanale, F.P.; Johnson, T.V.; Kieffer, H.H.; Matson, D.L.; McCord, T.B.; Soderblom, L.A.

    1991-01-01

    During the 1990 Galileo Venus flyby, the Near Infrared Mapping Spectrometer investigated the night-side atmosphere of Venus in the spectral range 0.7 to 5.2 micrometers. Multispectral images at high spatial resolution indicate substantial cloud opacity variations in the lower cloud levels, centered at 50 kilometers altitude. Zonal and meridional winds were derived for this level and are consistent with motion of the upper branch of a Hadley cell. Northern and southern hemisphere clouds appear to be markedly different. Spectral profiles were used to derive lower atmosphere abundances of water vapor and other species.

  3. Galileo's Treatment for the Centre of Gravity of Solids

    Science.gov (United States)

    Worner, C. H.; Iommi-Amunategui, G.

    2007-01-01

    The appendix on the centres of gravity that appears at the end of Galileo's book, "Two New Sciences", is analysed. It is shown that the method used by Galileo in this work has an interesting reasoning and also shows preliminary ideas about scaling and advances some ideas about series convergence. In addition, we note that the geometrical language…

  4. A Galilean Approach to the Galileo Affair, 1609-2009

    Science.gov (United States)

    Finocchiaro, Maurice A.

    2011-01-01

    Galileo's telescopic discoveries of 1609-1612 provided a crucial, although not conclusive, confirmation of the Copernican hypothesis of the earth's motion. In Galileo's approach, the Copernican Revolution required that the geokinetic hypothesis be supported not only with new theoretical arguments but also with new observational evidence; that it…

  5. Galileo in early modern Denmark, 1600-1650

    CERN Document Server

    Kragh, Helge

    2014-01-01

    The scientific revolution in the first half of the seventeenth century, pioneered by figures such as Harvey, Galileo, Gassendi, Kepler and Descartes, was disseminated to the northernmost countries in Europe with considerable delay. In this essay I examine how and when Galileo's new ideas in physics and astronomy became known in Denmark, and I compare the reception with the one in Sweden. It turns out that Galileo was almost exclusively known for his sensational use of the telescope to unravel the secrets of the heavens, meaning that he was predominantly seen as an astronomical innovator and advocate of the Copernican world system. Danish astronomy at the time was however based on Tycho Brahe's view of the universe and therefore hostile to Copernican and, by implication, Galilean cosmology. Although Galileo's telescope attracted much attention, it took about thirty years until a Danish astronomer actually used the instrument for observations. By the 1640s Galileo was generally admired for his astronomical disc...

  6. Galileo and the equations of motion

    CERN Document Server

    Boccaletti, Dino

    2016-01-01

    This book is intended as a historical and critical study on the origin of the equations of motion as established in Newton's Principia. The central question that it aims to answer is whether it is indeed correct to ascribe to Galileo the inertia principle and the law of falling bodies. In order to accomplish this task, the study begins by considering theories on the motion of bodies from classical antiquity, and especially those of Aristotle. The theories developed during the Middle Ages and the Renaissance are then reviewed, with careful analysis of the contributions of, for example, the Merton and Parisian Schools and Galileo’s immediate predecessors, Tartaglia and Benedetti. Finally, Galileo’s work is examined in detail, starting from the early writings.  Excerpts from individual works are presented, to allow the texts to speak for themselves, and then commented upon. The book provides historical evidence both for Galileo's dependence on his forerunners and for the major breakthroughs that he achieved...

  7. LARES succesfully launched in orbit: satellite and mission description

    CERN Document Server

    Paolozzi, Antonio

    2013-01-01

    On February 13th 2012, the LARES satellite of the Italian Space Agency (ASI) was launched into orbit with the qualification flight of the new VEGA launcher of the European Space Agency (ESA). The payload was released very accurately in the nominal orbit. The name LARES means LAser RElativity Satellite and summarises the objective of the mission and some characteristics of the satellite. It is, in fact, a mission designed to test Einstein's General Relativity Theory (specifically 'frame dragging' and Lense-Thirring effect). The satellite is passive and covered with optical retroreflectors that send back laser pulses to the emitting ground station. This allows accurate positioning of the satellite, which is important for measuring the very small deviations from Galilei-Newton's laws. In 2008, ASI selected the prime industrial contractor for the LARES system with a heavy involvement of the universities in all phases of the programme, from the design to the construction and testing of the satellite and separation...

  8. Imaging of volcanic activity on Jupiter's moon Io by Galileo during the Galileo Europa Mission and the Galileo Millennium Mission

    Science.gov (United States)

    Keszthelyi, L.; McEwen, A.S.; Phillips, C.B.; Milazzo, M.; Geissler, P.; Turtle, E.P.; Radebaugh, J.; Williams, D.A.; Simonelli, D.P.; Breneman, H.H.; Klaasen, K.P.; Levanas, G.; Denk, T.; Alexander, D.D.A.; Capraro, K.; Chang, S.-H.; Chen, A.C.; Clark, J.; Conner, D.L.; Culver, A.; Handley, T.H.; Jensen, D.N.; Knight, D.D.; LaVoie, S.K.; McAuley, M.; Mego, V.; Montoya, O.; Mortensen, H.B.; Noland, S.J.; Patel, R.R.; Pauro, T.M.; Stanley, C.L.; Steinwand, D.J.; Thaller, T.F.; Woncik, P.J.; Yagi, G.M.; Yoshimizu, J.R.; Alvarez, Del; Castillo, E.M.; Belton, M.J.S.; Beyer, R.; Branston, D.; Fishburn, M.B.; Mueller, B.; Ragan, R.; Samarasinha, N.; Anger, C.D.; Cunningham, C.; Little, B.; Arriola, S.; Carr, M.H.; Asphaug, E.; Moore, J.; Morrison, D.; Rages, K.; Banfield, D.; Bell, M.; Burns, J.A.; Carcich, B.; Clark, B.; Currier, N.; Dauber, I.; Gierasch, P.J.; Helfenstein, P.; Mann, M.; Othman, O.; Rossier, L.; Solomon, N.; Sullivan, R.; Thomas, P.C.; Veverka, J.; Becker, T.; Edwards, K.; Gaddis, L.; Kirk, R.; Lee, E.; Rosanova, T.; Sucharski, R.M.; Beebe, R.F.; Simon, A.; Bender, K.; Chuang, F.; Fagents, S.; Figueredo, P.; Greeley, R.; Homan, K.; Kadel, S.; Kerr, J.; Klemaszewski, J.; Lo, E.; Schwarz, W.; Williams, K.; Bierhaus, E.; Brooks, S.; Chapman, C.R.; Merline, B.; Keller, J.; Schenk, P.; Tamblyn, P.; Bouchez, A.; Dyundian, U.; Ingersoll, A.P.; Showman, A.; Spitale, J.; Stewart, S.; Vasavada, A.; Cunningham, W.F.; Johnson, T.V.; Jones, T.J.; Kaufman, J.M.; Magee, K.P.; Meredith, M.K.; Orton, G.S.; Senske, D.A.; West, A.; Winther, D.; Collins, G.; Fripp, W.J.; Head, J. W.; Pappalardo, R.; Pratt, S.; Procter, L.; Spaun, N.; Colvin, T.; Davies, M.; DeJong, E.M.; Hall, J.; Suzuki, S.; Gorjian, Z.; Giese, B.; Koehler, U.; Neukum, G.; Oberst, J.; Roatsch, T.; Tost, W.; Schuster, P.; Wagner, R.; Dieter, N.; Durda, D.; Greenberg, R.J.; Hoppa, G.; Jaeger, W.; Plassman, J.; Tufts, R.; Fanale, F.P.; Gran,

    2001-01-01

    The Solid-State Imaging (SSI) instrument provided the first high- and medium-resolution views of Io as the Galileo spacecraft closed in on the volcanic body in late 1999 and early 2000. While each volcanic center has many unique features, the majority can be placed into one of two broad categories. The "Promethean" eruptions, typified by the volcanic center Prometheus, are characterized by long-lived steady eruptions producing a compound flow field emplaced in an insulating manner over a period of years to decades. In contrast, "Pillanian" eruptions are characterized by large pyroclastic deposits and short-lived but high effusion rate eruptions from fissures feeding open-channel or open-sheet flows. Both types of eruptions commonly have ???100-km-tall, bright, SO2-rich plumes forming near the flow fronts and smaller deposits of red material that mark the vent for the silicate lavas. Copyright 2001 by the American Geophysical Union.

  9. Global Ionospheric Modelling using Multi-GNSS: BeiDou, Galileo, GLONASS and GPS

    Science.gov (United States)

    Ren, Xiaodong; Zhang, Xiaohong; Xie, Weiliang; Zhang, Keke; Yuan, Yongqiang; Li, Xingxing

    2016-09-01

    The emergence of China’s Beidou, Europe’s Galileo and Russia’s GLONASS satellites has multiplied the number of ionospheric piercing points (IPP) offered by GPS alone. This provides great opportunities for deriving precise global ionospheric maps (GIMs) with high resolution to improve positioning accuracy and ionospheric monitoring capabilities. In this paper, the GIM is developed based on multi-GNSS (GPS, GLONASS, BeiDou and Galileo) observations in the current multi-constellation condition. The performance and contribution of multi-GNSS for ionospheric modelling are carefully analysed and evaluated. Multi-GNSS observations of over 300 stations from the Multi-GNSS Experiment (MGEX) and International GNSS Service (IGS) networks for two months are processed. The results show that the multi-GNSS GIM products are better than those of GIM products based on GPS-only. Differential code biases (DCB) are by-products of the multi-GNSS ionosphere modelling, the corresponding standard deviations (STDs) are 0.06 ns, 0.10 ns, 0.18 ns and 0.15 ns for GPS, GLONASS, BeiDou and Galileo, respectively in satellite, and the STDs for the receiver are approximately 0.2~0.4 ns. The single-frequency precise point positioning (SF-PPP) results indicate that the ionospheric modelling accuracy of the proposed method based on multi-GNSS observations is better than that of the current dual-system GIM in specific areas.

  10. What Would Galileo Do? An Update on the Galileo Teacher Training Program

    Science.gov (United States)

    Kruse, B.; Manning, J. G.; Schultz, G.; Fraknoi, A.

    2012-08-01

    The Galileo Teacher Training Program (GTTP) is a heritage program of the International Year of Astronomy (IYA) and Beyond that provides professional development for teachers in grades 3-12. At the core of every GTTP workshop are activities inspired by Galileo's iconic observations, IYA and NASA resources and activities, activities related to fundamental concepts to assist teachers in meeting their curriculum goals, and the inclusion of resources adaptable for use in the classroom. GTTP actively utilizes a hands-on, inquiry based collaborative activity model of learning, modeling effective techniques for engaging student interest and promoting scientific literacy for both content and process. This article includes lessons learned from the pilot and following workshops and plans to take the concept forward in flexible and adaptive ways.

  11. Galileo in Rome the rise and fall of a troublesome genius

    CERN Document Server

    Shea, William R

    2003-01-01

    A detailed, revisionist study of the life and career of the great Italian scientist offers a focused analysis of Galileo''s relationship with the Catholic Church, discussing the theological furor caused by Galileo''s Dialogue, the scientist''s own role in the conflict, and the events of his trial by the Inquisition. (Biography).

  12. Galileo Press Conference from JPL. Parts 1 and 2

    Science.gov (United States)

    1992-01-01

    This two-tape Jet Propulsion Laboratory (JPL) video production presents a Dec. 8, 1992 press conference held at JPL to discuss the final Galileo spacecraft encounter with Earth before beginning its journey to Jupiter. The main theme of the conference was centered on the significance of the 2nd and final Earth/Moon flyby as being the spacecraft's last planetary encounter in the solar system before reaching Jupiter, as well as final flight preparations prior to its final journey. Each person of the five member panel was introduced by Robert MacMillan (JPL Public Information Mgr.) before giving brief presentations including slides and viewgraphs covering their area of expertise regarding Galileo's current status and future plans. After the presentations, the media was given an opportunity to ask questions of the panel regarding the mission. Mr. Wesley Huntress (Dir. of Solar System Exploration (NASA)), William J. ONeill (Galileo Project Manager), Neal E. Ausman, Jr. (Galileo Mission Director), Dr. Torrence V. Johnson (Galileo Project Scientist) and Dr. Ronald Greeley (Member, Imaging Team, Colorado St. Univ.) made up the panel and discussed topics including: Galileo's interplanetary trajectory; project status and performance review; instrument calibration activities; mission timelines; lunar observation and imaging; and general lunar science. Also included in the last three minutes of the video are simulations and images of the 2nd Galileo/Moon encounter.

  13. The chemical composition of the Galileian satellites

    CERN Document Server

    Celebonovic, V

    1998-01-01

    Using the semiclassical theory of dense matter proposed by P.Savic and R.Kasanin,the mean molecular masses of the Galilean satellites of Jupiter are determined.The calculated values are fitted by plausible combinations of chemical elements,and the results are in good agreement with the observations by "Galileo".Possible cosmogonical explanations are briefly discussed.

  14. Questions of Modern Cosmology Galileo's Legacy

    CERN Document Server

    D'Onofrio, Mauro

    2009-01-01

    Are we living in the "golden age" of cosmology? Are we close to understanding the nature of the unknown ingredients of the currently most accepted cosmological model and the physics of the early Universe? Or are we instead approaching a paradigm shift? What is dark matter and does it exist? How is it distributed around galaxies and clusters? Is the scientific community open to alternative ideas that may prompt a new scientific revolution - as the Copernican revolution did in Galileo's time? Do other types of supernovae exist that can be of interest for cosmology? Why have quasars never been effectively used as standard candles? Can you tell us about the scientific adventure of COBE? How does the extraction of the Cosmic Microwave Background anisotropy depend on the subtraction of the various astrophysical foregrounds? These, among many others, are the astrophysical, philosophical and sociological questions surrounding modern cosmology and the scientific community that Mauro D'Onofrio and Carlo Burigana pose t...

  15. The cognitive development of Galileo's theory of buoyancy

    Science.gov (United States)

    Palmieri, Paolo

    2005-01-01

    Some thirty years ago, in a seminal book, William Shea argued that between 1610 and 1632 Galileo worked out "the methodology of his intellectual revolution", and that hydrostatics was one fundamental area of research Galileo concerned himself with at that time. According to Shea, that methodology was deeply rooted in Archimedean mathematics and basically consisted in mathematically investigating classes of phenomena, such as floating bodies, under certain idealized conditions. I believe that Shea's view is fundamentally correct. I will develop it further, by reconsidering Galileo's methodology in finer detail, specifically in relation to the development of his theory of floating bodies.

  16. Storyboard GALILEO CRUISE SCIENCE OPPORTUNITIES describes asteroid encounters

    Science.gov (United States)

    1989-01-01

    Storyboard with mosaicked image of an asteroid and entitled GALILEO CRUISE SCIENCE OPPORTUNITIES describes asteroid objectives. These objectives include: first asteroid encounter; surface geology, composition size, shape, mass; and relation of primitive bodies to meteorites.

  17. Modeling Io's Heat Flow: Constraints from Galileo PPR Data

    Science.gov (United States)

    Rathbun, J. A.; Spencer, J. R.; Tamppari, L. K.

    2000-01-01

    We attempt to improve on previous Io heat flow estimates by using higher resolution data from Galileo Photopolarimeter Radiometer (PPR) and improved thermophysical models of the surface, including finite thermal inertia, the pedestal effect, and disk-resolved radiance.

  18. Io's Diverse Styles of Volcanic Activity: Results from Galileo NIMS

    Science.gov (United States)

    Lopes, R. M. C.; Smythe, W. D.; Kamp, L. W.; Doute, S.; Carlson, R.; McEwen, A.; Geissler, P.

    2001-01-01

    Observations by Galileo's Near-Infrared Mapping Spectrometer were used to map the thermal structure of several of Io's hot spots, revealing different styles of volcanism Additional information is contained in the original extended abstract..

  19. GALILEO with high eccentricity and equipped by Accelerometers:a tool for GR experiments

    Science.gov (United States)

    Vespe, Francesco

    2015-08-01

    In the last years three ingredients have enlarged the spectrum of scientific applications based on space techniques: the big number of satellites devoted to Space Geodesy and Earth Observation, the tremendous improvement of the Earth gravity field models due to CHAMP, GRACE and GOCE missions and the application of the Gravity Field Free technique (GFF). The last ingredient was applied for the first time to measure the Lense Thirring gravitomagnetic field (L-T). Essentially a linear combination of "n" orbital parameters of LAGEOS I & II satellites [1] was performed in order to cancel the contribution of the first (n-1) even zonals of the gravity field. The chance to put aboard GALILEO accelerometers (AoG) and the "unhappy" injection of two satellites on wrong highly eccentric orbits can make the direct involvement of GNSS satellites in scientific investigations more and more essential. We will investigate how all these ingredients can improve the quality of General Relativistic tests by using Space Geodesy satellites.

  20. Galileo Photometry of Asteroid 951 Gaspra

    Science.gov (United States)

    Helfenstein, P.; Veverka, J.; Thomas, P.C.; Simonelli, D.P.; Lee, P.; Klaasen, K.; Johnson, T.V.; Breneman, H.; Head, J.W.; Murchie, S.; Fanale, F.; Robinson, M.; Clark, B.; Granahan, J.; Garbeil, H.; McEwen, A.S.; Kirk, R.L.; Davies, M.; Neukum, G.; Mottola, S.; Wagner, R.; Belton, M.; Chapman, C.; Pilcher, C.

    1994-01-01

    Galileo images of Gaspra make it possible for the first time to determine a main-belt asteroid's photometric properties accurately by providing surface-resolved coverage over a wide range of incidence and emission angles and by extending the phase angle coverage to phases not observable from Earth. We combine Earth-based telescopic photometry over phase angles 2?? ??? ?? ??? 25?? with Galileo whole-disk and disk-resolved data at 33?? ??? ?? ??? 51?? to derive average global photometric properties in terms of Hapke's photometric model. The microscopic texture and particle phase-function behavior of Gaspra's surface are remarkably like those of other airless rocky bodies such as the Moon. The macroscopic surface roughness parameter, ??̄ = 29??, is slightly larger than that reported for typical lunar materials. The particle single scattering albedo, ??́0 = 0.36 ?? 0.07, is significantly larger than for lunar materials, and the opposition surge amplitude, B0 = 1.63 ?? 0.07, is correspondingly smaller. We determine a visual geometric albedo pv = 0.22 ?? 0.06 for Gaspra, in close agreement with pv = 0.22 ?? 0.03 estimated from Earth-based observations. Gaspra's phase integral is 0.47, and the bolometric Bond albedo is estimated to be 0.12 ?? 0.03. An albedo map derived by correcting Galileo images with our average global photometric function reveals subdued albedo contrasts of ??10% or less over Gaspra's northern hemisphere. Several independent classification algorithms confirm the subtle spectral heterogeneity reported earlier (S. Mottola, M. DiMartino, M. Gonano-Beurer, H. Hoffman, and G. Neukum, 1993, Asteroids, Comets, Meteors, pp. 421-424; M. J. S. Belton et al., 1992, Science 257, 1647-1652). Whole-disk colors (0.41 ??? ?? ??? 0.99 ??m) vary systematically with longitude by about ??5%, but color differences as large as 30% occur locally. Colors vary continuously between end-member materials whose areal distribution correlates with regional topography. Infrared

  1. Comparación de los valores del espesor corneal central según los equipos Lenstar, Galilei y Pentacam Comparative study of the central corneal thickness measurements taken by Lenstar, Gallilei and Pentacam equipment

    Directory of Open Access Journals (Sweden)

    Iramis Miranda Hernández

    2012-06-01

    Full Text Available Objetivo: Comparar valores del espesor corneal central obtenidos mediante la paquimetría con el sistema de interferometria de coherencia parcial (Lenstar con los sistemas Scheimpflug (Pentacam; Oculus y Galilei (Ziemer, Suiza. Métodos: Se realizó un estudio prospectivo, comparativo en 120 ojos de 60 pacientes. Para la comparación se tomaron varias mediciones recomendadas por los fabricantes para probar la eficacia del equipo con el nuevo biómetro Lenstar LS 900 (Haag Streit AG y con los equipos Pentacam y Galilei. La comparación de los valores se realizó mediante el análisis de regresión lineal y correlación de Pearson. Resultados: El análisis reveló que existe una alta correspondencia en los valores del espesor corneal central entre Lenstar y los topógrafos Galilei y Pentacam. Conclusiones: Existe una alta correspondencia entre los valores del espesor corneal central obtenidos por los equipos Lenstar, Pentacam y Galilei. Por esto el equipo Lenstar es útil en la cirugía de catarata y la cirugía refractiva.Objective: To compare the central corneal thickness measurements taken by pachimetry with the partial coherence interferometry, Lenstar and with Scheimpflug systems (Pentacam; Oculus and Galilei (Ziemer, Switzerland. Methods: Comparative and prospective study of 120 eyes from 60 patients. Several recommended measurements were taken with the optical biometers LenstarLS 900 (Haag Streit AG and with Pentacam y Galilei topographers. The results were evaluated using the linear regresión analysis and Pearson´s correlation. Results: There is high correlation among the central corneal thickness measurements taken by the Lenstar equipment and topographers Pentacam and Galilei. Conclusion: The new biometer LENSTAR provided results that correlated very well with those of the Pentacam and Galilei systems. The Lenstar is a precise device that will be helpful for any cataract or refractive surgery.

  2. The Galileo Teacher Training Program Global Efforts

    Science.gov (United States)

    Doran, R.; Pennypacker, C.; Ferlet, R.

    2012-08-01

    The Galileo Teacher Training Program (GTTP) successfully named representatives in nearly 100 nations in 2009, the International Year of Astronomy (IYA2009). The challenge had just begun. The steps ahead are how to reach educators that might benefit from our program and how to help build a more fair and science literate society, a society in which good tools and resources for science education are not the privilege of a few. From 2010 on our efforts have been to strengthen the newly formed network and learn how to equally help educators and students around the globe. New partnerships with other strong programs and institutions are being formed, sponsorship schemes being outlined, new tools and resources being publicized, and on-site and video conference training conducted all over the world. Efforts to officially accredit a GTTP curriculum are on the march and a stronger certification process being outlined. New science topics are being integrated in our effort and we now seek to discuss the path ahead with experts in this field and the community of users, opening the network to all corners of our beautiful blue dot. The main aim of this article is to open the discussion regarding the urgent issue of how to reawaken student interest in science, how to solve the gender inequality in science careers, and how to reach the underprivileged students and open to them the same possibilities. Efforts are in strengthening the newly formed network and learning how to equally help educators and students around the globe.

  3. Galileo and 400 Years of Telescopic Astronomy

    CERN Document Server

    Grego, Peter

    2010-01-01

    Imagine yourself living 400 years ago, right before the telescope was first used by Galileo to look up into the skies and find unforeseen wonders. You probably believed, with most of the known world, that Earth was at the center of the magnificent parade of planets and stars above you, and the Sun’s purpose in journeying across the sky was to give Earth daylight and warmth. Suddenly, though, your world is turned upside down. The Church, all powerful in its doctrines and teachings of the times, continues to support theories that don’t fit the facts presented by scientists. Scientists in their quest for truth must hide their findings or risk the harsh penalties imposed by the Church. We have gone from a comforting Earth-centered universe to a tiny floating spec in a gigantic cosmos, barely a comma in a lengthy treatise. And we have gone there in a blink of an eye. We may have lost our central position in the universe, but Grego and Mannion show us how much we have gained in understanding the universe around...

  4. IDA 'Galileo Award' presented to Bob Mizon

    Science.gov (United States)

    Miles, R.

    2006-12-01

    The Galileo Award is given once per year by the European Region of the International Dark-Sky Association (IDA) for outstanding achievements in combating light pollution in Europe. I am pleased to report that the 2006 award has been made to our very own Bob Mizon, Coordinator of the BAA Campaign for Dark Skies (CfDS). As most of you will know, the CfDS was set up by concerned members of the BAA in 1989 to counter the ever-growing tide of skyglow which has tainted the night sky over Britain since the 1950s, and to address the related problems of light trespass and energy wastage. Bob has been doing an outstanding job as Coordinator of the CfDS for many years and so it was a real pleasure for me not only to attend the 6th European Dark-Skies Symposium in Portsmouth (of which Bob was one of the organisers) but also to be present when Bob received his much-deserved award from Bob Gent, Vice-President of the Board of Directors of the IDA.

  5. Galileo Observations of Gaspra, Ida, and Dactyl: Implications for Meteoritics

    Science.gov (United States)

    Chapman, C. R.

    1995-09-01

    Galileo opportunisitically encountered the S-type asteroids Gaspra and Ida, and discovered Ida's satellite Dactyl. Returned data include high-resolution multi-color images and regional infrared reflectance spectra. Preliminary analyses [1-4] are supplemented by special issues of Icarus (Jan. 1994 and in press). Derived information includes shape, photometry, spectrophotometry, surface morphology, and crater statistics. This is an enormous leap; asteroids were previously studied telescopically with little spatial resolution. Rendezvous missions (like NEAR, February 1996 launch) can obtain masses and high-resolution, uniform, global data (including x-ray and gamma-ray). Nevertheless, we have learned much about the relationships between asteroids and meteorites. Surface geology and body shapes only hint at interior structure. Despite a dumb-bell aspect from some directions, much of Gaspra's shape is bounded by planes suggesting a monolithic interior. Ida more clearly has two lobes; its interior is rubblized to an unknown degree. Recent modelling of asteroidal fragmentation processes, studies of double craters, and observations of other asteroids imply that many smaller asteroids may be multi-component rubble piles. Asteroidal regolith processes differ from those on the Moon. Cratering ejecta are widespread (e.g. by Ida's large, fresh crater Azzurra) and much ejecta escapes a small asteroid entirely. Downslope movement of regolith is evident on both Gaspra and Ida. Ida's regolith may be tens of meters deep; it must be relatively immature, grading downward into coarser material (megaregolith or rubble-pile structure). Craters show a "steep" production population for Gaspra (i.e. dominated by small impactors). Larger craters do not saturate, so Gaspra's surface was re-set comparatively recently or Gaspra may be made of metallic-strength material. Ida is (nearly) saturated by craters; it could have been struck by the same population that struck Gaspra and the post

  6. Jupiter small satellite montage

    Science.gov (United States)

    2000-01-01

    A montage of images of the small inner moons of Jupiter from the camera onboard NASA's Galileo spacecraft shows the best views obtained of these moons during Galileo's 11th orbit around the giant planet in November 1997. At that point, Galileo was completing its first two years in Jupiter orbit--known as the Galileo 'prime mission'--and was about to embark on a successful two-year extension, called the Galileo Europa Mission. The top two images show the moon Thebe. Thebe rotates by approximately 50 degrees between the time these two images were taken, so that the same prominent impact crater is seen in both views; this crater, which has been given the provisional name Zethus, is near the point on Thebe that faces permanently away from Jupiter. The next two images show the moon Amalthea; they were taken with the Sun directly behind the observer, an alignment that emphasizes patterns of intrinsically bright or dark surface material. The third image from the top is a view of Amalthea's leading side, the side of the moon that 'leads' as Amalthea moves in its orbit around Jupiter. This image looks 'noisy' because it was obtained serendipitously during an observation of the Jovian satellite Io (Amalthea and Io shared the same camera frame but the image was exposed for bright Io rather than for the much darker Amalthea). The fourth image from the top emphasizes prominent 'spots' of relatively bright material that are located near the point on Amalthea that faces permanently away from Jupiter. The bottom image is a view of the tiny moon Metis. In all the images, north is approximately up, and the moons are shown in their correct relative sizes. The images are, from top to bottom: Thebe taken on November 7, 1997 at a range of 504,000 kilometers (about 313,000 miles); Thebe on November 7, 1997 at a range of 548,000 kilometers (about 340,000 miles); Amalthea on November 6, 1997 at a range of about 650,000 kilometers (about 404,000 miles); Amalthea on November 7, 1997 at a

  7. Detecting 3D vegetation structure with the Galileo space probe: Can a distant probe detect vegetation structure on Earth?

    CERN Document Server

    Doughty, Christopher E

    2016-01-01

    Sagan et al. (1993) used the Galileo space probe data and first principles to find evidence of life on Earth. Here we ask whether Sagan et al. (1993) could also have detected whether life on Earth had three-dimensional structure, based on the Galileo space probe data. We reanalyse the data from this probe to see if structured vegetation could have been detected in regions with abundant photosynthetic pigments through the anisotropy of reflected shortwave radiation. We compare changing brightness of the Amazon forest (a region where Sagan et al. (1993) noted a red edge in the reflectance spectrum, indicative of photosynthesis) as the planet rotates to a common model of reflectance anisotropy and found measured increase of surface reflectance of 0.019 versus a 0.007 predicted from only anisotropic effects. We hypothesize the difference was due to minor cloud contamination. However, the Galileo dataset had only a small change in phase angle (sun-satellite position) which reduced the observed anisotropy signal an...

  8. The Galileo PPS expert monitoring and diagnostic prototype

    Science.gov (United States)

    Bahrami, Khosrow

    1989-01-01

    The Galileo PPS Expert Monitoring Module (EMM) is a prototype system implemented on the SUN workstation that will demonstrate a knowledge-based approach to monitoring and diagnosis for the Galileo spacecraft Power/Pyro subsystems. The prototype will simulate an analysis module functioning within the SFOC Engineering Analysis Subsystem Environment (EASE). This document describes the implementation of a prototype EMM for the Galileo spacecraft Power Pyro Subsystem. Section 2 of this document provides an overview of the issues in monitoring and diagnosis and comparison between traditional and knowledge-based solutions to this problem. Section 3 describes various tradeoffs which must be considered when designing a knowledge-based approach to monitoring and diagnosis, and section 4 discusses how these issues were resolved in constructing the prototype. Section 5 presents conclusions and recommendations for constructing a full-scale demonstration of the EMM. A Glossary provides definitions of terms used in this text.

  9. Development and Use of the Galileo and Ulysses Power Sources

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, Gary L; Hemler, Richard J; Schock, Alfred

    1994-10-01

    Paper presented at the 45th Congress of the International Astronautical Federation, October 1994. The Galileo mission to Jupiter and the Ulysses mission to explore the polar regions of the Sun required a new power source: the general-purpose heat source radioisotope thermoelectric generator (GPHS-RTG), the most powerful RTG yet flow. Four flight-qualified GPHS-RTGs were fabricated with one that is being used on Ulysses, two that are being used on Galileo and one that was a common spare (and is now available for the Cassini mission to Saturn). In addition, and Engineering Unit and a Qualification Unit were fabricated to qualify the design for space through rigorous ground tests. This paper summarizes the ground testing and performance predictions showing that the GPHS-RTGs have met and will continue to meet or exceed the performance requirements of the ongoing Galileo and Ulysses missions. There are two copies in the file.

  10. Four centuries later: how to close the Galileo case?

    Science.gov (United States)

    Segre, Michael

    The "Galileo case" is still open: John Paul II's 1979 initiative to "recognize wrongs from whatever side they come" was carried out in an unsatisfactory manner. The task would have been easy had the Pontifical Study Commission created for that purpose concentrated on the 1616 decree alone and declared it not in line with the hermeneutical guidelines of the Council of Trent, in agreement with Galileo and not with Saint Robert Bellarmine. A possible avenue to closing the "Galileo case" on the part of the Church of Rome could, thus, be to change its current defensive attitude and declare itself no longer what it was in 1616, since another such "case" is, hopefully, no longer conceivable.

  11. Galileo Avionica's technologies and instruments for planetary exploration.

    Science.gov (United States)

    Battistelli, E; Falciani, P; Magnani, P; Midollini, B; Preti, G; Re, E

    2006-12-01

    Several missions for planetary exploration, including comets and asteroids, are ongoing or planned by the European Space Agencies: Rosetta, Venus Express, Bepi Colombo, Dawn, Aurora and all Mars Programme (in its past and next missions) are good examples. The satisfaction of the scientific request for the mentioned programmes calls for the development of new instruments and facilities devoted to investigate the body (planet, asteroid or comet) both remotely and by in situ measurements. The paper is an overview of some instruments for remote sensing and in situ planetary exploration already developed or under study by Galileo Avionica Space & Electro-Optics B.U. (in the following shortened as Galileo Avionica) for both the Italian Space Agency (ASI) and for the European Space Agency (ESA). Main technologies and specifications are outlined; for more detailed information please refer to Galileo Avionica's web-site at: http://www.galileoavionica.com .

  12. Combined analysis of GNSS and SLR observations for the GIOVE satellites

    Science.gov (United States)

    Thaller, D.; Steinbach, A.; Dach, R.

    2009-04-01

    The GGSP (Galileo Geodetic Service Provider) is responsible to provide the geodetic basement of the future European GNSS, the Galileo system. The AIUB is one partner of the consortium of seven institutions. In the context of this project, the data of 13 GESS (Galileo Experimental Sensor Stations) are processed together with the GPS data of about 120 IGS sites. Apart from the station coordinates also the satellite orbits, ERPs, and clock corrections are computed. Since the 13 GESS do not only provide GPS data but also track the two first Galileo satellites (i.e., GIOVE-A and GIOVE-B), a combined processing of the GPS and Galileo data using microwave data is possible. Due to the sparse network of GESS the GPS data highly support the Galileo related products (the orbits and satellite clock corrections). Nevertheless, the quality of the GIOVE orbits is limited to about 20 cm. As both GIOVE are equipped with retro-reflector arrays, the satellites are tracked by satellite laser ranging (SLR), as it is already done for some GLONASS satellites and those two GPS satellites equipped with retro-reflectors. The availability of SLR data allows a validation of the satellite orbits determined from GNSS observations. The range residuals show whether there is any systematic difference between the GNSS and SLR system and, thus, may help to improve the orbit modeling for the GIOVE satellites. Furthermore, we will include the SLR tracking data into the orbit determination in order to derive a combined GNSS+SLR orbit. It will be studied whether the inclusion of SLR data shows any significant improvement for the combined orbit compared to the GNSS-only orbit. This study can be seen as a further step toward the combined processing of GNSS and SLR observations for a fully integrated multi-technique data analysis.

  13. Galileo Safety-of-Life Service Utilization for Railway Non-Safety and Safety Critical Applications

    Science.gov (United States)

    Mocek, Hynek; Filip, Aleš; Bazant, Lubor

    Global Navigation Satellite System (GNSS) Galileo is expected to play an essential role in railway transport with view to reduce operational, investment and maintenance costs. However, quality requirements of the GNSS originate mainly from the aviation suggestions. Different safety philosophies used in aviation domain and in railway signaling complicate direct employment of the GNSS quality measures to the railway telematic applications. The objective of this paper is to outline the conception of railway requirements specification for the GNSS in order to cover a large amount of the appropriate applications in the non-safety and safety related domains. The elaborated methodology enables to provide specification of minimal quantitative requirements for GNSS system by means of railway attributes RAMS. This process generally represents contribution for GNSS system certification, when it is necessary to demonstrate that the GNSS system meets requirements, and the system outputs are correct. In the second level, certification of the specific GNSS application must follow subsequently.

  14. Ultraviolet Studies of Jupiter's Hydrocarbons and Aerosols from Galileo

    Science.gov (United States)

    Gladstone, G. Randall

    2001-01-01

    This is the final report for this project. The purpose of this project was to support PI Wayne Pryor's effort to reduce and analyze Galileo UVS (Ultraviolet Spectrometer) data under the JSDAP program. The spectral observations made by the Galileo UVS were to be analyzed to determine mixing ratios for important hydrocarbon species (and aerosols) in Jupiter's stratosphere as a function of location on Jupiter. Much of this work is still ongoing. To date, we have concentrated on analyzing the variability of the auroral emissions rather than the absorption signatures of hydrocarbons, although we have done some work in this area with related HST-STIS data.

  15. Family Portrait of the Small Inner Satellites of Jupiter

    Science.gov (United States)

    1997-01-01

    These images, taken by Galileo's solid state imaging system between November 1996 and June 1997, provide the first ever 'family portrait' of the four small, irregularly shaped moons that orbit Jupiter in the zone between the planet's ring and the larger Galilean satellites. The moons are shown in their correct relative sizes, with north approximately up in all cases. From left to right, arranged in order of increasing distance from Jupiter, are Metis (longest dimension is approximately 60 kilometers or 37 miles across), Adrastea (20 kilometers or 12 miles across), Amalthea (247 kilometers or 154 miles across), and Thebe (116 kilometers or 72 miles across). While Amalthea, the largest of these four tiny moons, was imaged by NASA's two Voyager spacecraft in 1979 with a resolution comparable to what is shown here, the new Galileo observations represent the first time that Metis, Adrastea, and Thebe have been seen as more than points of light.The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/ galileo.

  16. Integrated results from the COPERNICUS and GALILEO studies.

    Science.gov (United States)

    Pielen, Amelie; Clark, W Lloyd; Boyer, David S; Ogura, Yuichiro; Holz, Frank G; Korobelnik, Jean-Francois; Stemper, Brigitte; Asmus, Friedrich; Rittenhouse, Kay D; Ahlers, Christiane; Vitti, Robert; Saroj, Namrata; Zeitz, Oliver; Haller, Julia A

    2017-01-01

    To report on the efficacy and safety of intravitreal aflibercept in patients with macular edema secondary to central retinal vein occlusion (CRVO) in an integrated analysis of COPERNICUS and GALILEO. Patients were randomized to receive intravitreal aflibercept 2 mg every 4 weeks or sham injections until week 24. From week 24 to week 52, all intravitreal aflibercept-treated patients in both studies and sham-treated patients in COPERNICUS were eligible to receive intravitreal aflibercept based on prespecified criteria. In GALILEO, sham-treated patients continued to receive sham treatment through week 52. At week 24, mean gain in best-corrected visual acuity and mean reduction in central retinal thickness were greater for intravitreal aflibercept-treated patients compared with sham, consistent with individual trial results. At week 52, after 6 months of intravitreal aflibercept as-needed treatment in COPERNICUS, patients originally randomized to sham group experienced visual and anatomic improvements but did not improve to the extent of those initially treated with intravitreal aflibercept, while the sham group in GALILEO did not improve over week 24 mean best-corrected visual acuity scores. Ocular serious adverse events occurred in COPERNICUS and GALILEO confirmed that intravitreal aflibercept is an effective treatment for macular edema following CRVO.

  17. Galileo ootab eestlaste osavõttu / Marko Saaret

    Index Scriptorium Estoniae

    Saaret, Marko

    2003-01-01

    Euroopa Liit käivitas eelmisel aastal uuesti mitu miljardit krooni maksva iseseisva satelliitnavigatsiooni süsteemi väljatöötamise, milles võivad osaleda ka kandidaatriikide ettevõtjad. Kommenteerib AS-i Regio juht Teet Jagomägi, kelle hinnangul ei võimalda Eesti tehnoloogiaettevõtete tase Galileo ehitamises osaleda.

  18. Galileo and the Pendulum: Latching on to Time

    Science.gov (United States)

    Machamer, Peter; Hepburn, Brian

    2004-01-01

    Galileo changed the very concepts or categories by which natural philosophy could deal with matter and motion. Central to these changes was his introduction of time as a fundamental concept. He worked with the pendulum and with the inclined plane to discover his new concept of motion. Both of these showed him that acceleration and time were…

  19. [In 2009, International Year of Astronomy: Galileo, Mutis and Duperier].

    Science.gov (United States)

    González de Posada, Francisco

    2009-01-01

    In commemoration of International Year of Astronomy (2009, proclaimed by the United Nations (UN) 62nd General Assembly) Galileo's revolutions, named, respectively, astronomic, philosophical, mathematical and theological are considered first. And complementarily the Spanish contributions of the doctor Jose Celestino Mutis and Arturo Duperier to the astrophysics are remembered, in their respective anniversary.

  20. Galileo's Finger - The Ten Great Ideas of Science

    Science.gov (United States)

    Atkins, Peter

    2003-06-01

    Why Galileo's finger? Galileo, one of whose fingers is preserved in a vessel displayed in Florence, provided much of the impetus for modern science, pointing the way out of medieval ignorance. In this brilliant account of the central ideas of contemporary science, Peter Atkins celebrates the effectiveness of Galileo's symbolic finger for revealing the nature of our universe, our world, and ourselves. Galileo's Finger takes the reader on an extraordinary journey that embraces the ten central ideas of current science. "By a great idea," writes Peter Atkins, "I mean a simple concept of great reach, an acorn of an idea that ramifies into a great oak tree of application, a spider of an idea that can spin a great web and draw in a feast of explanation and elucidation." With wit, charm, and patience, Atkins leads the reader to an understanding of the essence of the whole of science, from evolution and the emergence of complexity, to entropy, the spring of all change in the universe; from energy, the universalization of accountancy, to symmetry, the quantification of beauty; and from cosmology, the globalization of reality, to spacetime, the arena of all action. "My intention is for us to travel to the high ridges of science," Atkins tells us. "As the journey progresses and I lead you carefully to the summit of understanding, you will experience the deep joy of illumination that science alone provides." Galileo's Finger breaks new ground in communicating science to the general reader. Here are the essential ideas of today's science, explained in magical prose.

  1. Galileo OS SIS ICD导航电文设计解析%Navigation Message Designing in Galileo OS SIS ICD

    Institute of Scientific and Technical Information of China (English)

    李作虎; 郝金明; 李建文; 吕志伟

    2011-01-01

    The first official release of an updated “Galileo ()pen Service Signal-In-Space Interface Control Document” (Galileo OS SIS ICD) from European Union on April 13 meant great progress of Galileo establishment from concept designing to orbit test and to system construction, which would be of great significance for the development of GNSS. Compared to GPS Interface Specification Document on LI C/A code, the ideas and characteristics in the designing on message structure and contents from Galileo OS SIS ICD were analyzed. The analysis showed that the message designing of Galileo OS not only took over the designing partly from GPS but also acquired innovation. The overall designing is open and flexible, specially, such aspects as the flow of pages, the diversity of almanac source, compatibility and interoperability, and integrity represent the development of GNSS as well as the advancement of designing ideas of GNSS. The ideas of Galileo message designing will be helpful not only for guidance to the designing of Beidou navigation message but also for the study on the interoperation between our GNSS and Galileo.%欧盟在2010-04-13首次正式发布了Galileo公开服务空间信号接口控制文档(Galileo OS SIS ICD),标志着Galileo系统建设从概念设计、在轨验证到系统实施又迈进了重要一步,对全球导航卫星系统(GNSS)的发展具有重要意义.通过与GPS接口说明文档比较,解析了Galileo OS SIS ICD中导航电文结构设计和内容设计方面的思路和特点.解析表明,与GPS L1 C/A码导航电文设计相比,Galileo OS在导航电文设计上既有继承、亦有创新.整体设计体现了开放和灵活的特点,特别是在电文页流结构、电文星间交叉播发、兼容和互操作以及完好性方面的设计既体现了GNSS技术的发展,又体现了GNSS设计理念的进步.Galileo导航电文的设计理念不仅可为我国北斗卫星导航系统电文的设计提供参考,而且有利于加强

  2. Galileo IOV Electrical Power Subsystem Relies On Li-Ion Batter Charge Management Controlled By Hardware

    Science.gov (United States)

    Douay, N.

    2011-10-01

    In the frame of GALILEO In-Orbit Validation program which is composed of 4 satellites, Thales Alenia Space France has designed, developed and tested the Electrical Power Subsystem. Besides some classical design choices like: -50V regulated main power bus provided by the PCDU manufactured by Terma (DK), -Solar array, manufactured by Dutch-Space (NL), using Ga-As triple junction technology from Azur Space Power Solar GmbH, -SAFT (FR) Lithium-ion Battery for which cell package balancing function is required, -Solar Array Drive Mechanism, provided by RUAG Space Switzerland, to transfer the power. This subsystem features a fully autonomous, failure tolerant, battery charge management able to operate even after a complete unavailability of the on-board software. The battery charge management is implemented such that priority is always given to satisfy the satellite main bus needs in order to maintain the main bus regulation under MEA control. This battery charge management principle provides very high reliability and operational robustness. So, the paper describes : -the battery charge management concept using a combination of PCDU hardware and relevant battery lines monitoring, -the functional aspect of the single point failure free S4R (Sequential Switching Shunt Switch Regulator) and associated performances, -the failure modes isolated and passivated by this architecture. The paper will address as well the autonomous balancing function characteristics and performances.

  3. A new FOA estimation method in SAR/GALILEO system

    Science.gov (United States)

    Liu, Gang; He, Bing; Li, Jilin

    2007-11-01

    The European Galileo Plan will include the Search and Rescue (SAR) transponder which will become part of the future MEOSAR (Medium earth orbit Search and Rescue) system, the new SAR system can improve localization accuracy through measuring the frequency of arrival (FOA) and time of arrival (TOA) of beacons, the FOA estimation is one of the most important part. In this paper, we aim to find a good FOA algorithm with minimal estimation error, which must be less than 0.1Hz. We propose a new method called Kay algorithm for the SAR/GALILEO system by comparing some frequency estimation methods and current methods using in the COAPAS-SARSAT system and analyzing distress beacon in terms of signal structure, spectrum characteristic. The simulation proves that the Kay method for FOA estimation is better.

  4. Galileo's Discorsi as a Tool for the Analytical Art.

    Science.gov (United States)

    Raphael, Renee Jennifer

    2015-01-01

    A heretofore overlooked response to Galileo's 1638 Discorsi is described by examining two extant copies of the text (one which has received little attention in the historiography, the other apparently unknown) which are heavily annotated. It is first demonstrated that these copies contain annotations made by Seth Ward and Sir Christopher Wren. This article then examines one feature of Ward's and Wren's responses to the Discorsi, namely their decision to re-write several of Galileo's geometrical demonstrations into the language of symbolic algebra. It is argued that this type of active reading of period mathematical texts may have been part of the regular scholarly and pedagogical practices of early modern British mathematicians like Ward and Wren. A set of Appendices contains a transcription and translation of the analytical solutions found in these annotated copies.

  5. Computer memory power control for the Galileo spacecraft

    Science.gov (United States)

    Detwiler, R. C.

    1983-01-01

    The developmental history, major design drives, and final topology of the computer memory power system on the Galileo spacecraft are described. A unique method of generating memory backup power directly from the fault current drawn during a spacecraft power overload or fault condition allows this system to provide continuous memory power. This concept provides a unique solution to the problem of volatile memory loss without the use of a battery of other large energy storage elements usually associated with uninterrupted power supply designs.

  6. A post-Galileo view of Io's interior

    Science.gov (United States)

    Keszthelyi, L.; Jaeger, W.L.; Turtle, E.P.; Milazzo, M.; Radebaugh, J.

    2004-01-01

    We present a self-consistent model for the interior of Io, taking the recent Galileo data into account. In this model, Io has a completely molten core, substantially molten mantle, and a very cold lithosphere. Heat from magmatic activity can mobilize volatile compounds such as SO2 in the lithosphere, and the movement of such cryogenic fluids may be important in the formation of surface features including sapping scarps and paterae. ?? Published by Elsevier Inc.

  7. Galileo SSI Observations of Volcanic Activity at Tvashtar Catena, Io

    Science.gov (United States)

    Milazzo, M. P.; Keszthely, L. P.; Radebaugh, J.; Davies, A. G.; Turtle, E. P.; Geissler, P.; Klaasen, K. P.; McEwen, A. S.

    2005-01-01

    Introduction: We report on the analysis of the Galileo SSI's observations of the volcanic activity at Tvashtar Catena, Io as discussed by Milazzo et al. Galileo's Solid State Imager (SSI) observed Tvashtar Catena (63 deg N, 120 deg W) four times between November 1999 and October 2001, providing a unique look at the distinctive high latitude volcanism on Io. The November 1999 observation spatially resolved, for the first time, an active extraterrestrial fissure eruption. The brightness temperature of the lavas at the November 1999 fissure eruption was 1300 K. The second observation (orbit I27, February 2000) showed a large (approx. 500 sq km) region with many, small spots of hot, active lava. The third observation was taken in conjunction with a Cassini observation in December 2000 and showed a Pele-like plume deposition ring, while the Cassini images revealed a 400 km high Pele-type plume above the Catena. The final Galileo SSI observation of Tvashtar was acquired in October 2001, and all obvious (to SSI) activity had ceased, although data from Galileo's Near Infrared Mapping Spectrometer (NIMS) indicated that there was still significant thermal emission from the Tvashtar region. We have concentrated on analyzing the style of eruption during orbit I27 (February 2000). Comparison with a lava flow cooling model indicates that the behavior of the Tvashtar eruption during I27 does not match that of "simple" advancing lava flows. Instead, it may be an active lava lake or a complex set of lava flows with episodic, overlapping (in time and space) eruptions.

  8. Curbing "Math Anxiety" with Galileo While Teaching Physicists, too

    Science.gov (United States)

    Schwartz, Brian P.

    2006-12-01

    Carthage College's introductory physics course caters to both freshmen in our program and students in general education. While "Understandings of Physics" is a conceptual overview of our discipline, physical science is necessarily quantitative. Galileo's "Dialogue Concerning the Two New Sciences" provides us with a novel way to teach the fundamentals of motion both to students who "fear" mathematics, as well as those who are adept at solving algebraic equations.

  9. "Life of Galileo" Théâtre de Carouge

    CERN Multimedia

    2008-01-01

    Special offer for CERN personnel CERN personnel and their spouses have until Tuesday, 18 March 2008 to buy tickets for « Vie de Galilée » ("Life of Galileo") at the Théâtre de Carouge at the special discount rate of 28 CHF (instead of 35 CHF). This play, by the German dramatist Bertolt Brecht, is directed by Manfred Karge and recounts the life of the father of modern physics in fifteen tableaux. The wily, impassioned teacher Galileo is about to substantiate Copernicus’ theory that the Earth is not a static object but revolves around the sun, a discovery that revolutionised mankind’s view of itself and the world. When hauled before the Inquisition, he recants. "Life of Galileo" is the first major dramatic work after the invention of the atom bomb to address the issues of freedom of thought and ethics in the context of scientific discoveries. Special performances on 3, 10, 15 and 22 April will be followed by organised debat...

  10. Assessment of Galileo modal test results for mathematical model verification

    Science.gov (United States)

    Trubert, M.

    1984-01-01

    The modal test program for the Galileo Spacecraft was completed at the Jet Propulsion Laboratory in the summer of 1983. The multiple sine dwell method was used for the baseline test. The Galileo Spacecraft is a rather complex 2433 kg structure made of a central core on which seven major appendages representing 30 percent of the total mass are attached, resulting in a high modal density structure. The test revealed a strong nonlinearity in several major modes. This nonlinearity discovered in the course of the test necessitated running additional tests at the unusually high response levels of up to about 21 g. The high levels of response were required to obtain a model verification valid at the level of loads for which the spacecraft was designed. Because of the high modal density and the nonlinearity, correlation between the dynamic mathematical model and the test results becomes a difficult task. Significant changes in the pre-test analytical model are necessary to establish confidence in the upgraded analytical model used for the final load verification. This verification, using a test verified model, is required by NASA to fly the Galileo Spacecraft on the Shuttle/Centaur launch vehicle in 1986.

  11. Dust en-route to Jupiter and the Galilean satellites

    CERN Document Server

    Krüger, H; Krueger, Harald; Gruen, Eberhard

    2002-01-01

    Spacecraft investigations during the last ten years have vastly improved our knowledge about dust in the Jovian system. All Galilean satellites, and probably all smaller satellites as well, are sources of dust in the Jovian system. In-situ measurements with the dust detectors on board the Ulysses and Galileo spacecraft have for the first time demonstrated the electromagnetic interaction of charged dust grains with the interplanetary magnetic field and with a planetary magnetosphere. Jupiter's magnetosphere acts as a giant mass-velocity spectrometer for charged 10-nanometer dust grains. These dust grains are released from Jupiter's moon Io with typical rate of 1 kg s^1. The dust streams probe the plasma conditions in the Io plasma torus and can be used as a potential monitor of Io's volcanic plume activity. The other Galilean satellites are surrounded by tenuous impact-generated clouds of mostly sub-micrometer ejecta grains. Galileo measurements have demonstrated that impact-ejecta derived from hypervelocity i...

  12. GALILEO/SINS组合导航系统研究%Research on GALILEO/SINS Integrated Navigation System

    Institute of Scientific and Technical Information of China (English)

    华冰; 刘建业; 熊智; 刘红

    2005-01-01

    GALILEO是新一代的全球卫星定位系统.文章根据GALILEO系统的特点,有针对性地研究了GALILEO/捷联惯导(SINS)伪距组合导航模式.分析并建立了GALILEO的误差方程,并以此为基础,给出了GALILEO/SINS伪距组合导航系统的误差模型和相应的卡尔曼滤波方程.为了有效验证设计的组合导航系统的有效性,在仿真过程中采用了协方差分析法,对组合导航系统性能进行了仿真研究.仿真结果表明GALILEO/SINS伪距组合导航系统能够有效的提高导航精度,随着GALILEO的不断完善,该系统将具有很大的应用前景.

  13. Thermal Emission Variability of Zamama, Culann and Tupan on Io Using Galileo Near-Infrared Mapping Spectrometer (NIMS) Data

    Science.gov (United States)

    Ennis, M. E.; Davies, A. G.

    2005-01-01

    The Jovian satellite Io is the most volcanically active body in the Solar System. Previous analyses [e.g., 1-4] indicate the presence of high-temperature silicate volcanism on Io, similar to silicate volcanism occurring on Earth. Instruments onboard the Galileo spacecraft, especially the Near Infrared Mapping Spectrometer (NIMS) and the Solid State Imager (SSI), provided much data of Io s active volcanoes throughout the duration of the Galileo mission (June 1996-September 2003). NIMS data is particularly sensitive to thermal emission from active and cooling lava over cooling times of seconds to a few years. The objective of this ongoing study of Io s volcanism is to determine the variability of thermal emission from volcanoes on Io s surface, in order to better understand the styles of eruption, and to constrain the volumes of material erupted. Ultimately, this will help to constrain the contribution of active volcanism to Io s thermal budget. Data have been analyzed for the volcano Zamama, located at 173 W, 21 N, and the power output of Zamama, the volumes of lava being erupted, and the eruption rate determined. Culann and Tupan have also been analysed in this way. This abstract primarily concentrates on Zamama.

  14. Thermal Conductivity Measurements on Icy Satellite Analogs

    Science.gov (United States)

    Javeed, Aurya; Barmatz, Martin; Zhong, Fang; Choukroun, Mathieu

    2012-01-01

    With regard to planetary science, NASA aspires to: "Advance scientific knowledge of the origin and history of the solar system, the potential for life elsewhere, and the hazards and resources present as humans explore space". In pursuit of such an end, the Galileo and Cassini missions garnered spectral data of icy satellite surfaces implicative of the satellites' structure and material composition. The potential for geophysical modeling afforded by this information, coupled with the plausibility of life on icy satellites, has pushed Jupiter's Europa along with Saturn's Enceladus and Titan toward the fore of NASA's planetary focus. Understanding the evolution of, and the present processes at work on, the aforementioned satellites falls squarely in-line with NASA's cited goal.

  15. Survey of Galileo Plasma Observations in Jupiter's Plasma Sheet

    Science.gov (United States)

    Bagenal, Fran; Wilson, Robert J.; Siler, Scott; Paterson, William R.; Kurth, William S.

    2016-01-01

    The plasma science (PLS) Instrument on the Galileo spacecraft (orbiting Jupiter from December 1995 to September 2003) measured properties of the ions that were trapped in the magnetic field. The PLS data provide a survey of the plasma properties between approx. 5 and 30 Jupiter radii [R(sub J)] in the equatorial region. We present plasma properties derived via two analysis methods: numerical moments and forward modeling. We find that the density decreases with radial distance by nearly 5 orders of magnitude from approx. 2 to 3000 cm(exp.-3) at 6R(sub j) to approx. 0.05cm(sub -3) at 30 R(sub j). The density profile did not show major changes from orbit to orbit, suggesting that the plasma production and transport remained constant within about a factor of 2. The radial profile of ion temperature increased with distance which implied that contrary to the concept of adiabatic cooling on expansion, the plasma heats up as it expands out from Io's orbit (where TI is approx.60-80 eV) at approx. 6R(sub j) to a few keV at 30R(sub j).There does not seem to be a long-term, systematic variation in ion temperature with either local time or longitude. This latter finding differs from earlier analysis of Galileo PLS data from a selection of orbits. Further examination of all data from all Galileo orbits suggests that System Ill variations are transitory on timescales of weeks, consistent with the modeling of Cassini Ultraviolet Imaging Spectrograph observations. The plasma flow is dominated by azimuthal flow that is between 80% and 100% of corotation out to 25 R(sub j).

  16. Studying Galileo at Secondary School: A Reconstruction of His "Jumping-Hill" Experiment and the Process of Discovery.

    Science.gov (United States)

    Teichmann, Jurgen

    1999-01-01

    Finds that interpretation of Galileo's only known experimental manuscript produces some interesting questions that offer pedagogical applications. Promotes classroom "research games" consisting of reconstructed experiments with Galileo's inclined plane and with other instruments to allow further speculation. (Author/WRM)

  17. Great experiments in physics firsthand accounts from Galileo to Einstein

    CERN Document Server

    1959-01-01

    From Galileo's famous experiments in accelerated motion to Einstein's revolutionary theory of relativity, the experiments recorded here trace the evolution of modern physics from its beginnings to the mid-20th century. Brought together for the first time in one volume are important source readings on 25 epochal discoveries that changed man's understanding of the physical world. The accounts, written by the physicists who made them, include:Issac Newton: The Laws of MotionHenry Cavendish: The Law of GravitationAugustin Fresnel: The Diffraction of LightHans Christian Oersted: ElecromagnetismH

  18. Bruno, Galileo, Einstein: The Value of Myths in Physics

    Science.gov (United States)

    Martinez, Alberto

    2015-03-01

    Usually, historical myths are portrayed as something to be avoided in a physics classroom. Instead, I will discuss the positive function of myths and how they can be used to improve physics education. First, on the basis of historical research from primary sources and significant new findings about the Catholic Inquisition, I will discuss how to use the inspirational story of Giordano Bruno when discussing cosmology. Next, I will discuss the recurring story about Galileo and the Leaning Tower of Pisa. Finally, I will discuss how neglected stories about the young Albert Einstein can help to inspire students.

  19. The breakdown of Galileo's Roman network: Crisis and community, ca. 1633.

    Science.gov (United States)

    Findlen, Paula; Marcus, Hannah

    2016-12-01

    Rome has long been central to the story of Galileo's life and scientific work. Through an analysis of the metadata of Galileo's surviving letters, combined with a close reading of the letters themselves, we discuss how Galileo used correspondence to build a Roman network. Galileo initially assembled this network around the members of the Lincean Academy, a few carefully nurtured relationships with important ecclesiastics, and the expertise of well positioned Tuscan diplomats in the Eternal City. However, an analysis of Galileo's correspondence in the aftermath of the trial of 1633 provides us with a unique opportunity to interrogate how his altered circumstances transformed his social relations. Forced to confront the limitations on his activities imposed by Catholic censure and house arrest, Galileo experienced the effects of these restrictions in his relationships with others and especially in his plans for publication. In the years following 1633, Galileo turned his epistolary attention north to the Veneto and to Paris in order to publish his Two New Sciences. While Galileo's Lincean network and papal contacts in Rome were defunct after 1633, we see how Rome remained important to him as the site of a number of Roman disciples who would continue his intellectual project long after his own death.

  20. Learning from the Starry Message: Using Galileo's "Sidereus Nuncius" in Introductory Astronomy Classes

    Science.gov (United States)

    Wiesner, Matthew P.

    2015-01-01

    Every introductory astronomy class encounters Galileo during the course as the first man to systematically study the sky with a telescope. Every Astronomy 101 student meets Galileo as one of the major catalysts behind the shift from the Ptolemaic to the Copernican system and as one of the great minds behind the scientific method. But most of the…

  1. Galileo Infrared Observations of the Shoemaker-Levy 9 G Impact Fireball: A Preliminary Report

    Science.gov (United States)

    Carlson, R. W.; Weissman, P. R.; Segura, M.; Hui, J.; Smythe, W. D.; Johnson, T.; Baines, K. H.; Drossart, P.; Encrenaz, T.; Leader, F. E.; Team, NIMS Science

    1995-01-01

    The Galileo spacecraft was fortuitously situated for a direct view of the impacts of the fragments of comet Shoemaker-Levy 9 in Jupiter's atmosphere. The Galileo Near Infrared Mapping Spectrometer instrument observed several of the impact events in several discrete bands and with a temporal resolution of roughly five seconds. This report provides a preliminary description of the fireball phase.

  2. Learning from the Starry Message: Using Galileo's "Sidereus Nuncius" in Introductory Astronomy Classes

    Science.gov (United States)

    Wiesner, Matthew P.

    2015-01-01

    Every introductory astronomy class encounters Galileo during the course as the first man to systematically study the sky with a telescope. Every Astronomy 101 student meets Galileo as one of the major catalysts behind the shift from the Ptolemaic to the Copernican system and as one of the great minds behind the scientific method. But most of the…

  3. Galileo SSI Observations of Io During Orbits C30 I33

    Science.gov (United States)

    Keszthelyi, L.; Turtle, E.; McEwen, A.; Simonelli, D.; Geissler, P.; Williams, D.; Milazzo, M.; Radebaugh, J.; Jaeger, W.; Klaasen, K. P.

    2002-01-01

    New Galileo SSI imaging of Io from orbits C30 I33 will be presented. The aging Galileo spacecraft continues to produce spectacular new results, including the tallest volcanic plume yet found on Io. Additional information is contained in the original extended abstract.

  4. On systems having Poincaré and Galileo symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Holland, Peter, E-mail: peter.holland@gtc.ox.ac.uk

    2014-12-15

    Using the wave equation in d≥1 space dimensions it is illustrated how dynamical equations may be simultaneously Poincaré and Galileo covariant with respect to different sets of independent variables. This provides a method to obtain dynamics-dependent representations of the kinematical symmetries. When the field is a displacement function both symmetries have a physical interpretation. For d=1 the Lorentz structure is utilized to reveal hitherto unnoticed features of the non-relativistic Chaplygin gas including a relativistic structure with a limiting case that exhibits the Carroll group, and field-dependent symmetries and associated Noether charges. The Lorentz transformations of the potentials naturally associated with the Chaplygin system are given. These results prompt the search for further symmetries and it is shown that the Chaplygin equations support a nonlinear superposition principle. A known spacetime mixing symmetry is shown to decompose into label-time and superposition symmetries. It is shown that a quantum mechanical system in a stationary state behaves as a Chaplygin gas. The extension to d>1 is used to illustrate how the physical significance of the dual symmetries is contingent on the context by showing that Maxwell’s equations exhibit an exact Galileo covariant formulation where Lorentz and gauge transformations are represented by field-dependent symmetries. A natural conceptual and formal framework is provided by the Lagrangian and Eulerian pictures of continuum mechanics.

  5. AIV Platform for the Galileo Precise Timing Facility

    Science.gov (United States)

    Oving, B. A.; Kroon, E.

    2008-08-01

    The Precise Timing Facility (PTF) is an element of the Galileo Ground Mission Segment (GMS) and is responsible for maintaining and distributing the Galileo System Time (GST). The PTF is based on a set of Caesium clocks and Active Hydrogen Maser clocks, the combination of which should be able to provide the required precision and stability of the GST. As the PTF is a critical element within the GMS, diversity is applied in that two PTFs are made by two different companies. The subject of this paper is the PTF that is being developed by Kayser-Threde. To perform the Assembly, Integration and Verification (AIV) activities of the PTF, a dedicated test platform, PTF-AIVP, is developed by the National Aerospace Laboratory, NLR (the Netherlands) and the Nederlands Meetinstituut (NMi). The PTF-AIVP will be used to measure and analyse the (physical) output of the PTF, so that the stringent precision and stability requirements can be verified. Furthermore, it will simulate other Elements in the GMS that are connected to the PTF.

  6. Experimenting Galileo on Board the International Space Station

    Science.gov (United States)

    Fantinato, Samuele; Pozzobon, Oscar; Sands, Obed S.; Welch, Bryan W.; Clapper, Carolyn J.; Miller, James J.; Gamba, Giovanni; Chiara, Andrea; Montagner, Stefano; Giordano, Pietro; hide

    2016-01-01

    The SCaN Testbed is an advanced integrated communications system and laboratory facility installed on the International Space Station (ISS) in 2012. The testbed incorporates a set of new generation of Software Defined Radio (SDR) technologies intended to allow researchers to develop, test, and demonstrate new communications, networking, and navigation capabilities in the actual environment of space. Qascom, in cooperation with ESA and NASA, is designing a Software Defined Radio GalileoGPS Receiver capable to provide accurate positioning and timing to be installed on the ISS SCaN Testbed. The GalileoGPS waveform will be operated in the JPL SDR that is constituted by several hardware components that can be used for experimentations in L-Band and S-Band. The JPL SDR includes an L-Band Dorne Margolin antenna mounted onto a choke ring. The antenna is connected to a radio front end capable to provide one bit samples for the three GNSS frequencies (L1, L2 and L5) at 38 MHz, exploiting the subharmonic sampling. The baseband processing is then performed by an ATMEL AT697 processor (100 MIPS) and two Virtex 2 FPGAs. The JPL SDR supports the STRS (Space Telecommunications Radio System) that provides common waveform software interfaces, methods of instantiation, operation, and testing among different compliant hardware and software products. The standard foresees the development of applications that are modular, portable, reconfigurable, and reusable. The developed waveform uses the STRS infrastructure-provided application program interfaces (APIs) and services to load, verify, execute, change parameters, terminate, or unload an application. The project is divided in three main phases. 1)Design and Development of the GalileoGPS waveform for the SCaN Testbed starting from Qascom existing GNSS SDR receiver. The baseline design is limited to the implementation of the single frequency Galileo and GPS L1E1 receiver even if as part of the activity it will be to assess the

  7. Cibola flight experiment satellite

    Science.gov (United States)

    Davies, P.; Liddle, Doug; Paffett, John; Sweeting, Martin; Curiel, A.; Sun, Wei; Eves, Stuart

    2004-11-01

    In order to achieve an "economy of scale" with respect to payload capacity the major trend in telecommunications satellites is for larger and larger platforms. With these large platforms the level of integration between platform and payload is increasing leading to longer delivery schedules. The typical lifecycle for procurement of these large telecommunications satellites is now 3-6 years depending on the level of non-recurring engineering needed. Surrey Satellite Technology Ltd (SSTL) has designed a low-cost platform aimed at telecommunications and navigation applications. SSTL's Geostationary Minisatellite Platform (GMP) is a new entrant addressing the lower end of the market with payloads up to 250kg requiring less than 1.5 kW power. The British National Space Centre through the MOSAIC Small Satellite Initiative supported the development of GMP. The main design goals for GMP are low-cost for the complete mission including launch and operations and a platform allowing flexible payload accommodation. GMP is specifically designed to allow rapid development and deployment with schedules typically between 1 and 2 years from contract signature to flight readiness. GMP achieves these aims by a modular design where the level of integration between the platform and payload is low. The modular design decomposes the satellite into three major components - the propulsion bay, the avionics bay and the payload module. Both the propulsion and avionics bays are reusable, largely unchanged, and independent of the payload configuration. Such a design means that SSTL or a 3rd party manufacturer can manufacture the payload in parallel to the platform with integration taking place quite late in the schedule. In July 2003 SSTL signed a contract for ESA's first Galileo navigation satellite known as GSTBV2/A. The satellite is based on GMP and ESA plan to launch it into a MEO orbit late in 2005. The second flight of GMP is likely to be in 2006 carrying a geostationary payload

  8. Measurements of ionospheric TEC in the direction of GPS satellites and comparison with three ionospheric models

    Directory of Open Access Journals (Sweden)

    E. Zuccheretti

    1997-06-01

    Full Text Available The IEN Galileo Ferraris uses GPS for time and frequency synchronization. To obtain high performance it is important to reduce the error due to the ionospheric time-delay in GPS measurements. Evaluations of TEC in the direction of GPS satellites, obtained from three different ionospheric models, have been compared with corresponding measurements by GPS signal.

  9. Satellite Communication.

    Science.gov (United States)

    Technology Teacher, 1985

    1985-01-01

    Presents a discussion of communication satellites: explains the principles of satellite communication, describes examples of how governments and industries are currently applying communication satellites, analyzes issues confronting satellite communication, links mathematics and science to the study of satellite communication, and applies…

  10. Competencia intercapitalista en tecnología estratégica y su militarización: el caso del sistema satelital Galileo

    Directory of Open Access Journals (Sweden)

    Gian Carlo Delgado Ramos

    2007-11-01

    Full Text Available Ce sont trois les acteurs qu'on peut identifier dans le développement scientifico-technologique: l'État nation, les sociétés multinationales et les centres de production de connaissances. Leur interaction et synergie pour le développement endogène de technologie civil et militaire sont bien ancrés dans les États capitalistes centraux. Il est possible d'identifier, à partir de cette perspective de synergie que je désigne comme « réseau industriel », une croissante militarisation du « réseau industriel européen » comme le résultat d'une profonde rivalité intercapitaliste (surtout à l'égard des États-Unis. Une évaluation sociologique du rôle des principaux acteurs, ainsi que des conséquences importantes sont présentés de manière générale, pour le cas du secteur militaire et de la défense et, particulièrement, pour le système du satellite Galileo. On examine certaines caractérisques de la compétence entre les systèmes du satellite Galileo (Europe, le GPS (États- Unis, le Glonass (Russie et le Beidou (Chine. De toute façon, nous proposons une discussion sur le rôle à jouer par l'Amérique du Sud, surtout le Brésil, dans le processus de développement de Galileo.

  11. Expected Position Error for an Onboard Satellite GPS Receiver

    Science.gov (United States)

    2015-03-01

    that supports GPS, Galileo, Global’naya Navigatsionnaya Sputnikovaya Sistema (GLONASS), and Quasi-Zenith Satellite System GNSSs. It is designed as a...compared to the main beam half cone angle listed in the GPS Interface Control Document (ICD) [19]. 29 Sidelobes Considered. Power in the sidelobes is...Centered Inertial ENU East-North-Up GDOP Geometric Dilution of Precision GEO Geostationary Orbit GLONASS Global’naya Navigatsionnaya Sputnikovaya Sistema

  12. Refraction effects on the Galileo probe telemetry carrier frequency

    Science.gov (United States)

    Atkinson, D. H.; Spilker, T. R.

    1991-01-01

    As the Galileo probe relay radio link (RRL) signal propagates outward through the Jovian atmosphere, the atmosphere will manifest itself in two ways. First, the geometric path length of the signal is increased, resulting in a small change of the RRL signal departure angle from the proble (transmitter). Secondly, the velocity of the signal is decreased. For a spherical, static atmosphere with a known profile of refractivity versus altitude the effects of refraction on the RRL frequency can be found using a variation of standard ray-tracing techniques, whereby the ray departure angle is found by an iterative process. From the dispersive characteristics of a mixture of hydrogen and helium with trace amounts of methane and ammonia a simple model of the Jovian atmosphere is constructed assuming spherical symmetry and uniform mixing. The contribution to the RRL Doppler frequency arising from refraction is calculated, and its effect on the Doppler wind measurements is discussed.

  13. Friction estimation technique for Galileo scan platform control

    Science.gov (United States)

    Chodas, J. L.

    1982-01-01

    A friction estimation technique has been developed for the scan platform control of the Galileo spacecraft. The purpose of the estimation is to reduce the impact of friction in the scan platform actuator on the pointing performance of the scan platform so that tight pointing requirements can be met. The estimator operates by comparing the actual behavior of the platform with the expected behavior and attributing the difference to the presence of friction. The estimator is coupled with a proportional-integral-derivative controller to generate a control torque for the scan platform actuator. Since the algorithm will be implemented on an onboard digital computer, a stability analysis of the estimator-controller in discrete time is presented. The performance of the design is demonstrated by a sample slew test case.

  14. Selenide isotope generator for the Galileo Mission. Program final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-06-01

    This final report for the Selenide Isotope Generator for the Galileo Mission (SIG/GM) documents the work performed by Teledyne Energy Systems (TES) under US Department of Energy (DOE) Contract No. DE-AC01-78ET33009 (formerly ET-78-C-01-2865) during the period April 10, 1978 to June 30, 1979. Because of technical difficulties with the thermoelectric converter being developed by the 3M Company under separate DOE contract, a Stop Work Order, dated January 29, 1979, was issued by DOE. The TES effort up to the receipt of the Stop Work Order as well as limited technical activities up to the contract conclusion on June 30, 1979 are reported.

  15. Il dito di Galileo le dieci grandi idee della scienza

    CERN Document Server

    Atkins, Peter

    2004-01-01

    Domande e risposte per dieci idee che hanno plasmato il mondo di oggi. Possiamo rintracciare l'origine e il divenire del cosmo? Perché spazio e tempo formano una cosa sola? Che cosa significa l'evoluzione del vivente? Perché il DNA è così importante? Perché il mondo ha bisogno di energia? E com'è che l'aumento dell'entropia scandisce il cambiamento dell'intero universo? Cosa sono gli atomi e cosa c'è di più piccolo di essi? Perché la simmetria della natura e dell'arte cattura il nostro senso della bellezza? Cosa sono quegli elusivi quanti alla base della fisica contemporanea? Siamo sicuri che l'aritmetica non ci inganni? Peter Atkins offre una guida chiara e completa all'impresa scientifica, seguendo la via indicata dal dito di Galileo.

  16. Galileo encounter with 951 Gaspra: First pictures of an asteroid

    Science.gov (United States)

    Belton, M.J.S.; Veverka, J.; Thomas, P.; Helfenstein, P.; Simonelli, D.; Chapman, C.; Davies, M.E.; Greeley, R.; Greenberg, R.; Head, J.; Murchie, S.; Klaasen, K.; Johnson, T.V.; McEwen, A.; Morrison, D.; Neukum, G.; Fanale, F.; Anger, C.; Carr, M.; Pilcher, C.

    1992-01-01

    Galileo images of Gaspra reveal it to be an irregularly shaped object (19 by 12 by 11 kilometers) that appears to have been created by a catastrophic collisional disruption of a precursor parent body. The cratering age of the surface is about 200 million years. Subtle albedo and color variations appear to correlate with morphological features: Brighter materials are associated with craters especially along the crests of ridges, have a stronger 1-micrometer absorption, and may represent freshly excavated mafic materials; darker materials exhibiting a significantly weaker 1-micrometer absorption appear concentrated in interridge areas. One explanation of these patterns is that Gaspra is covered with a thin regolith and that some of this material has migrated downslope in some areas.

  17. Monte Carlo simulations of the Galileo energetic particle detector

    CERN Document Server

    Jun, I; Garrett, H B; McEntire, R W

    2002-01-01

    Monte Carlo radiation transport studies have been performed for the Galileo spacecraft energetic particle detector (EPD) in order to study its response to energetic electrons and protons. Three-dimensional Monte Carlo radiation transport codes, MCNP version 4B (for electrons) and MCNPX version 2.2.3 (for protons), were used throughout the study. The results are presented in the form of 'geometric factors' for the high-energy channels studied in this paper: B1, DC2, and DC3 for electrons and B0, DC0, and DC1 for protons. The geometric factor is the energy-dependent detector response function that relates the incident particle fluxes to instrument count rates. The trend of actual data measured by the EPD was successfully reproduced using the geometric factors obtained in this study.

  18. Orientale and South Pole-Aitken basins on the Moon: Preliminary Galileo imaging results

    Science.gov (United States)

    Head, J.; Fischer, E.; Murchie, S.; Pieters, C.; Plutchak, J.; Sunshine, J.; Belton, M.; Carr, M.; Chapman, C.; Davies, M.

    During the Earth-Moon flyby the Galileo Solid State Imaging System obtained new information on the landscape and physical geology of the Moon. Multicolor Galileo images of the Moon reveal variations in color properties of the lunar surface. Using returned lunar samples as a key, the color differences can be interpreted in terms of variations in the mineral makeup of the lunar rocks and soil. The combined results of Apollo landings and multicolor images from Galileo allow extrapolation of surface composition to areas distant from the landing sites, including the far side invisible from Earth.

  19. Agreement between total corneal astigmatism calculated by vector summation and total corneal astigmatism measured by ray tracing using Galilei double Scheimpflug analyzer.

    Science.gov (United States)

    Feizi, Sepehr; Delfazayebaher, Siamak; Ownagh, Vahid; Sadeghpour, Fatemeh

    2017-08-03

    To evaluate the agreement between total corneal astigmatism calculated by vector summation of anterior and posterior corneal astigmatism (TCAVec) and total corneal astigmatism measured by ray tracing (TCARay). This study enrolled a total of 204 right eyes of 204 normal subjects. The eyes were measured using a Galilei double Scheimpflug analyzer. The measured parameters included simulated keratometric astigmatism using the keratometric index, anterior corneal astigmatism using the corneal refractive index, posterior corneal astigmatism, and TCARay. TCAVec was derived by vector summation of the astigmatism on the anterior and posterior corneal surfaces. The magnitudes and axes of TCAVec and TCARay were compared. The Pearson correlation coefficient and Bland-Altman plots were used to assess the relationship and agreement between TCAVec and TCARay, respectively. The mean TCAVec and TCARay magnitudes were 0.76±0.57D and 1.00±0.78D, respectively (Pvector summation and ray tracing methods cannot be used interchangeably. There was a systematic error between the TCAVec and TCARay magnitudes. Copyright © 2017 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

  20. Euroliidu Galileo süsteem astub kandadele USA GPS-ile / Heiki Suurkask

    Index Scriptorium Estoniae

    Suurkask, Heiki, 1972-

    2005-01-01

    Euroopa Liidu uue navigatsioonisüsteemi Galileo esimene satelliit saadeti eile kosmosesse. Satelliit GIOVE-A kujutab endast esimest ülekandemajakat, millega saab hakata looma kuni 30 satelliidist koosnevat globaalset navigatsioonivõrgustikku

  1. Euroliidu Galileo süsteem astub kandadele USA GPS-ile / Heiki Suurkask

    Index Scriptorium Estoniae

    Suurkask, Heiki, 1972-

    2005-01-01

    Euroopa Liidu uue navigatsioonisüsteemi Galileo esimene satelliit saadeti eile kosmosesse. Satelliit GIOVE-A kujutab endast esimest ülekandemajakat, millega saab hakata looma kuni 30 satelliidist koosnevat globaalset navigatsioonivõrgustikku

  2. Galileo's Double Star: The Experiment That "Proved" the Earth Did Not Move

    CERN Document Server

    Graney, C M

    2006-01-01

    Great opportunities arise for teaching physics, astronomy, and their histories when new discoveries are made that involve concepts accessible to students at every level. Such an opportunity currently exists thanks to the fact that notes written by Galileo indicating that he observed the double star Mizar in the "Big Dipper" have recently come to light. His measurements of this star, given the scientific knowledge at the time, strongly supported the theory that the Earth was fixed in space and not moving. Had Galileo published these results, it is likely that widespread acceptance of the heliocentric theory in scientific circles would have been significantly delayed. In light of these notes, his later reference in his Dialogue to using double stars as a means of proving that the Earth was in motion is puzzling. The physics and mathematics behind Galileo's work is easily within reach of students in introductory physics and astronomy courses, so discussion of Galileo's Mizar work and its interesting implications...

  3. The NASA Galileo Educator Network: Using Astronomy to Engage Teachers in Science Practices

    Science.gov (United States)

    Kruse, B.; Bass, K. M.; Schultz, G.

    2015-11-01

    With funding from a NASA EPOESS grant, the Astronomical Society of the Pacific developed the NASA Galileo Educator Network (GEN), a train-the-trainer teacher professional development program based in part on the Galileo Teacher Training Program. Formal evaluation of the program demonstrates that both teacher trainers and teacher participants grew in their ability to utilize astronomy investigations focusing on science practices as described in the Next Generation Science Standards.

  4. Preface: BeiDou Navigation Satellite System (BDS)/GNSS+: Recent progress and new applications

    Science.gov (United States)

    Jin, Shuanggen

    2017-02-01

    Nowadays, the new China's BeiDou Navigation Satellite System (BDS) has been developed well. At the end of 2016, over 23 BDS satellites were launched, including five geostationary Earth orbit (GEO) satellites, five inclined geosynchronous orbit (IGSO) satellites and nine medium Earth orbit (MEO) satellites. The current BDS service covers China and most Asia-Pacific regions with accuracy of better than 10 m in positioning, 0.2 m/s in velocity and 50 ns in timing. The BDS with global coverage will be completely established by 2020 with five GEO satellites and 30 MEO satellites. The main function of BDS is the positioning, navigation and timing (PNT) as well as short message communications. Together with the United States' GPS, Russia's GLONASS and the European Union's Galileo system as well as other regional augmentation systems, more new applications of multi-Global Navigation Satellite Systems (GNSS) will be exploited and realized in the next decades.

  5. Surface changes on Io during the Galileo mission

    Science.gov (United States)

    Geissler, P.; McEwen, A.; Phillips, C.; Keszthelyi, L.; Spencer, J.

    2004-01-01

    A careful survey of Galileo SSI global monitoring images revealed more than 80 apparent surface changes that took place on Io during the 5 year period of observation, ranging from giant plume deposits to subtle changes in the color or albedo of Patera surfaces. Explosive volcanic activity was discovered at four previously unrecognized centers: an unnamed patera to the south of Karei that produced a Pele-sized red ring, a patera to the west of Zal that produced a small circular bright deposit, a large orange ring detected near the north pole of Io, and a small bright ring near Io's south pole. Only a handful of Io's many active volcanoes produced large scale explosive eruptions, and several of these erupted repeatedly, leaving at least 83% of Io's surface unaltered throughout the Galileo mission. Most of the hot spots detected from SSI, NIMS and ground-based thermal observations caused no noticeable surface changes greater than 10 km in extent over the five year period. Surface changes were found at every location where active plumes were identified, including Acala which was never seen in sunlight and was only detected through auroral emissions during eclipse. Two types of plumes are distinguished on the basis of the size and color of their deposits, confirming post-Voyager suggestions by McEwen and Soderblom [Icarus 55 (1983) 191]. Smaller plumes produce near-circular rings typically 150-200 km in radius that are white or yellow in color unless contaminated with silicates, and frequently coat their surroundings with frosts of fine-grained SO2. The larger plumes are much less numerous, limited to a half dozen examples, and produce oval, orange or red, sulfur-rich rings with maximum radii in the north-south direction that are typically in the range from 500 to 550 km. Both types of plumes can be either episodic or quasi-continuous over a five year period. Repeated eruptions of the smaller SO2-rich plumes likely contribute significantly to Io's resurfacing rate

  6. From Earth to Space: in Celebrating the 400th Anniversary of the Use of Telescope by Galileo to Study the Universe%从仰望星空到走向太空——纪念伽利略用天文望远镜进行天文观测400年

    Institute of Scientific and Technical Information of China (English)

    路甬祥

    2010-01-01

    @@ 2009年是伽利略(Galileo Galilei,1564-1642)首次用望远镜观测天体400周年,因此被联合国确定为国际天文年,以纪念这位人类历史上第一个把望远镜对准茫茫太空的人.伽利略是近代科学的开创者之一,是科学史上的伟人.他把理论与实验相结合,形成了一套基于实验观察、数学分析、严谨实证的科学研究方法,从此人类有了现代意义上的科学.伽利略等人所开创的近现代科学,今天更加充满生机,有力地推动着人类文明的进步与发展.

  7. La nuova costellazione Galileo và in orbita

    Directory of Open Access Journals (Sweden)

    Renzo Carlucci

    2005-12-01

    Full Text Available Siamo arrivati alla fine del 2005 e assistiamo alla partenza del primo satellite del nuovo sistema di posizionamento europeo.Giove-A, nome in codice del primo satellite, non farà parte però della costellazione definitiva, è come un satellite sacrificale che opererà per un certo periodo inviando segnali atti alla messa a punto del sistema finale e da qui a due anni cesserà la sua funzione. Sarà seguito a breve da Giove-B, anch’esso con un destino simile al suo predecessore.

  8. Galileo In-Situ Dust Measurements in Jupiter's Gossamer Rings

    CERN Document Server

    Krueger, Harald; Moissl, Richard; Gruen, Eberhard

    2008-01-01

    During its late orbital mission at Jupiter the Galileo spacecraft made two passages through the giant planet's gossamer ring system. The impact-ionization dust detector on board successfully recorded dust impacts during both ring passages and provided the first in-situ measurements from a dusty planetary ring. In all, a few thousand dust impacts were counted with the instrument accumulators during both ring passages, but only a total of 110 complete data sets of dust impacts were transmitted to Earth. Detected particle sizes range from about 0.2 to 5 micron, extending the known size distribution by an order of magnitude towards smaller particles than previously derived from optical imaging (Showalter et al. 2008). The grain size distribution increases towards smaller particles and shows an excess of these tiny motes in the Amalthea gossamer ring compared to the Thebe ring. The size distribution for the Amalthea ring derived from our in-situ measurements for the small grains agrees very well with the one obtai...

  9. BATMAN: a DMD-based MOS demonstrator on Galileo Telescope

    Science.gov (United States)

    Zamkotsian, Frédéric; Spanò, Paolo; Bon, William; Riva, Marco; Lanzoni, Patrick; Nicastro, Luciano; Molinari, Emilio; Cosentino, Rosario; Ghedina, Adriano; Gonzalez, Manuel; Di Marcantonio, Paolo; Coretti, Igor; Cirami, Roberto; Manetta, Marco; Zerbi, Filippo; Tresoldi, Daniela; Valenziano, Luca

    2012-09-01

    Multi-Object Spectrographs (MOS) are the major instruments for studying primary galaxies and remote and faint objects. Current object selection systems are limited and/or difficult to implement in next generation MOS for space and groundbased telescopes. A promising solution is the use of MOEMS devices such as micromirror arrays which allow the remote control of the multi-slit configuration in real time. We are developing a Digital Micromirror Device (DMD) - based spectrograph demonstrator called BATMAN. We want to access the largest FOV with the highest contrast. The selected component is a DMD chip from Texas Instruments in 2048 x 1080 mirrors format, with a pitch of 13.68μm. Our optical design is an all-reflective spectrograph design with F/4 on the DMD component. This demonstrator permits the study of key parameters such as throughput, contrast and ability to remove unwanted sources in the FOV (background, spoiler sources), PSF effect, new observational modes. This study will be conducted in the visible with possible extension in the IR. A breadboard on an optical bench, ROBIN, has been developed for a preliminary determination of these parameters. The demonstrator on the sky is then of prime importance for characterizing the actual performance of this new family of instruments, as well as investigating the operational procedures on astronomical objects. BATMAN will be placed on the Nasmyth focus of Telescopio Nazionale Galileo (TNG) during next year.

  10. Landform Degradation and Slope Processes on Io: The Galileo View

    Science.gov (United States)

    Moore, Jeffrey M.; Sullivan, Robert J.; Chuang, Frank C.; Head, James W., III; McEwen, Alfred S.; Milazzo, Moses P.; Nixon, Brian E.; Pappalardo, Robert T.; Schenk, Paul M.; Turtle, Elizabeth P.; DeVincenzi, Donald (Technical Monitor)

    2001-01-01

    The Galileo mission has revealed remarkable evidence of mass movement and landform degradation on Io. We recognize four major slope types observed on a number of intermediate resolution (250 m/pixel) images and several additional textures on very high resolution (10 m/pixel) images. Slopes and scarps on Io often show evidence of erosion, seen in the simplest form as alcove-carving slumps and slides at all scales. Many of the mass movement deposits on Io are probably mostly the consequence of block release and brittle slope failure. Sputtering plays no significant role. Sapping as envisioned by McCauley et al. remains viable. We speculate that alcove-lined canyons seen in one observation and lobed deposits seen along the bases of scarps in several locations may reflect the plastic deformation and 'glacial' flow of interstitial volatiles (e.g., SO2) heated by locally high geothermal energy to mobilize the volatile. The appearance of some slopes and near-slope surface textures seen in very high resolution images is consistent with erosion from sublimation-degradation. However, a suitable volatile (e.g., H2S) that can sublimate fast enough to alter Io's youthful surface has not been identified. Disaggregation from chemical decomposition of solid S2O and other polysulfur oxides may conceivably operate on Io. This mechanism could degrade landforms in a manner that resembles degradation from sublimation, and at a rate that can compete with resurfacing.

  11. Galileo infrared imaging spectrometry measurements at the Moon

    Science.gov (United States)

    Mccord, Thomas B.; Soderblom, Larry A.; Carlson, Robert W.; Fanale, Fraser P.; Lopes-Gautier, Rosaly; Ocampo, Adriano; Forsythe, Jennifer; Campbell, Bruce; Granahan, James C.; Smythe, W. D.

    1994-01-01

    Imaging spectrometer observations were made of the surface of the Moon during the December 1990 flyby of the Earth-Moon system by the Galileo spacecraft. This article documents this data set and presents analyses of some of the data. The near infrared mapping spectrometer (NIMS) investigation obtained 17 separate mosaics of the Moon in 408 spectral channels between about 0.7 and 5.2 micrometers. The instrument was originally designed to operate in orbit about Jupiter and therefore saturates at many spectral channels for most measurement situations at 1 AU. However, sufficient measurements were made of the Moon to verify the proper operation of the instrument and to demonstrate its capabilities. Analysis of these data show that the NIMS worked as expected and produced measurements consistent with previous ground-based telescopic studies. These are the first imaging spectrometer measurements of this type from space for the Moon, and they illustrate several major points concerning this type of observation and about the NIMS capabilities specifically. Of major importance are the difference between framing and scanning instruments and the effects of the spacecraft and the scan platform on the performance of such and experiment. The science return of subsequent NIMS and other investigation measurements will be significantly enhanced by the experience and results gained.

  12. Properties of Jupiter's magnetospheric turbulence observed by the Galileo spacecraft

    Science.gov (United States)

    Tao, Chihiro; Sahraoui, Fouad; Fontaine, Dominique; Patoul, Judith; Chust, Thomas; Kasahara, Satoshi; Retinò, Alessandro

    2015-04-01

    In collisionless plasmas, turbulence is thought to play an important role in mass transport and energy dissipation. Magnetic fluctuations in the Jovian magnetosphere are essential in a turbulent state. Previous studies of that turbulence have focused on the large scales using low time resolution of magnetic field data. Here we extend those studies to cover a wider range of scales by combining both low and high-time-resolution data of Galileo magnetometer. We use particle data from the plasma instrument and include energetic particle contributions to estimate the local plasma parameters. We obtain 11 power spectra of magnetic field in the frequency range of 10-4-1 Hz, which covers both magnetohydrodynamics and ion kinetic scales. The frequencies of the evidenced spectral breaks are found to be relatively well correlated with the characteristic scales of heavy ion. The spectral indices below and above the spectral breaks are found to be broad and cover the ranges of 0.6-1.9 and 1.7-2.5, respectively. An analysis of higher-order statistics shows an intermittent feature of the turbulence, found to be more prominent in the plasma sheet than in the lobe. Furthermore, a statistical survey of the power of the fluctuations using low-time-resolution data suggests a radially varying dawn-dusk asymmetry: the total power is larger in the duskside (dawnside) at 80 RJ), which would reflect flow shear and global magnetospheric activity.

  13. Io Plasma Torus Ion Composition: Voyager, Galileo, Cassini

    Science.gov (United States)

    Bagenal, Fran; Nerney, Edward; Steffl, Andrew Joseph

    2016-10-01

    With JAXA's Hisaki spacecraft in orbit around Earth gathering information on the Io plasma torus and NASA's Juno mission measuring plasma conditions in the jovian magnetosphere, the time is ripe for a re-evaluation of earlier observations of the plasma torus to assess evidence for temporal variations. In particular, we are interested in exploring the ion composition of the torus and whether there is evidence of the ultimate source – the volcanic gases from Io – have deviated from SO2. We use the latest CHIANTI 8.0 atomic database to analyze UV spectra of the torus from Voyager, Galileo and Cassini as well as with the physical chemistry model of Delamere, Steffl and Bagenal (2005). We find that contrary to earlier analyses of Voyager data (e.g. Shemansky 1987; 1988) that produced a composition requiring a neutral source of O/S~4, we find an ion composition that is consistent with the Cassini UVIS data (Steffl et al. 2004) and a neutral O/S~2, consistent with SO2.

  14. Bipropellant rocket exhaust plume analysis on the Galileo spacecraft

    Science.gov (United States)

    Guernsey, C. S.; Mcgregor, R. D.

    1986-01-01

    This paper describes efforts to quantify the contaminant flow field produced by 10 N thrust bipropellant rocket engines used on the Galileo spacecraft. The prediction of the composition of the rocket exhaust by conventional techniques is found to be inadequate to explain experimental observations of contaminant deposition on moderately cold (200 K) surfaces. It is hypothesized that low volatility contaminants are formed by chemical reactions which occur on the surfaces. The flow field calculations performed using the direct simulation Monte Carlo method give the expected result that the use of line-of-sight plume shields may have very little effect on the flux of vapor phase contaminant species to a surface, especially if the plume shields are located so close to the engine that the interaction of the plume with the shield is in the transition flow regime. It is shown that significant variations in the exhaust plume composition caused by nonequilibrium effects in the flow field lead to very low concentrations of species which have high molecular weights in the more rarefied regions of the flow field. Recommendations for the design of spacecraft plume shields and further work are made.

  15. Short-term GNSS satellite clock stability

    Science.gov (United States)

    Griggs, E.; Kursinski, E. R.; Akos, D.

    2015-08-01

    Global Navigation Satellite System (GNSS) clock stability is characterized via the modified Allan deviation using active hydrogen masers as the receiver frequency reference. The high stability of the maser reference allows the GNSS clock contribution to the GNSS carrier phase variance to be determined quite accurately. Satellite clock stability for four different GNSS constellations are presented, highlighting the similarities and differences between the constellations as well as satellite blocks and clock types. Impact on high-rate applications, such as GNSS radio occultation (RO), is assessed through the calculation of the maximum carrier phase error due to clock instability. White phase noise appears to dominate at subsecond time scales. However, while we derived the theoretical contribution of white phase modulation to the modified Allan deviation, our analysis of the GNSS satellite clocks was limited to 1-200 s time scales because of inconsistencies between the subsecond results from the commercial and software-defined receivers. The rubidium frequency standards on board the Global Positioning System (GPS) Block IIF, BeiDou, and Galileo satellites show improved stability results in comparison to previous GPS blocks for time scales relevant to RO. The Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS) satellites are the least stable of the GNSS constellations in the short term and will need high-rate corrections to produce RO results comparable to those from the other GNSS constellations.

  16. Precision Measurement and Calibration. Volume 1. Statistical Concepts and Procedures

    Science.gov (United States)

    1969-02-01

    Sons, New York. N.Y.). Shewhart, Walter A. (19t39), Statistical Method frin the Galilei , Galileo (1638), Discorsi e Dirnostrazioni Matema- Viewpoint... Galilei . Galileo (1898). Discorsi e Dimostraziorii Matemnaticlie Shiewhart, Walter A. (1941), (Contribiution of statistics to Initorno a Dine Ninove Scienze...Le Opere i Galileo Galilei the science of engineering, University of Pennsylvania Bi- (Edizione Nazionale) Vill, pp 39-448, Firenze. centennial

  17. Information content in reflected global navigation satellite system signals

    DEFF Research Database (Denmark)

    Høeg, Per; Carlstrom, Anders

    2011-01-01

    The direct signals from satellites in global satellite navigation satellites systems (GNSS) as, GPS, GLONASS and GALILEO, constitute the primary source for positioning, navigation and timing from space. But also the reflected GNSS signals contain an important information content of signal travel...... times and the characteristics of the reflecting surfaces and structure. Ocean reflected signals from GNSS satellite systems reveal the mean height, the significant wave height and the roughness of the ocean. The estimated accuracy of the average surface height can be as low as 10 cm. For low elevations......, the signals reveal the incoherent scatter process at the reflection zone. By using open-loop high-precision GNSS receivers, it is possible to provide the in-phase and quadrature components of the signal at high sample rates, which enables investigation of the spectral signatures of the observations...

  18. GPS/Galileo组合定位和Galileo卫星钟评估%GPS/Galileo combined positioning and assessment of Galileo satellite clock

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    利用GPS/Galileo实测数据,采用GPS/Galileo组合定位模型,研究了目前Galileo在多系统组合定位中的作用.对GPS单系统、GPS/Galileo双系统在不同情况下的定位结果进行了比较分析.结果表明:在多遮挡环境下,GPS可视卫星数目较少时,加入Galileo卫星会明显改善PDOP值,且定位精度也显著提高.此外,对目前所观测到的Galileo在轨卫星钟性能进行了评估,评估结果表明Galileo的星钟频率稳定度(τ=300 s)在10-13量级.Galileo星钟评估将为下一步Galileo系统时间偏差监测提供依据.

  19. Satellite RNAs and Satellite Viruses.

    Science.gov (United States)

    Palukaitis, Peter

    2016-03-01

    Satellite RNAs and satellite viruses are extraviral components that can affect either the pathogenicity, the accumulation, or both of their associated viruses while themselves being dependent on the associated viruses as helper viruses for their infection. Most of these satellite RNAs are noncoding RNAs, and in many cases, have been shown to alter the interaction of their helper viruses with their hosts. In only a few cases have the functions of these satellite RNAs in such interactions been studied in detail. In particular, work on the satellite RNAs of Cucumber mosaic virus and Turnip crinkle virus have provided novel insights into RNAs functioning as noncoding RNAs. These effects are described and potential roles for satellite RNAs in the processes involved in symptom intensification or attenuation are discussed. In most cases, models describing these roles involve some aspect of RNA silencing or its suppression, either directly or indirectly involving the particular satellite RNA.

  20. Galileo and Descartes on Copernicanism and the cause of the tides.

    Science.gov (United States)

    Schmaltz, Tad M

    2015-06-01

    Galileo and Descartes were on the front lines of the defense of Copernicanism against theological objections that took on special importance during the seventeenth century. Galileo attempted to overcome opposition to Copernicanism within the Catholic Church by offering a demonstration of this theory that appeals to the fact that the double motion of the earth is necessary as a cause of the tides. It turns out, however, that the details of Galileo's tidal theory compromise his demonstration. Far from attempting to provide a demonstration of the earth's motion, Descartes ultimately argued that his system is compatible with the determination of the Church that the earth is at rest. Nonetheless, Descartes's account of the cause of the tides creates difficulty for this argument.

  1. Galileo, Keplero e la "nuova scienza" sul finire dellíumanesimo

    Science.gov (United States)

    Pani, Giancarlo

    At the end of the 16th century, Humanism seems to be an out of place working hypothesis. Nevertheless, it was a strong presence in philology and in rhetoric, but also in the new science, particularly in Galileo and in Kepler. Both of them were mathematicians, astronomers, and Copernicans, but they also were bound by delicate religious questions. Kepler, a Protestant, was excommunicated by the Lutheran Church because of his Calvinist ideas; Galileo, a Catholic, was excommunicated by the Holy Office, since he promoted heliocentrism. Their relationship was difficult, and marked by a reciprocal lack of understanding, the history of which is studied here. Still, Galileo and Kepler were highly creative scholars, founders of astronomy, and played a leading role in scientific progress.

  2. Re-evaluation of Galileo Energetic Particle Detector data - a correction model and comparison to semiconductor detector dead-layer sensitivity losses using SRIM

    Science.gov (United States)

    Lee-Payne, Zoe Hannah

    2016-10-01

    The Energetic Particle Detector launched in 1989 on the Galileo satellite took data on the Jovian Particle environment for 8 years before its demise. Over the course of the mission the detectors in the Composition Measurement System (CMS) have visibly decayed with higher mass particles, specifically oxygen and sulphur, reading far lower energies at later epochs. By considering the non-steady accumulation of damage in the detector, as well as the operation of the priority channel data recording system in place on the EPD, an evolving correction can be made. The recalibration significance can be validated using a model of dead layer build-up in semiconductor detectors, based on SRIM results. The final aim is to assign an estimation dead-layer depth during the mission data recordings.

  3. Transformational Leadership & Professional Development for Digitally Rich Learning Environments: A Case Study of the Galileo Educational Network.

    Science.gov (United States)

    Jacobsen, Michele; Clifford, Pat; Friesen, Sharon

    The Galileo Educational Network is an innovative educational reform initiative that brings learning to learners. Expert teachers work alongside teachers and students in schools to create new images of engaged learning, technology integration and professional development. This case study is based on the nine schools involved with Galileo in…

  4. Centriolar satellites

    DEFF Research Database (Denmark)

    Tollenaere, Maxim A X; Mailand, Niels; Bekker-Jensen, Simon

    2015-01-01

    Centriolar satellites are small, microscopically visible granules that cluster around centrosomes. These structures, which contain numerous proteins directly involved in centrosome maintenance, ciliogenesis, and neurogenesis, have traditionally been viewed as vehicles for protein trafficking...... highlight newly discovered regulatory mechanisms targeting centriolar satellites and their functional status, and we discuss how defects in centriolar satellite components are intimately linked to a wide spectrum of human diseases....

  5. Comparison of Galileo Probe and Earth-Based Translation Rates of Jupiter's Equatorial Clouds

    Science.gov (United States)

    Beebe; Simon; Huber

    1996-05-10

    The Doppler wind speeds derived from Galileo probe data are comparable with the maximum translation speeds observed in the equatorial zone by Voyager 1 and the Hubble Space Telescope. Slower published values of east-west winds are based on measurements of larger features and should be interpreted as translation rates of large weather systems interacting with the wind. The nature of the hot-spot region that the Galileo probe entered is compatible with a high-speed jet at 6 degrees north. The hot spot is associated with an equatorial weather system that spans 5 degrees of latitude and translates at 103 meters per second.

  6. Mission Jupiter. Die spektakuläre Reise der Raumsonde Galileo.

    Science.gov (United States)

    Fischer, D.

    Die Raumsonde Galileo ist 1989 gestartet und erforscht seit Dezember 1995 Jupiter und seine Monde. Erstmals ist eine Kapsel mit Meßinstrumenten in dem Gasriesen Jupiter versenkt worden. Die vier großen Jupitermonde wurden von Galileo umfassend erkundet. Seit Dezember 1997 ist die Primärmission abgeschlossen. Der Autor hat das Unternehmen mitverfolgt und schildert detailliert Planung und Ablauf der gesamten Mission. Sein Bericht wird ergänzt durch eine Auswahl der scönsten und wichtigsten Bilder.

  7. Between Copernicus and Galileo Christoph Clavius and the Collapse of Ptolemaic Cosmology

    CERN Document Server

    Lattis, James M

    1994-01-01

    Between Copernicus and Galileo is the story of Christoph Clavius, the Jesuit astronomer and teacher whose work helped set the standards by which Galileo's famous claims appeared so radical, and whose teachings guided the intellectual and scientific agenda of the Church in the central years of the Scientific Revolution. Though relatively unknown today, Clavius was enormously influential throughout Europe in the late sixteenth and early seventeenth centuries through his astronomy books—the standard texts used in many colleges and universities, and the tools with which Descartes, Gassendi, and Me

  8. Galileo's New Universe The Revolution in Our Understanding of the Cosmos

    CERN Document Server

    Maran, Stephen P

    2009-01-01

    The historical and social implications of the telescope and that instrument's modern-day significance are brought into startling focus in this fascinating account. When Galileo looked to the sky with his perspicillum, or spyglass, roughly 400 years ago, he could not have fathomed the amount of change his astonishing findings-a seemingly flat moon magically transformed into a dynamic, crater-filled orb and a large, black sky suddenly held millions of galaxies-would have on civilizations. Reflecting on how Galileo's world compares with contemporary society, this insightful analysis deftly moves

  9. Performance of the Fully Digital FPGA-based Front-End Electronics for the GALILEO Array

    CERN Document Server

    Barrientos, D; Bazzacco, D; Bortolato, D; Cocconi, P; Gadea, A; González, V; Gulmini, M; Isocrate, R; Mengoni, D; Pullia, A; Recchia, F; Rosso, D; Sanchis, E; Toniolo, N; Ur, C A; Valiente-Dobón, J J

    2014-01-01

    In this work we present the architecture and results of a fully digital Front End Electronics (FEE) read out system developed for the GALILEO array. The FEE system, developed in collaboration with the Advanced Gamma Tracking Array (AGATA) collaboration, is composed of three main blocks: preamplifiers, digitizers and preprocessing electronics. The slow control system contains a custom Linux driver, a dynamic library and a server implementing network services. The digital processing of the data from the GALILEO germanium detectors has demonstrated the capability to achieve an energy resolution of 1.53 per mil at an energy of 1.33 MeV.

  10. Satellite theory

    Science.gov (United States)

    Kozai, Y.

    1981-04-01

    The dynamical characteristics of the natural satellite of Mars, Jupiter, Saturn, Uranus and Neptune are analyzed on the basis of the solar tidal perturbation factor and the oblateness factor of the primary planet for each satellite. For the inner satellites, for which the value of the solar tidal factor is much smaller than the planetary oblateness factor, it is shown that the eccentricity and inclination of satellite orbits are generally very small and almost constant; several pairs of inner satellites are also found to exhibit commensurable mean motions, or secular accelerations in mean longitude. In the case of the outer satellites, for which solar perturbations are dominant, secular perturbations and long-period perturbations may be derived by the solution of equations of motion reduced to one degree of freedom. The existence of a few satellites, termed intermediary satellites, for which the solar tidal perturbation is on the order of the planetary oblateness factor, is also observed, and the pole of the orbital plane of the satellite is noted to execute a complex motion around the pole of the planet or the orbital plane of the planet.

  11. Mapping the Topography of Europa: The Galileo-Clipper Story

    Science.gov (United States)

    Schenk, Paul M.

    2014-11-01

    The renewed effort to return to Europa for global mapping and landing site selection raises the question: What do we know about Europa topography and how do we know it? The question relates to geologic questions of feature formation, to the issue of ice shell thickness, mechanical strength, and internal activity, and to landing hazards. Our topographic data base for Europa is sparse indeed (no global map is possible), but we are not without hope. Two prime methods have been employed in our mapping program are stereo image and shape-from-shading (PC) slope analyses. On Europa, we are fortunate that many PC-DEM areas are also controlled by stereo-DEMs, mitigating the long-wavelength uncertainties in the PC data. Due to the Galileo antenna malfunction, mapping is limited to no more than 20% of the surface, far less than for any of the inner planets. Thirty-seven individual mapping sites have been identified, scattered across the globe, and all have now been mapped. Excellent stereo mapping is possible at all Sun angles, if resolution is below ~350 m. PC mapping is possible at Sun angles greater than ~60 degrees, if emission angles are less than ~40 degrees. The only extended contiguous areas of topographic mapping larger than 150 km across are the two narrow REGMAP mapping mosaics extending pole-to-pole along longitudes 85 and 240 W. These are PC-only and subject to long-wavelength uncertainties and errors, especially in the north/south where oblique imaging produces layover. Key findings include the mean slopes of individual terrain types (Schenk, 2009), topography across chaos (Schenk and Pappalardo, 2004), topography of craters and inferences for ice shell thickness (Schenk, 2002; Schenk and Turtle, 2009), among others. A key discovery, despite the limited data, is that Europan terrains rarely have topographic amplitude greater than 250 meters, but that regionally Europa has imprinted on it topographic amplitudes of +/- 1 km, in the form of raised plateaus and

  12. Quantitative measurements of active Ionian volcanoes in Galileo NIMS data

    Science.gov (United States)

    Saballett, Sebastian; Rathbun, Julie A.; Lopes, Rosaly M. C.; Spencer, John R.

    2016-10-01

    Io is the most volcanically active body in our solar system. The spatial distribution of volcanoes a planetary body's surface gives clues into its basic inner workings (i.e., plate tectonics on earth). Tidal heating is the major contributor to active surface geology in the outer solar system, and yet its mechanism is not completely understood. Io's volcanoes are the clearest signature of tidal heating and measurements of the total heat output and how it varies in space and time are useful constraints on tidal heating. Hamilton et al. (2013) showed through a nearest neighbor analysis that Io's hotspots are globally random, but regionally uniform near the equator. Lopes-Gautier et al. (1999) compared the locations of hotspots detected by NIMS to the spatial variation of heat flow predicted by two end-member tidal heating models. They found that the distribution of hotspots is more consistent with tidal heating occurring in asthenosphere rather than the mantle. Hamilton et al. (2013) demonstrate that clustering of hotspots also supports a dominant role for asthenosphere heating. These studies were unable to account for the relative brightness of the hotspots. Furthermore, studies of the temporal variability of Ionian volcanoes have yielded substantial insight into their nature. The Galileo Near Infrared Mapping Spectrometer (NIMS) gave us a large dataset from which to observe active volcanic activity. NIMS made well over 100 observations of Io over an approximately 10-year time frame. With wavelengths spanning from 0.7 to 5.2 microns, it is ideally suited to measure blackbody radiation from surfaces with temperatures over 300 K. Here, we report on our effort to determine the activity level of each hotspot observed in the NIMS data. We decide to use 3.5 micron brightness as a proxy for activity level because it will be easy to compare to, and incorporate, ground-based observations. We fit a 1-temperature blackbody to spectra in each grating position and averaged the

  13. GALILEO/GPS中频接收的同步性能研究%Study on performance of IF GALILEO/GPS receivers synchronization

    Institute of Scientific and Technical Information of China (English)

    朱亚峰; 田增山; 周永胜

    2008-01-01

    本文针对GALILEO/GPS中频接收机同步跟踪性能问题进行研究.主要进行GPS扩频信号和GALILEO BOC(m,n)信号的自相关函数峰值的比较,GPS/GALILEO接收机码跟踪、载波跟踪的速率精度的比较,其中码跟踪采取了延迟锁相环(DLL),载波跟踪采用costas锁相环.从仿真的结果可以看出,扩频码自相关函数具有单峰值,而BOS(m,n)信号自相关函数具有多峰值的特点,GALILEO接收机具有锁相速度快、精度高的特点.

  14. GalileoMobile, sharing astronomy with students and teachers around the world

    Science.gov (United States)

    Benitez-Herrera, Sandra; Spinelli, Patricia F.

    2016-10-01

    GalileoMobile is a non-profit, itinerant, science outreach initiative that brings Astronomy closer to young people in areas with little or no access to outreach programs. We perform astronomy-related activities in schools and communities we visit and encourage follow-up activities through teacher training workshops and the donation of telescopes and other educational resources. GalileoMobile also extends its impact to a worldwide audience through deliverable products. Our work is shared worldwide through the production of documentaries, books and a wide range of Internet resources (OfficialWebsite - www.galileo-mobile.org - and Blog, Facebook page, Google+,Twitter, Youtube and Vimeo). GalileoMobile is an unprecedented initiative promoting science knowledge and the interaction beyond borders through Astronomy while raising awareness for the diversity of human cultures, conveying the message of ``unity under the same sky''. We take advantage of the local astronomical culture of the visited communities to establish a dialogue between different ways of understanding the world and to share different types of knowledge (historic, scientific, anthropological . . .), encouraging a process of mutual learning.

  15. Galileo (1564-1642) and Kepler (1571-1630): the modern scientist and the mystic

    CERN Document Server

    Todorov, Ivan

    2016-01-01

    The art of advertising one's scientific achievements, of which Galileo was an early master, is a trademark of successful modern science. Dedicated believers and mystics of science, such as Kepler, are less popular. Yet, an alleged rigorous rationalist like Wolfgang Pauli found in his later troubled life a kinship to Kepler's "archetypal ideas".

  16. Final safety analysis report for the Galileo Mission: Volume 1, Reference design document

    Energy Technology Data Exchange (ETDEWEB)

    1988-05-01

    The Galileo mission uses nuclear power sources called Radioisotope Thermoelectric Generators (RTGs) to provide the spacecraft's primary electrical power. Because these generators contain nuclear material, a Safety Analysis Report (SAR) is required. A preliminary SAR and an updated SAR were previously issued that provided an evolving status report on the safety analysis. As a result of the Challenger accident, the launch dates for both Galileo and Ulysses missions were later rescheduled for November 1989 and October 1990, respectively. The decision was made by agreement between the DOE and the NASA to have a revised safety evaluation and report (FSAR) prepared on the basis of these revised vehicle accidents and environments. The results of this latest revised safety evaluation are presented in this document (Galileo FSAR). Volume I, this document, provides the background design information required to understand the analyses presented in Volumes II and III. It contains descriptions of the RTGs, the Galileo spacecraft, the Space Shuttle, the Inertial Upper Stage (IUS), the trajectory and flight characteristics including flight contingency modes, and the launch site. There are two appendices in Volume I which provide detailed material properties for the RTG.

  17. Galileo SSI and Cassini ISS Observations of Io's Pele Hotspot: Temperatures, Areas, and Variation with Time

    Science.gov (United States)

    Radebaugh, J.; McEwen, A. S.; Milazzo, M.; Davies, A. G.; Keszthelyi, L. P.; Geissler, P.

    2002-01-01

    Temperatures of Io's Pele hotspot were found using dual-filter observations from Galileo and Cassini. Temperatures average 1375 K, but vary widely over tens of minutes. Dropoff in emission with rotation consistent with lava fountaining at a lava lake. Additional information is contained in the original extended abstract.

  18. Galileo SSI and Cassini ISS Observations of Io's Pele Hotspot: Temperatures, Areas, and Variation with Time

    Science.gov (United States)

    Radebaugh, J.; McEwen, A. S.; Milazzo, M.; Davies, A. G.; Keszthelyi, L. P.; Geissler, P.

    2002-01-01

    Temperatures of Io's Pele hotspot were found using dual-filter observations from Galileo and Cassini. Temperatures average 1375 K, but vary widely over tens of minutes. Dropoff in emission with rotation consistent with lava fountaining at a lava lake. Additional information is contained in the original extended abstract.

  19. Galileo's Last Fly-Bys of Io: NIMS Observations of Loki, Tupan, and Emakong Calderas

    Science.gov (United States)

    Lopes, Rosaly M. C.; Kamp, L. W.; Davies, A. G.; Smythe, W. D.; Carlson, R. W.; Doute, S.; McEwen, A.; Turtle, E. P.; Leader, F.; Mehlman, R.

    2002-01-01

    NIMS results from the 2001 Galileo fly-bys of Io will be presented, focusing on three calderas that may contain lava lakes. Preliminary results from the January 2002 Io fly-by will be presented. Additional information is contained in the original extended abstract.

  20. Galileo's 'Jumping-Hill' Experiment in the Classroom--A Constructivist's Analysis.

    Science.gov (United States)

    Kubli, Fritz

    2001-01-01

    Uses Galileo's 'jumping-hill' experiment as an historical element to improve science teaching in the classroom. Illustrates that the experiment can stimulate an animated discussion in the classroom, even if precise historic circumstances are not mentioned. The historical dimensions bring some color into the lesson, which increases attention. (SAH)

  1. William Whewell, Galileo, and reconceptualizing the history of science and religion.

    Science.gov (United States)

    Wilson, David B

    2011-12-20

    This paper advocates a reconceptualization of the history of science and religion. It is an approach to the subject that would aid research by historians of science as well as their message to others, both academic and non-academic. The approach is perfectly illustrated by the life and ideas of William Whewell and Galileo.

  2. Galileo CBOC信号跟踪的多径抑制方法及性能分析%Performance analysis on multipath mitigation techniques of Galileo CBOC signals' tracking

    Institute of Scientific and Technical Information of China (English)

    祝雪芬; 陈熙源

    2011-01-01

    Composite BOC (CBOC) modulation has been proposed for the future Galileo El OS. In order to mitigate the multipath's influence on Galileo CBOC tracking and improve the positioning precision, these two techniques, based on the description of the Galileo CBOC signals and the analysis of the narrow correlator and strobe correlator's discrimination function, are applied to mitigate the multipath's influence on CBOC signals. The Matlab simulation results indicate that both narrow correlator and strobe correlator can be applied to Galileo CBOC's multipath rejection. When the multipath delay is 200 ns, the performance of strobe correlator is 55.5% better than narrow correlator with the CBOC (6,1,1 /11) modulation.%针对未来Galileo E1频段拟采用的CBOC调制信号,研究如何消除多径对GalileoCBOC信号跟踪的影响,提高定位精度.在对Galileo CBOC调制技术进行描述,并对窄相关和Strobe相关的鉴别函数进行分析的基础上,将这两种多径抑制方法运用在Galileo CBOC信号跟踪的多径抑制方面.通过Matlab仿真实验得出,窄相关和Strobe相关均适用于Galileo CBOC调制信号,且CBOC(6,1,1/11)信号调制下,当取多径延迟为200ns时进行试验,Strobe相关较窄相关的多径抑制性能提高约55.5%.

  3. Sources of Error in Satellite Navigation Positioning

    Directory of Open Access Journals (Sweden)

    Jacek Januszewski

    2017-09-01

    Full Text Available An uninterrupted information about the user’s position can be obtained generally from satellite navigation system (SNS. At the time of this writing (January 2017 currently two global SNSs, GPS and GLONASS, are fully operational, two next, also global, Galileo and BeiDou are under construction. In each SNS the accuracy of the user’s position is affected by the three main factors: accuracy of each satellite position, accuracy of pseudorange measurement and satellite geometry. The user’s position error is a function of both the pseudorange error called UERE (User Equivalent Range Error and user/satellite geometry expressed by right Dilution Of Precision (DOP coefficient. This error is decomposed into two types of errors: the signal in space ranging error called URE (User Range Error and the user equipment error UEE. The detailed analyses of URE, UEE, UERE and DOP coefficients, and the changes of DOP coefficients in different days are presented in this paper.

  4. Identification of multiple binding sites for the THAP domain of the Galileo transposase in the long terminal inverted-repeats.

    Science.gov (United States)

    Marzo, Mar; Liu, Danxu; Ruiz, Alfredo; Chalmers, Ronald

    2013-08-01

    Galileo is a DNA transposon responsible for the generation of several chromosomal inversions in Drosophila. In contrast to other members of the P-element superfamily, it has unusually long terminal inverted-repeats (TIRs) that resemble those of Foldback elements. To investigate the function of the long TIRs we derived consensus and ancestral sequences for the Galileo transposase in three species of Drosophilids. Following gene synthesis, we expressed and purified their constituent THAP domains and tested their binding activity towards the respective Galileo TIRs. DNase I footprinting located the most proximal DNA binding site about 70 bp from the transposon end. Using this sequence we identified further binding sites in the tandem repeats that are found within the long TIRs. This suggests that the synaptic complex between Galileo ends may be a complicated structure containing higher-order multimers of the transposase. We also attempted to reconstitute Galileo transposition in Drosophila embryos but no events were detected. Thus, although the limited numbers of Galileo copies in each genome were sufficient to provide functional consensus sequences for the THAP domains, they do not specify a fully active transposase. Since the THAP recognition sequence is short, and will occur many times in a large genome, it seems likely that the multiple binding sites within the long, internally repetitive, TIRs of Galileo and other Foldback-like elements may provide the transposase with its binding specificity.

  5. The final Galileo SSI observations of Io: Orbits G28-I33

    Science.gov (United States)

    Turtle, E.P.; Keszthelyi, L.P.; McEwen, A.S.; Radebaugh, J.; Milazzo, M.; Simonelli, D.P.; Geissler, P.; Williams, D.A.; Perry, J.; Jaeger, W.L.; Klaasen, K.P.; Breneman, H.H.; Denk, T.; Phillips, C.B.

    2004-01-01

    We present the observations of Io acquired by the Solid State Imaging (SSI) experiment during the Galileo Millennium Mission (GMM) and the strategy we used to plan the exploration of Io. Despite Galileo's tight restrictions on data volume and downlink capability and several spacecraft and camera anomalies due to the intense radiation close to Jupiter, there were many successful SSI observations during GMM. Four giant, high-latitude plumes, including the largest plume ever observed on Io, were documented over a period of eight months; only faint evidence of such plumes had been seen since the Voyager 2 encounter, despite monitoring by Galileo during the previous five years. Moreover, the source of one of the plumes was Tvashtar Catena, demonstrating that a single site can exhibit remarkably diverse eruption styles - from a curtain of lava fountains, to extensive surface flows, and finally a ??? 400 km high plume - over a relatively short period of time (??? 13 months between orbits 125 and G29). Despite this substantial activity, no evidence of any truly new volcanic center was seen during the six years of Galileo observations. The recent observations also revealed details of mass wasting processes acting on Io. Slumping and landsliding dominate and occur in close proximity to each other, demonstrating spatial variation in material properties over distances of several kilometers. However, despite the ubiquitous evidence for mass wasting, the rate of volcanic resurfacing seems to dominate; the floors of paterae in proximity to mountains are generally free of debris. Finally, the highest resolution observations obtained during Galileo's final encounters with Io provided further evidence for a wide diversity of surface processes at work on Io. ?? 2003 Elsevier Inc. All rights reserved.

  6. Ion pick-up near the icy Galilean satellites

    Science.gov (United States)

    Volwerk, M.; Khurana, K. K.

    2010-12-01

    The ion pick-up near the icy Galilean satellites is studied using ion cyclotron waves. Using Galileo magnetometer data, we show evidence for the existence of ion cyclotron waves, which are generated by pick-up of freshly ionized particles. Near Europa, in the wake various kinds of ions are detected, which were already predicted to be present on the moon. Upstream of the moon there is evidence for water ion pick-up, which could facilitate the slow down of the plasma flow. Ganymede shows evidence for either water or oxygen pick up on the flanks of the magnetosphere. Callisto shows indication of hydrogen pick-up from its atmosphere.

  7. Analysis and Modeling of Jovian Radio Emissions Observed by Galileo

    Science.gov (United States)

    Menietti, J. D.

    2003-01-01

    Our studies of Jovian radio emission have resulted in the publication of five papers in refereed journals, with three additional papers in progress. The topics of these papers include the study of narrow-band kilometric radio emission; the apparent control of radio emission by Callisto; quasi-periodic radio emission; hectometric attenuation lanes and their relationship to Io volcanic activity; and modeling of HOM attenuation lanes using ray tracing. A further study of the control of radio emission by Jovian satellites is currently in progress. Abstracts of each of these papers are contained in the Appendix. A list of the publication titles are also included.

  8. Satellite Communications

    CERN Document Server

    Pelton, Joseph N

    2012-01-01

    The field of satellite communications represents the world's largest space industry. Those who are interested in space need to understand the fundamentals of satellite communications, its technology, operation, business, economic, and regulatory aspects. This book explains all this along with key insights into the field's future growth trends and current strategic challenges. Fundamentals of Satellite Communications is a concise book that gives all of the key facts and figures as well as a strategic view of where this dynamic industry is going. Author Joseph N. Pelton, PhD, former Dean of the International Space University and former Director of Strategic Policy at Intelstat, presents a r

  9. System design aspects and flight experience of the electrical interfaces across the Galileo spacecraft spin bearing assembly

    Science.gov (United States)

    Landano, Matthew R.

    1993-01-01

    The Galileo spacecraft design uses a dual-spin general configuration with spun and despun sections; the mechanical connection between the two sections is accomplished by means of a spin bearing assembly (SBA) whose electrical interfacing uses both slip rings/brushes and rotary transformers that are located within the SBA. Attention is presently given to the design features of the SBA, the electrical interface flight anomaly and investigation experience with Galileo to date, and the responses of the Galileo Flight Team to those anomalies.

  10. Satellite Geomagnetism

    DEFF Research Database (Denmark)

    Olsen, Nils; Stolle, Claudia

    2012-01-01

    Observations of Earth’s magnetic field from space began more than 50 years ago. A continuous monitoring of the field using low Earth orbit (LEO) satellites, however, started only in 1999, and three satellites have taken highprecision measurements of the geomagnetic field during the past decade...... ability to characterize and understand the many sources that contribute to Earth’s magnetic field. In this review, we summarize investigations of Earth’s interior and environment that have been possible through the analysis of high-precision magnetic field observations taken by LEO satellites........ The unprecedented time-space coverage of their data opened revolutionary new possibilities for monitoring, understanding, and exploring Earth’s magnetic field. In the near future, the three-satellite constellation Swarm will ensure continuity of such measurement and provide enhanced possibilities to improve our...

  11. Satellite (Natural)

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    In its most general sense, any celestial object in orbit around a similar larger object. Thus, for example, the Magellanic Clouds are satellite galaxies of our own Milky Way galaxy. Without qualification, the term is used to mean a body in orbit around a planet; an alternative term is moon. The term natural satellite distinguishes these bodies from artificial satellites—spacecraft placed in orbi...

  12. "Galileo's Machine": Late Notes on Free Fall, Projectile Motion, and the Force of Percussion (ca. 1638-1639)

    Science.gov (United States)

    Salvia, Stefano

    2014-12-01

    My paper focuses upon the problem of determining the nature, establishing the proportionality, and measuring the intensity of the force of percussion of a projected or falling body, as treated in the Sixth Day of Galileo's Discorsi e dimostrazioni matematiche intorno a due nuove scienze (1638). This fragment was written around 1638-1639 as part of two additional Days of the Discorsi, which Galileo never finished and remained unpublished until 1718. Galileo's last works on percussion show a significant step towards a generalization of his own views on uniform and accelerated motion that will later lead to the Newtonian principle of inertia. The experiment with two equal weights hanging on a pulley, performed in Arcetri during the same period, is compared with the Paduan 1604-1608 experience of the "water balance." Both account for more than three decades of inquiries into what Galileo called forza della percossa, which marked the transition from preclassical to classical mechanics.

  13. Využití platformy Intel Galileo v Internet of Things

    OpenAIRE

    Semančík, Matej

    2016-01-01

    Táto práca sa zaoberá využitím platformy Intel Galileo v IoT (Internet of Things) a jej porovnaním s ostatnými platformami, spôsobmi komunikácie v IoT, senzormi a senzorickými sieťami, spôsobmi implementácie tejto platformy, návrhom a realizáciou testovacej topológie. This thesis is about practical usage of Intel Galileo board in Internet of Things and it's comparison to other development platforms, communication types in IoT, sensors and sensor networks, implementation examples, proposal ...

  14. Comparison between Galileo CBOC Candidates and BOC(1,1 in Terms of Detection Performance

    Directory of Open Access Journals (Sweden)

    Fabio Dovis

    2008-01-01

    Full Text Available Many scientific activities within the navigation field have been focused on the analysis of innovative modulations for both GPS L1C and Galileo E1 OS, after the 2004 agreement between United States and European Commission on the development of GPS and Galileo. The joint effort by scientists of both parties has been focused on the multiplexed binary offset carrier (MBOC which is defined on the basis of its spectrum, and in this sense different time waveforms can be selected as possible modulation candidates. The goal of this paper is to present the detection performance of the composite BOC implementation of an MBOC signal in terms of detection and false alarm probabilities. A comparison among the CBOC and BOC(1,1 modulations is also presented to show how the CBOC solution, designed to have excellent tracking performance and multipath rejection capabilities, does not limit the acquisition process.

  15. In the sign of Galileo: pictorial representation in the 17th-century Copernican debate.

    Science.gov (United States)

    Remmert, Volker R

    2003-03-01

    After Galileo had discovered the four moons of Jupiter in 1609 he became increasingly convinced that the Copernican, heliocentric system of the world was correct. However, this ran against the opinions of the Church and a large number of contemporary astronomers and natural philosophers. The ensuing development culminated in the condemnation of the Copernican system by the Church in 1616 and of Galileo himself, who had propagated the Copernican system in his Dialogue Concerning the Two Chief World Systems (1632), in 1633. Nevertheless, there was a constant debate about the right world system during the whole 17th century. Pictorial representation played an important role in it and the illustrations used as book frontispieces were a significant medium for the dispute.

  16. Scientific Satellites

    Science.gov (United States)

    1967-01-01

    followed Hale’s into orbit. In 1879, Jules Verne wrote about launching small satellites with a gun possessing a muzzle velocity of 10 000 m/sec (ref. 3...was activated in 1950.11 It was located only a few tens of miles from the spot where Jules Verne had his Baltimore Gun Club fire a manned projectile to...principle, satellites can be launched by a single impulse applied at the Earth’s surface-say, with a large cannon, & la Jules Verne (sec. 8-3). In

  17. The Faces of Saturn: Images and Texts from Augustus through Dürer to Galileo

    Science.gov (United States)

    Shank, M. H.

    2013-04-01

    This paper follows the thread(s) of Saturn in astrology and art from the Babylonians to Galileo, paying special attention to the planet's political importance from Augustus to the Medici and to its medical/psychological significance from Ficino through Dürer. In passing, I extend David Pingree's astrological interpretation of Dürer's Melencholia I and propose a very personal rationale for the engraving, namely as a memorial to his mother.

  18. Computer predictions of ground storage effects on performance of Galileo and ISPM generators

    Science.gov (United States)

    Chmielewski, A.

    1983-01-01

    Radioisotope Thermoelectric Generators (RTG) that will supply electrical power to the Galileo and International Solar Polar Mission (ISPM) spacecraft are exposed to several degradation mechanisms during the prolonged ground storage before launch. To assess the effect of storage on the RTG flight performance, a computer code has been developed which simulates all known degradation mechanisms that occur in an RTG during storage and flight. The modeling of these mechanisms and their impact on the RTG performance are discussed.

  19. The transposon Galileo generates natural chromosomal inversions in Drosophila by ectopic recombination.

    Directory of Open Access Journals (Sweden)

    Alejandra Delprat

    Full Text Available BACKGROUND: Transposable elements (TEs are responsible for the generation of chromosomal inversions in several groups of organisms. However, in Drosophila and other Dipterans, where inversions are abundant both as intraspecific polymorphisms and interspecific fixed differences, the evidence for a role of TEs is scarce. Previous work revealed that the transposon Galileo was involved in the generation of two polymorphic inversions of Drosophila buzzatii. METHODOLOGY/PRINCIPAL FINDINGS: To assess the impact of TEs in Drosophila chromosomal evolution and shed light on the mechanism involved, we isolated and sequenced the two breakpoints of another widespread polymorphic inversion from D. buzzatii, 2z(3. In the non inverted chromosome, the 2z(3 distal breakpoint was located between genes CG2046 and CG10326 whereas the proximal breakpoint lies between two novel genes that we have named Dlh and Mdp. In the inverted chromosome, the analysis of the breakpoint sequences revealed relatively large insertions (2,870-bp and 4,786-bp long including two copies of the transposon Galileo (subfamily Newton, one at each breakpoint, plus several other TEs. The two Galileo copies: (i are inserted in opposite orientation; (ii present exchanged target site duplications; and (iii are both chimeric. CONCLUSIONS/SIGNIFICANCE: Our observations provide the best evidence gathered so far for the role of TEs in the generation of Drosophila inversions. In addition, they show unequivocally that ectopic recombination is the causative mechanism. The fact that the three polymorphic D. buzzatii inversions investigated so far were generated by the same transposon family is remarkable and is conceivably due to Galileo's unusual structure and current (or recent transpositional activity.

  20. Sensors for Location-Based Augmented Reality the Example of Galileo and Egnos

    Science.gov (United States)

    Pagani, Alain; Henriques, José; Stricker, Didier

    2016-06-01

    Augmented Reality has long been approached from the point of view of Computer Vision and Image Analysis only. However, much more sensors can be used, in particular for location-based Augmented Reality scenarios. This paper reviews the various sensors that can be used for location-based Augmented Reality. It then presents and discusses several examples of the usage of Galileo and EGNOS in conjonction with Augmented Reality.

  1. Timing Activities at INRIM in the Frame of the Galileo Project

    Science.gov (United States)

    2008-12-01

    RESEARCH On 1 January 2006, the Istituto Elettrotecnico Nazionale “Galileo Ferraris” (IEN) and the Istituto di Metrologia Gustavo Colonnetti...Hahn, 2008, “GNSS Interoperability: Offset between reference Time Scales and Timing Biases,” Metrologia , 45, 87-102. [13] R. Zanello, M...transfer to TAI using geodetic receivers,” Metrologia , 40, 184-188. 40th Annual Precise Time and Time Interval (PTTI) Meeting 656 [17] L. Galleani

  2. Galileo and the equivalence principle: a faulty argument with the correct conclusion

    Science.gov (United States)

    Hacyan, Shahen

    2015-11-01

    Galileo asserted that the fall of bodies is independent of their weight. Whether or not he relied on actual experiments, he explicitly argued in his writings that this fact could be proved by purely logical reasoning. However, there is an important flaw in the argument he provided. Clarification of this point may help one to grasp the full significance of the equivalence principle, which is usually overlooked in many physics courses.

  3. GalileoMobile, sharing astronomy with students and teachers around the world

    Science.gov (United States)

    Benitez-Herrera, S.; GalileoMobile Team

    2017-03-01

    GalileoMobile is a non-profit itinerant science outreach initiative that brings Astronomy closer to young people in areas with little or no access to outreach programs. We perform astronomy-related activities in schools and communities we visit and encourage follow-up activities through teacher training workshops and the donation of telescopes and other educational resources. GalileoMobile is an unprecedented initiative promoting science knowledge and the interaction beyond borders through Astronomy while raising awareness for the diversity of human cultures, conveying the message of unity under the same sky. We take advantage of the local astronomical culture of the visited communities to establish a dialogue between different ways of understanding the world and to share different types of knowledge (historic, scientific, anthropological...), encouraging a process of mutual learning. GalileoMobile is composed of 15 volunteer team members and more than 40 collaborators from different countries. Since its creation in 2008, we have organised expeditions in Chile, Bolivia and Peru (2009), Bolivia (2012), India (2012) and Uganda (2013), Brazil and Bolivia (2014), Colombia (2014) and extended actions in Portugal (2012, 2013), Nepal (2013), Guatemala (2013), Dominican Republic (2013), the United States (2013) and Haiti (2014). Our initiative for 2015, Constellation (www.constellationproject.org), aimed to establish a South American network of schools committed to the long-term organisation of astronomical outreach activities amongst their pupils and local communities. This project was supported by the Cosmic Light Project of the International Astronomical Union (IAU) and partially funded by the Office for Astronomy Development. In total, we have reached over 15,000 students; 1,400 teachers and 6,000 people in different communities over the past eight years. Our efforts and activities have been shared with the public in over 80 conferences and talks, including a TEDx talk

  4. Recent Korean R&D in Satellite Communications

    Science.gov (United States)

    Lee, Ho-Jin; Kim, Jae Moung; Lee, Byung-Seub; Lee, Han; Ryoo, Jang-Soo

    The R&D in satellite communications in Korea has been driven mainly by KCC (Korea Communications Commission) but in a small scale compared to Korea space development program organized by MEST (Ministry of Education, Science and Technology). Public and civilian satcom sector R&D has been led mainly by ETRI with small/medium companies contrary to rare investment in private sector while military sector R&D has been orchestrated by ADD with defense industry. By the COMS (Communication, Ocean and Meteorological Satellite) experimental Ka-band payload, Korea pursues a space qualification of own technology for national infrastructure evolution as well as industrialization of space R&D results. Once COMS launched and space qualified in 2009, subsequent application experiments and new technology R&D like UHDTV will entail service and industry promotion. The payload technology is expected for the next Korean commercial satellites or for new OBP satellites. The COMS ground control system and GNSS ground station technologies are under development for COMS operation and enhanced GNSS services along with advent of Galileo respectively. Satellite broadband mobile VSAT based on DVB-S2/RCS (+M) and low profile tracking antennas have been developed for trains, ships, and planes. While APSI is developing GMR-1 based Thuraya handset functions, ETRI is designing IMT-Advanced satellite radio interface for satellite and terrestrial dual-mode handheld communication system like Japanese STICS, with universities' satellite OFDM researches. A 21GHz Ka-band higher-availability scalable HD broadcasting technology and SkyLife's hybrid satellite IPTV technology are being developed. In near term Korea will extend R&D programs to upgrade the space communication infrastructure for universal access to digital opportunity and safer daily life from disaster, and to promote space green IT industrialization, national security, and space resources sovereign. Japanese stakeholders are invited to establish

  5. Characteristics and Soft-Demodulation of Galileo E1 Signal%Galileo E1信号特征及其软件解调

    Institute of Scientific and Technical Information of China (English)

    易翔

    2009-01-01

    Galileo E1民用信号采用新的BOC(1,1)扩频调制方式.针对E1信号进行信号建模,并对其信号特征进行了详细研究,最后设计了Galileo软件解调器中的信号处理模块.通过仿真验证表明,软件解调器成功实现了对Galileo E1信号的捕获、跟踪、解扩、解调全过程处理,克服了BOC解调的错锁问题.

  6. 伽利略与科学自由的边界探析--兼论科技干预的合理性问题%Galileo Galilei and Boundary of Science Freedom--On the Reasonability of Interference in Science and Technology

    Institute of Scientific and Technical Information of China (English)

    刘魁

    2004-01-01

    自伽利略受审等科学悲剧发生以后,科学自由就一直被视为科学家们的天赋权利,可是,社会发展的现实却告诉我们,科学自由不能够是无边界的、绝对的,而应该是有边界的、相对的.换句话说,社会应该在必要的条件下进行干预.为此,本文剖析了科学自由的内涵及其边界条件,探讨了科技干预的合理性问题.

  7. 基于DSP的Galileo/GPS联合导航定点算法研究%Research of Galileo/GPS Co-Navigation Fixed-point Positioning Algorithm Based on DSP

    Institute of Scientific and Technical Information of China (English)

    朱亮; 张钦宇; 罗嘉金; 初海彬

    2007-01-01

    文章对比了GPS、Galileo及Galileo/GPS 联合导航系统的性能,研究了基于最小二乘单点定位定点解算工程实现算法.仿真结果表明,Galileo/GPS联合导航较独立系统可见星数目、GDOP值及定位精度有明显的改善和提高.通过 TMS320C6416 DSP 硬件平台测试表明,研究的定点解算算法较浮点解算算法定位精度变化很小,具有较快的解算处理时间,为 Galileo/GPS 联合导航的实际应用打下了基础.

  8. Favelleran di te sempre le stelle Galileo, i primi Lincei e l'astronomia : Biblioteca dell'Accademia Nazionale dei Lincei e Corsiniana, Roma 6 aprile - 30 giugno 2009

    CERN Document Server

    Romanello, Alessandro; Trentini, Andrea

    2009-01-01

    Catalogo dell'esposizione del prezioso patrimonio custodito nella Biblioteca dell'Accademia dei Lincei, costituito da documenti manoscritti riguardanti gli esordi e da libri stampati di Galileo e su Galileo.

  9. Light Weight Radioisotope Heater Unit (LWRHU) production for the Galileo mission

    Science.gov (United States)

    Rinehart, Gary H.

    The Light Weight Radioisotope Heater Unit (LWRHU) is a (Pu-238)O2-fueled heat source designed to provide a thermal watt of power for space missions. The LWRHU will be used to maintain the temperature of various components on the spacecraft at the required level. The heat source consists of a (Pu-238)O2-fuel pellet, a Pt-30 pct Rh capsule, a pyrolytic graphite insulator, and a woven graphite aeroshell assembly. Los Alamos National Laboratory has fabricated 134 heater units which will be used on the Galileo mission.

  10. On the Impact of Channel Cross-Correlations in High-Sensitivity Receivers for Galileo E1 OS and GPS L1C Signals

    Directory of Open Access Journals (Sweden)

    Davide Margaria

    2012-01-01

    Full Text Available One of the most promising features of the modernized global navigation satellite systems signals is the presence of pilot channels that, being data-transition free, allow for increasing the coherent integration time of the receivers. Generally speaking, the increased integration time allows to better average the thermal noise component, thus improving the postcorrelation SNR of the receiver in the acquisition phase. On the other hand, for a standalone receiver which is not aided or assisted, the acquisition architecture requires that only the pilot channel is processed, at least during the first steps of the procedure. The aim of this paper is to present a detailed investigation on the impact of the code cross-correlation properties in the reception of Galileo E1 Open Service and GPS L1C civil signals. Analytical and simulation results demonstrate that the S-curve of the code synchronization loop can be affected by a bias around the lock point. This effect depends on the code cross-correlation properties and on the receiver setup. Furthermore, in these cases, the sensitivity of the receiver to other error sources might increase, and the paper shows how in presence of an interfering signal the pseudorange bias can be magnified and lead to relevant performance degradation.

  11. On the lost portrait of Galileo by the Tuscan painter Santi di Tito

    Science.gov (United States)

    Molaro, Paolo

    2016-12-01

    We study here the first established image of Galileo from the engraving made by Giuseppe Calendi at the end of the eighteenth century after a lost portrait of 1601 by Santi di Tito. We show that the engraving cannot be an exact copy, as it contains several inaccuracies which are unlikely to have been present in the original painting. A recent claim of the discovery of the painting by Santi di Tito is examined, and some reasons for suspecting it to be a forgery are outlined. As an alternative, we suggest a connection between the engraving and a portrait attributed to Tintoretto (which is currently in the collection of the Padua Civic Museum). The engraving and the Padua painting look quite different but can be traced to a common origin if we assume that Calendi added the half body, copied the painting onto copper plate directly, and adjusted the shading slightly. In this way, several features and details of the engraving find a plausible explanation. Finally, we note a remarkable similarity between the Padua portrait and a figure included in a Cologne painting by Rubens dating to about 1602-1604, which was suggested by Huemer to be Galileo.

  12. Analysis of Multispectral Galileo SSI Images of the Conamara Chaos Region, Europa

    Science.gov (United States)

    Spaun, N. A.; Phillips, C. B.

    2003-01-01

    Multispectral imaging of Europa s surface by Galileo s Solid State Imaging (SSI) camera has revealed two major surface color units, which appear as white and red-brown regions in enhanced color images of the surface (see figure). The Galileo Near- Infrared Mapping Spectrometer (NIMS) experiment suggests that the whitish material is icy, almost pure water ice, while the spectral signatures of the reddish regions are dominated by a non-ice material. Two endmember models have been proposed for the composition of the non-ice material: magnesium sulfate hydrates [1] and sulfuric acid and its byproducts [2]. There is also debate concerning whether the origin of this non-ice material is exogenic or endogenic [3].Goals: The key questions this work addresses are: 1) Is the non-ice material exogenic or endogenic in origin? 2) Once emplaced, is this non-ice material primarily modified by exogenic or endogenic processes? 3) Is the non-ice material within ridges, bands, chaos, and lenticulae the same non-ice material across all such geological features? 4) Does the distribution of the non-ice material provide any evidence for or against any of the various models for feature formation? 5) To what extent do the effects of scattered light in SSI images change the spectral signatures of geological features?

  13. Galileo multispectral imaging of the north polar and eastern limb regions of the moon

    Science.gov (United States)

    Belton, M.J.S.; Greeley, R.; Greenberg, R.; McEwen, A.; Klaasen, K.P.; Head, J. W.; Pieters, C.; Neukum, G.; Chapman, C.R.; Geissler, P.; Heffernan, C.; Breneman, H.; Anger, C.; Carr, M.H.; Davies, M.E.; Fanale, F.P.; Gierasch, P.J.; Ingersoll, A.P.; Johnson, T.V.; Pilcher, C.B.; Thompson, W.R.; Veverka, J.; Sagan, C.

    1994-01-01

    Multispectral images obtained during the Galileo probe's second encounter with the moon reveal the compositional nature of the north polar regions and the northeastern limb. Mare deposits in these regions are found to be primarily low to medium titanium lavas and, as on the western limb, show only slight spectral heterogeneity. The northern light plains are found to have the spectral characteristics of highlands materials, show little evidence for the presence of cryptomaria, and were most likely emplaced by impact processes regardless of their age.Multispectral images obtained during the Galileo probe's second encounter with the moon reveal the compositional nature of the north polar regions and the northeastern limb. Mare deposits in these regions are found to be primarily low to medium titanium lavas and, as on the western limb, show only slight spectral heterogeneity. The northern light plains are found to have the spectral characteristics of highlands materials, show little evidence for the presence of cryptomaria, and were most likely emplaced by impact processes regardless of their age.

  14. CONCEPTUAL PAPER : Utilization of GPS Satellites for Precise Irradiation Measurement and Monitoring

    Indian Academy of Sciences (India)

    S. Vijayan

    2008-03-01

    Precise measurement of irradiance over the earth under various circumstances like solar flares, coronal mass ejections, over an 11-year solar cycle, etc. leads to better understanding of Sun–earth relationship. To continuously monitor the irradiance over earth-space regions several satellites at several positions are required. For that continuous and multiple satellite monitoring we can use GPS (Global Positioning System) satellites (like GLONASS, GALILEO, future satellites) installed with irradiance measuring and monitoring instruments. GPS satellite system consists of 24 constellations of satellites. Therefore usage of all the satellites leads to 24 measurements of irradiance at the top of the atmosphere (or 12 measurements of those satellites which are pointing towards the Sun) at an instant. Therefore in one day, numerous irradiance observations can be obtained for the whole globe, which will be very helpful for several applications like Albedo calculation, Earth Radiation Budget calculation, monitoring of near earth-space atmosphere, etc. Moreover, measuring irradiance both in ground (using ground instruments) and in space at the same instant of time over a same place, leads to numerous advantages. That is, for a single position we obtain irradiance at the top of the atmosphere, irradiance at ground and the difference in irradiance from over top of the atmosphere to the ground. Measurement of irradiance over the atmosphere and in ground at a precise location gives more fine details about the solar irradiance influence over the earth, path loss and interaction of irradiance with the atmosphere.

  15. Geostationary Satellite (GOES) Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Visible and Infrared satellite imagery taken from radiometer instruments on SMS (ATS) and GOES satellites in geostationary orbit. These satellites produced...

  16. Studies of outer planet satellites, Mercury and Uranus

    Science.gov (United States)

    Mckinnon, William B.; Schenk, Paul M.

    1987-01-01

    Arguments were made, based on geometry, for both an impact and an internal origin for the ancient, partially preserved furrow system of Ganymede. It was concluded that furrows were not concentric, but could be impact related if multiringed structures on icy satellites are initially noncircular. The geometry of the Valhalla ring structure on Callisto was examined in order to assess the circularity of an unmodified ring system. The Ganymede furrow system was remapped to make use of improvements in coordinate control. The least-squares center of curvature for all furrows in the Marius and Galileao Regio is -20.7, and 179.2 degrees. Furrows in Marius and Galileo Regio are reasonably concentric, and are much more circular than previously estimated. The perceived present nonalignment of the assumed originally concentric furrows were used to argue for large-scale lateral motion of dark terrain blocks in Ganymede's crust, presumably in association with bright terrain formation., The overall alignment of furrows as well as the inherent scatter in centers of curvature from subregions of Galileo and Marius do not support this hypothesis.

  17. Neptune's small satellites

    Science.gov (United States)

    Thomas, P.

    1992-04-01

    The small satellites of Neptune and other planets discovered during the Voyager 2 mission are discussed in terms of their composition and relationship to the planetary systems. The satellite Proteus is described in terms of its orbit, five other satellites are described, and they are compared to ther small satellites and systems. Neptune's satellites are hypothesized to be related to the ring system, and the satellite Galatea is related to the confinement of the rings.

  18. Precise Orbit Determination of Earth's Satellites for Climate Change Investigation

    Science.gov (United States)

    Vespe, Francesco

    The tremendous improvement of the gravity field models which we are achieving with the last Earth's satellite missions like, CHAMP, GRACE and GOCE devoted to its recovery could make feasibile the use of precise orbit determination (POD) of Earth satellites as a tool for sensing global changes of some key atmosphere parameters like refractivity and extinction. Such improvements indeed, coupled with the huge number of running Earth's satellites and combinations of their orbital parameters (namely the nodes) in a gravity field free fashion (hereafter GFF) can magnify the solar radiation pressure acting on medium earth orbit satellites :GPS, Etalon and, in near real future GALILEO and its smooth modulation through the Earth's atmosphere (penumbra). We would remind that The GFF technique is able to cancel out with "n" satellite orbital parameters the first n-1 even zonal harmonics of the gravity field. Previously it was demonstrated that the signal we want to detect could in principle emerge from the noise threshold but, more refined models of the atmosphere would be needed to perform a more subtle analysis. So we will re-compute the signal features of penumbra by applying more refined atmospheric models. The analysis will be performed by including in GFF Earth's satellites equipped with DORIS systems (Jason, Spot 2-3-4-5, ENVISAT etc.) other than those ranged with SLR and GPS. The introduction of DORIS tracked satellites indeed will allow to cancel higher and higher order of even zonal harmonics and will make still more favourable the signal to noise budget. The analysis will be performed over a time span of at least few tens of years just to enhance probable climate signatures.

  19. The Gravity Fields of the Saturnian Satellites

    Science.gov (United States)

    Iess, L.

    2011-12-01

    In its tour of the Saturnian system, begun on July 1st, 2004, the Cassini spacecraft had many close flybys of Saturn's main satellites. However, due to impossibility to carry out simultaneously remote sensing observations and microwave tracking from ground, only a small fraction of those flybys could be exploited for gravity measurements. So far, the quadrupole field has been mapped only for Titan, Rhea and Enceladus, while for Hyperion and Iapetus the mass was the only accessible parameter. For Titan and Enceladus, the only satellites targeted more than once for gravity observations, also a rough geoid to degree and order 3 has been determined. Satellite gravity investigations rely upon accurate measurements of the spacecraft range rate, enabled by coherent, two-way radio links at X and Ka band (8.4 and 32.5 GHz). The use of hydrogen masers frequency standards at the ground station and the consid-erable suppression of plasma noise at X and Ka band frequen-cies provide range rate accuracies of 10-30 micron/s at integra-tion times of 60 s. Thanks to the higher frequency of the radio link, these measurement accuracies are in the average a factor of 10 better than those attained by Galileo in its tour of the Jovian system. However, in order to attain a reliable determination of the low degree field, good measurements must be combined with appropriate flyby geometries and adequate sampling, a condition that necessarily requires multiple flybys. We review the main results obtained so far by Cassini for Titan, Rhea and Enceladus, and discuss the methods of analysis used by the Radio Science Team.

  20. Simulation and Analysis of System Performance of GALILEO and Integrated GPS-GALILEO%基于GALILEO及GPS-GALILEO组合系统的仿真分析

    Institute of Scientific and Technical Information of China (English)

    赵春梅; 欧吉坤; 文援兰

    2005-01-01

    根据GALILEO卫星系统的设计参数,建立了卫星运动方程,编制了GALILEO系统的星座仿真软件;并结合GPS系统,以中国地壳运动观测网的25个基准站为地面观测站,对大陆范围内基于GPS、GALILEO以及GALILEO-GPS组合系统进行单点定位时的卫星可见性和给定精度下的定位可信度进行了系统的分析.仿真结果表明,在中国大陆范围内,GALILEO系统在时间域和空间域上的整体稳定性优于GPS系统.在一定的定位精度要求下,二者的平面定位可信度基本一致,GALILEO的高程定位可信度优于GPS系统;组合的GPS-GALILEO系统无论在卫星可见性方面,还是在定位可信度方面,均优于单一的定位系统.

  1. Fisica per poeti lo scienziato come uomo e artista : storia della fisica da Galileo ai giorni nostri

    CERN Document Server

    March, Robert H

    1994-01-01

    Un'intensa lezione di oggettività scientifica attraverso i secoli, alla ricerca delle verità ultime della natura. Da Galileo ad oggi, intuizioni, errori, grandi scoperte dei massimi protagonisti della fisica classica e moderna: la scienza vissuta come un'appassionante avventura.

  2. The Galileo Bias: A Naive Conceptual Belief That Influences People's Perceptions and Performance in a Ball-Dropping Task

    Science.gov (United States)

    Oberle, Crystal D.; McBeath, Michael K.; Madigan, Sean C.; Sugar, Thomas G.

    2005-01-01

    This research introduces a new naive physics belief, the Galileo bias, whereby people ignore air resistance and falsely believe that all objects fall at the same rate. Survey results revealed that this bias is held by many and is surprisingly strongest for those with formal physics instruction. In 2 experiments, 98 participants dropped ball pairs…

  3. Multivariate bootstrapped relative positioning of spacecraft using GPS L1/Galileo E1 signals

    Science.gov (United States)

    Buist, Peter J.; Teunissen, Peter J. G.; Giorgi, Gabriele; Verhagen, Sandra

    2011-03-01

    GNSS-based precise relative positioning between spacecraft normally requires dual frequency observations, whereas attitude determination of the spacecraft, mainly due to the stronger model given by the a priori knowledge of the length and geometry of the baselines, can be performed precisely using only single frequency observations. When the Galileo signals will come available, the number of observations at the L1 frequency will increase as we will have a GPS and Galileo multi-constellation. Moreover the L1 observations of the Galileo system and modernized GPS are more precise than legacy GPS and this, combined with the increased number of observations, will result in a stronger model for single frequency relative positioning. In this contribution we will develop an even stronger model by combining the attitude determination problem with relative positioning. The attitude determination problem will be solved by the recently developed Multivariate Constrained (MC-) LAMBDA method. We will do this for each spacecraft and use the outcome for an ambiguity constrained solution on the baseline between the spacecraft. In this way the solution for the unconstrained baseline is bootstrapped from the MC-LAMBDA solutions of each spacecraft in what is called: multivariate bootstrapped relative positioning. The developed approach will be compared in simulations with relative positioning using a single antenna at each spacecraft (standard LAMBDA) and a vectorial bootstrapping approach. In the simulations we will analyze single epoch, single frequency success rates as the most challenging application. The difference in performance for the approaches for single epoch solutions, is a good indication of the strength of the underlying models. As the multivariate bootstrapping approach has a stronger model by applying information on the geometry of the constrained baselines, for applications with large observation noise and limited number of observations this will result in a better

  4. The Foldback-like element Galileo belongs to the P superfamily of DNA transposons and is widespread within the Drosophila genus.

    Science.gov (United States)

    Marzo, Mar; Puig, Marta; Ruiz, Alfredo

    2008-02-26

    Galileo is the only transposable element (TE) known to have generated natural chromosomal inversions in the genus Drosophila. It was discovered in Drosophila buzzatii and classified as a Foldback-like element because of its long, internally repetitive, terminal inverted repeats (TIRs) and lack of coding capacity. Here, we characterized a seemingly complete copy of Galileo from the D. buzzatii genome. It is 5,406 bp long, possesses 1,229-bp TIRs, and encodes a 912-aa transposase similar to those of the Drosophila melanogaster 1360 (Hoppel) and P elements. We also searched the recently available genome sequences of 12 Drosophila species for elements similar to Dbuz\\Galileo by using bioinformatic tools. Galileo was found in six species (ananassae, willistoni, peudoobscura, persimilis, virilis, and mojavensis) from the two main lineages within the Drosophila genus. Our observations place Galileo within the P superfamily of cut-and-paste transposons and extend considerably its phylogenetic distribution. The interspecific distribution of Galileo indicates an ancient presence in the genus, but the phylogenetic tree built with the transposase amino acid sequences contrasts significantly with that of the species, indicating lineage sorting and/or horizontal transfer events. Our results also suggest that Foldback-like elements such as Galileo may evolve from DNA-based transposon ancestors by loss of the transposase gene and disproportionate elongation of TIRs.

  5. Cycle Slips Detection in Quad-Frequency Mode: Galileo's Contribution to an Efficient Approach under High Ionospheric Activity

    Science.gov (United States)

    Van de Vyvere, Laura; Warnant, René

    2016-04-01

    Cycle slips detection has always been a key issue in phase measurements accuracy, thus impacting positioning precision. Since Galileo is the first constellation to offer four carrier frequencies available in Open Service, we were able to develop an innovative detection algorithm, especially promising in harsh environment like high ionospheric activity. This improves previous dual and triple-frequency methods, whose efficiency was somehow limited in tricky situations, like ionospheric events or particular configurations. In our algorithm, two types of testing quantities were used: triple-frequency Simsky combination and dual-frequency Geometry-Free combination, each one being associated to a suitable detection algorithm. Simsky combination allows to detect almost every configuration, except for cycle slips of the same magnitude, appearing simultaneously on all carriers. Geometry-Free combination is only used to detect this particular case, since it suffers from quick variation of ionospheric delay. Together - through the choice of the most efficient combination alternatives - they enable the detection of any cycle slips configuration. This is now made possible thanks to the availability of data from Galileo's four carriers. The quad-frequency algorithm has been tested on Galileo observations from both GMSD (Japan) and NKLG (Gabon) stations. On the first ones, cycle slips were artificially inserted in order to simulate particular cases and test algorithm robustness. NKLG raw data were used to assess algorithm behaviour for cases met in the equatorial area. Enhanced with a suitable cycle slip correction method and a real-time feature, our algorithm could directly be integrated into the software receiver, enabling the supply of continuous and corrected data to the user. In conclusion, this first quad-frequency cycle slips detection algorithm is obviously a step forward and every Galileo user will indeed be able to benefit from a highly better-quality positioning. With

  6. The Sun: Our Nearest Star

    Science.gov (United States)

    Adams, M. L.; Six, N. Frank (Technical Monitor)

    2002-01-01

    We have in our celestial backyard, a prime example of a variable star. The Sun, long thought to be "perfect" and unvarying, began to reveal its cycles in the early 1600s as Galileo Galilei and Christoph Scheiner used a telescope to study sunspots. For the past four hundred years, scientists have accumulated data, showing a magnetic cycle that repeats, on average, every eleven (or twenty-two) years. In addition, modern satellites have shown that the energy output at radio and x-ray wavelengths also varies with this cycle. This talk will showcase the Sun as a star and discuss how solar studies may be used to understand other stars.

  7. The Tuscan Artist - Images of Galileo in Milton’s works

    Directory of Open Access Journals (Sweden)

    Toscano Fabio

    2004-09-01

    Full Text Available In The Areopagitica, his most important work of prose, John Milton mentions Galileo as the illustrious martyr who fought for the freedom of thought. The name of the great scientist is repeated several times in the English poet’s epic masterpiece: Paradise Lost. In three different passages of the poem, Milton in fact celebrates the “Tuscan Artist” and his crucial achievements in astronomy. Nevertheless, in a subsequent passage, the poet addresses the Copernican issue without openly defending the heliocentric theory confirmed by Galileo’s discoveries. In fact, he neither embraces the Copernican system nor the Ptolemaic one, but instead compares them, following a dialectic method where one cannot fail to notice an echo of Galileo’s Dialogue Concerning the two Chief World Systems. Milton’s literary work presents images of astronomy at that time, thus offering a valuable historical example of scientific communication through art.

  8. Final safety analysis report for the Galileo Mission: Volume 2, Book 2: Accident model document: Appendices

    Energy Technology Data Exchange (ETDEWEB)

    1988-12-15

    This section of the Accident Model Document (AMD) presents the appendices which describe the various analyses that have been conducted for use in the Galileo Final Safety Analysis Report II, Volume II. Included in these appendices are the approaches, techniques, conditions and assumptions used in the development of the analytical models plus the detailed results of the analyses. Also included in these appendices are summaries of the accidents and their associated probabilities and environment models taken from the Shuttle Data Book (NSTS-08116), plus summaries of the several segments of the recent GPHS safety test program. The information presented in these appendices is used in Section 3.0 of the AMD to develop the Failure/Abort Sequence Trees (FASTs) and to determine the fuel releases (source terms) resulting from the potential Space Shuttle/IUS accidents throughout the missions.

  9. Effusion Rate Variability at Zamama, Culann, Tupan Patera and Prometheus on Io during the Galileo Era

    Science.gov (United States)

    Davies, A. G.; Ennis, M. E.

    2011-10-01

    Zamama, Culann, and Tupan Patera are three large, persistent volcanic centers on the jovian moon Io. As part of an ongoing project to quantify contributions from individual volcanic centers to Io's thermal budget, we have quantified the radiant flux and effusion rates from all suitable observations made by the Galileo Near Infrared Mapping Spectrometer (NIMS) of these volcanoes [1], in some cases filling omissions in previous analyses. Eruption rates at these three volcanoes are on the order of 30 m3 s-1, consistent with a previous analysis of NIMS observations of Prometheus [2], and nearly an order of magnitude greater than Kilauea volcano, Hawai'i, Earth's most active volcano. We propose that future missions to the jovian system could better constrain activity at these volcanoes and others where similar styles of activity are taking place by obtaining data on a time scale of, ideally, at least one observation per day.

  10. Lunar impact basins and crustal heterogeneity - New western limb and far side data from Galileo

    Science.gov (United States)

    Belton, Michael J. S.; Head, James W., III; Pieters, Carle M.; Greeley, Ronald; Mcewen, Alfred S.; Neukum, Gerhard; Klaasen, Kenneth P.; Anger, Clifford D.; Carr, Michael H.; Chapman, Clark R.

    1992-01-01

    Multispectral images of the lunar western limb and far side obtained from Galileo reveal the compositional nature of several prominent lunar features and provide new information on lunar evolution. The data reveal that the ejecta from the Orientale impact basin (900 kilometers in diameter) lying outside the Cordillera Mountains was excavated from the crust, not the mantle, and covers pre-Orientale terrain that consisted of both highland materials and relatively large expanses of ancient mare basalts. The inside of the far side South Pole-Aitken basin (greater than 2000 kilometers in diameter) has low albedo, red color, and a relatively high abundance of iron- and magnesium-rich materials. These features suggest that the impact may have penetrated into the deep crust or lunar mantle or that the basin contains ancient mare basalts that were later covered by highlands ejecta.

  11. Further results from PIXE analysis of inks in Galileo's notes on motion

    Science.gov (United States)

    Del Carmine, P.; Giuntini, L.; Hooper, W.; Lucarelli, F.; Mandò, P. A.

    1996-06-01

    We have recently analysed the inks in some of the folios of Vol. 72 of Manoscritti galileiani, kept at the Biblioteca Nazionale Centrale di Firenze, which contains a collection of loose handwritten sheets containing undated notes, data from experiments and propositions on the problems of motion from different periods of Galileo's life. This paper reports specific results obtained from the analysis of some of these propositions, which allowed to make a contribution to their chronological attribution and therefore to the solution of some historical controversies. Even in the case where the "absolute" chronological attributions could not be made on the basis of comparison with dated documents, the PIXE results provided useful information to deny or confirm the hypothesis that different propositions were written in the same or in different periods.

  12. Galileo PPR at Io: High Resolution Scans Taken in Conjunction with SSA and NIMS Data

    Science.gov (United States)

    Rathbun, J. A.; Spencer, J. R.; Tamppari, L. K.; Martin, T. Z.; Barnard, L.; Travis, L. D.

    2003-01-01

    The Galileo Photopolarimeter-Radiometer (PPR), when used in the radiometry mode which is most often used at Io, is a long-wavelength infrared single-aperture photometer. It is sensitive to temperatures from about 60 to several hundred K, and is thus useful for studying the volcanoes and background temperatures on Io. PPR can take raster scan images when it is the primary instrument being used (these data were discussed last year, see Rathbun et al., 2002). It can also take data in ride-along mode in conjunction with another remote sensing instrument (either SSI or NIMS) producing one-dimensional temperature scans. The best data of this type were taken during the close approach flybys during orbits I24, I25, I27, I31, I32, and I33 and include measurements of the volcanoes Pele, Prometheus, Pillan, Zamama, Tvashtar, Daedalus, Amarani, Gish Bar, Isum, Emakong, Tupan, and Tohil.

  13. Safety analysis for the Galileo light-weight radioisotope heater unit

    Science.gov (United States)

    Johnson, Ernest W.

    The Light-Weight Radioisotope Heater Unit (LWRHU) will be used on the NASA Galileo Mission to provide thermal energy to the various systems on the orbiter and probe that are adversely affected by the low temperature a spacecraft encounters during a long interplanetary mission. Using these plutonia-fueled sources in 1-W increments permits employment of a single design and provides the spacecraft user the option of how many to use and where to position them to satisfy the proper thermal environment for components requiring such consideration. The use of the radioisotope Pu 238 in these devices necessitates the assessment of postulated radiological risks which might be experienced in case of accidents or malfunctions of the space shuttle or the spacecraft during phases of the mission in the vicinity of the earth. Included are data for the design, mission descriptions, postulated accidents with their consequences, test data, and the derived source terms and personnel exposures for the various events.

  14. Cassini RTG Acceptance Test Results and RTG Performance on Galileo and Ulysses

    Science.gov (United States)

    Kelly, C. E.; Klee, P. M.

    1997-06-01

    Flight acceptance testing has been completed for the RTGs to be used on the Cassini spacecraft which is scheduled for an October 6, 1997 launch to Saturn. The acceptance test program includes vibration tests, magnetic field measurements, properties (weight and c.g.) and thermal vacuum test. This paper presents The thermal vacuum test results. Three RTGs are to be used, F 2, F 6, and F 7. F 5 is tile back up RTG, as it was for the Galileo and Ulysses missions launched in 1989 and 1990, respectively. RTG performance measured during the thermal vacuum tests carried out at die Mound Laboratory facility met all specification requirements. Beginning of mission (BOM) and end of mission (EOM) power predictions have been made based on than tests results. BOM power is predicted to be 888 watts compared to the minimum requirement of 826 watts. Degradation models predict the EOM power after 16 years is to be 640 watts compared to a minimum requirement of 596 watts. Results of small scale module tests are also showing. The modules contain couples from the qualification and flight production runs. The tests have exceeded 28,000 hours (3.2 years) and are continuing to provide increased confidence in the predicted long term performance of the Cassini RTGs. All test results indicate that the power requirements of the Cassini spacecraft will be met. BOM and EOM power margins of over five percent are predicted. Power output from telemetry for the two Galileo RTGs are shown from the 1989 launch to the recent Jupiter encounter. Comparisons of predicted, measured and required performance are shown. Telemetry data are also shown for the RTG on the Ulysses spacecraft which completed its planned mission in 1995 and is now in the extended mission.

  15. BATMAN: a DMD-based multi-object spectrograph on Galileo telescope

    Science.gov (United States)

    Zamkotsian, Frederic; Spano, Paolo; Lanzoni, Patrick; Ramarijaona, Harald; Moschetti, Manuele; Riva, Marco; Bon, William; Nicastro, Luciano; Molinari, Emilio; Cosentino, Rosario; Ghedina, Adriano; Gonzalez, Manuel; Di Marcantonio, Paolo; Coretti, Igor; Cirami, Roberto; Zerbi, Filippo; Valenziano, Luca

    2014-07-01

    Next-generation infrared astronomical instrumentation for ground-based and space telescopes could be based on MOEMS programmable slit masks for multi-object spectroscopy (MOS). This astronomical technique is used extensively to investigate the formation and evolution of galaxies. We are developing a 2048x1080 Digital-Micromirror-Device-based (DMD) MOS instrument to be mounted on the Galileo telescope and called BATMAN. A two-arm instrument has been designed for providing in parallel imaging and spectroscopic capabilities. The field of view (FOV) is 6.8 arcmin x 3.6 arcmin with a plate scale of 0.2 arcsec per micromirror. The wavelength range is in the visible and the spectral resolution is R=560 for 1 arcsec object (typical slit size). The two arms will have 2k x 4k CCD detectors. ROBIN, a BATMAN demonstrator, has been designed, realized and integrated. It permits to determine the instrument integration procedure, including optics and mechanics integration, alignment procedure and optical quality. First images and spectra have been obtained and measured: typical spot diameters are within 1.5 detector pixels, and spectra generated by one micro-mirror slits are displayed with this optical quality over the whole visible wavelength range. Observation strategies are studied and demonstrated for the scientific optimization strategy over the whole FOV. BATMAN on the sky is of prime importance for characterizing the actual performance of this new family of MOS instruments, as well as investigating the operational procedures on astronomical objects. This instrument will be placed on the Telescopio Nazionale Galileo mid-2015.

  16. Cassini RTG acceptance test results and RTG performance on Galileo and Ulysses

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, C.E.; Klee, P.M. [Lockheed Martin Corp., Philadelphia, PA (United States)

    1997-12-31

    Flight acceptance testing has been completed for the RTGs to be used on the Cassini spacecraft which is scheduled for an October 6, 1997 launch to Saturn. The acceptance test program includes vibration tests, magnetic field measurements, mass properties (weight and c.g.) and thermal vacuum test. This paper presents the thermal vacuum test results. Three RTGs are to be used, F-2, F-6, and F-7. F-5 is the backup RTG, as it was for the Galileo and Ulysses missions launched in 1989 and 1990, respectively. RTG performance measured during the thermal vacuum tests carried out at the Mound Laboratory facility met all specification requirements. Beginning of mission (BOM) and end of mission (EOM) power predictions have been made based on these tests results. BOM power is predicted to be 888 watts compared to the minimum requirement of 826 watts. Degradation models predict the EOM power after 16 years is to be 640 watts compared to a minimum requirement of 596 watts. Results of small scale module tests are also shown. The modules contain couples from the qualification and flight production runs. The tests have exceeded 28,000 hours (3.2 years) and are continuing to provide increased confidence in the predicted long term performance of the Cassini RTGs. All test results indicate that the power requirements of the Cassini spacecraft will be met. BOM and EOM power margins of over 5% are predicted. Power output from telemetry for the two Galileo RTGs are shown from the 1989 launch to the recent Jupiter encounter. Comparisons of predicted, measured and required performance are shown. Telemetry data are also shown for the RTG on the Ulysses spacecraft which completed its planned mission in 1995 and is now in the extended mission.

  17. Disentangling plasma interaction and induction signatures at Callisto: The Galileo C10 flyby

    Science.gov (United States)

    Liuzzo, Lucas; Simon, Sven; Feyerabend, Moritz; Motschmann, Uwe

    2016-09-01

    We apply a combination of data analysis and hybrid modeling to study Callisto's interaction with Jupiter's magnetosphere during the Galileo C10 flyby on 17 September 1997. This encounter took place while Callisto was located near the center of Jupiter's current sheet. Therefore, induction in Callisto's subsurface ocean and magnetospheric field line draping around the moon's ionosphere both made nonnegligible contributions to the observed magnetic perturbations. The induction signal during C10 was obscured by plasma currents to a significant degree, in contrast to previously studied Callisto flybys. Our analysis reveals that at large distances to Callisto, its magnetic environment was dominated by field line draping, leading to the formation of Alfvén wings. Closer to the surface and in Callisto's wake, Galileo encountered a quasi-dipolar "core region" that was partially shielded from the plasma interaction and was dominated by the induced field. When exiting this core region, the spacecraft crossed a rotational discontinuity where the magnetic field vector rotated by approximately 50°. The hybrid model is able to quantitatively explain numerous key features of the observed magnetic signatures, especially the transitions between draping- and dipole-dominated regimes along the C10 trajectory. The model also reproduces the electron number density enhancement by 3-4 orders of magnitude detected in Callisto's wake, requiring a substantial ionosphere to surround the moon during C10. For flybys with nonnegligible plasma currents, comprehensive knowledge of the incident flow conditions and properties of Callisto's atmosphere is required to refine existing constraints on the subsurface ocean (conductivity, thickness, and depth) based on magnetic field data. These findings are highly relevant for the upcoming JUpiter ICy moon Explorer (JUICE) mission, which will include multiple Callisto flybys.

  18. Satellite data compression

    CERN Document Server

    Huang, Bormin

    2011-01-01

    Satellite Data Compression covers recent progress in compression techniques for multispectral, hyperspectral and ultra spectral data. A survey of recent advances in the fields of satellite communications, remote sensing and geographical information systems is included. Satellite Data Compression, contributed by leaders in this field, is the first book available on satellite data compression. It covers onboard compression methodology and hardware developments in several space agencies. Case studies are presented on recent advances in satellite data compression techniques via various prediction-

  19. Trends in communications satellites

    CERN Document Server

    Curtin, Denis J

    1979-01-01

    Trends in Communications Satellites offers a comprehensive look at trends and advances in satellite communications, including experimental ones such as NASA satellites and those jointly developed by France and Germany. The economic aspects of communications satellites are also examined. This book consists of 16 chapters and begins with a discussion on the fundamentals of electrical communications and their application to space communications, including spacecraft, earth stations, and orbit and wavelength utilization. The next section demonstrates how successful commercial satellite communicati

  20. The GalileoMobile starts its South American voyage - Astronomy education goes on tour through the Andes Mountains

    Science.gov (United States)

    2009-10-01

    Today marks the beginning of the GalileoMobile Project, a two-month expedition to bring the wonder and excitement of astronomy to young people in Chile, Bolivia and Peru. Supported by ESO and partners, a group of astronomers and educators will travel through a region of the Andes Mountains aboard the GalileoMobile, offering astronomical activities, such as workshops for students and star parties for the general public. Professional filmmakers on the trip will produce a multilingual documentary capturing the thrill of discovery through science, culture and travel. The GalileoMobile is a Special Project of the International Year of Astronomy 2009 (IYA2009), which is a global celebration commemorating the first use of a telescope to view the Universe by the Italian astronomer Galileo four hundred years ago. The project will promote basic science education through astronomy by visiting schools and communities that have limited access to outreach programmes. The GalileoMobile will provide these underserved groups with hands-on activities and educational material from international partners. The van is fully equipped to offer unique sky-observing opportunities for young students and other locals, with star parties at night and solar observations during the day. The team will use various tools including IYA2009's handy Galileoscopes, which will be donated to the schools after the visits. By stimulating curiosity, critical thinking and a sense of wonder and discovery for the Universe and our planet, the GalileoMobile Project aims to encourage interest in astronomy and science, and exchange culturally different visions of the cosmos. Spearheading the initiative is a group of enthusiastic Latin American and European PhD students from the European Southern Observatory, the Max Planck Society, the University Observatory Munich, and the Stockholm University Observatory. This itinerant educational programme is intended to reach about 20 000 people during eight weeks in October

  1. Design of Geodetic SVLBI Satellite Orbit and Its Tracking Network%SVLBI用于大地测量的卫星轨道及其跟踪网设计

    Institute of Scientific and Technical Information of China (English)

    魏二虎; 刘经南; KULKARNI M.N.; FREY Sándor

    2008-01-01

    SVLBI (space very long baseline interferometry) has some important potential applications in geodesy and geodynam- ics, for which one of the most difficult tasks is to precisely determine the orbit of an SVLBI satellite. This work studies several technologies that will possibly be able to determine the orbit of a space VLBI satellite. Then, according to the types and charac- teristics of the satellite and the requirements for geodetic study and the geometry of the GNSS (GPS, GALILEO) satellite to track the space VLBI satellite, the six Keplerian elements of the SVLBI satellite (TEST-SVLBI) are determined. A program is designed to analyze the coverage area of space of different altitudes by the stations of the network, with which the tracking network of TEST-SVLBI is designed. The efficiency of tracking TEST-SVLBI by the network is studied, and the results are presented.

  2. Xichang Satellite Launch Center

    Institute of Scientific and Technical Information of China (English)

    LiuJie

    2004-01-01

    Xichang Satellite Launch Center(XSLC) is mainly for geosynchronous orbit launches. The main purpose of XSLC is to launch spacecraft, such as broadcasting,communications and meteorological satellites, into geo-stationary orbit.Most of the commercial satellite launches of Long March vehicles have been from Xichang Satellite Launch Center. With 20 years' development,XSLC can launch 5 kinds of launch vehicles and send satellites into geostationary orbit and polar orbit. In the future, moon exploration satellites will also be launched from XSLC.

  3. Handbook of satellite applications

    CERN Document Server

    Madry, Scott; Camacho-Lara, Sergio

    2017-01-01

    The first edition of this ground breaking reference work was the most comprehensive reference source available about the key aspects of the satellite applications field. This updated second edition covers the technology, the markets, applications and regulations related to satellite telecommunications, broadcasting and networking—including civilian and military systems; precise satellite navigation and timing networks (i.e. GPS and others); remote sensing and meteorological satellite systems. Created under the auspices of the International Space University based in France, this brand new edition is now expanded to cover new innovative small satellite constellations, new commercial launching systems, innovation in military application satellites and their acquisition, updated appendices, a useful glossary and more.

  4. 爱克发推出Galileo Talant免冲洗电脑直接制版系统

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ 一、突破性的免冲洗、高印量烧蚀性热敏系统 爱克发突破性的Galileo Talant电脑直接制版系统为客户提供毋须冲洗的热敏制版操作.Galileo Talant兼备烧蚀性热敏的崭新技术与Galileo对开内鼓式的可靠设计,免除因冲洗处理而导致的高成本、延误、繁复工序以及成像问题,提高整个工作流程的效率.

  5. Novas espécies de Lamiinae (Cerambycidae neotropicais e transferência de Palpicrassus Galileo & Martins, 2007

    Directory of Open Access Journals (Sweden)

    Ubirajara R. Martins

    2010-01-01

    Full Text Available Novas espécies descritas do Brasil: Nesozineus amazonicus sp. nov. (Amazonas, Xenofrea diagonalis sp. nov. (Rondônia. Mauesia submetallica sp. nov. (Amazonas; da Bolívia: Psapharochrus nearnsi sp. nov. (Santa Cruz, Adetus basalis, sp. nov. (Santa Cruz, La Paz, Palpicrassus inexpectatus sp. nov. (Santa Cruz, Cyrtinus meridialis sp. nov. (Santa Cruz.. Do Panamá: Aerenea panamensis sp. nov. (Chiriqui. O gênero Palpicrassus Galileo & Martins, 2007, originalmente descrito em Pteropliini é transferido para Apomecynini.New species described from Brazil: Nesozineus amazonicus sp. nov. (Amazonas, Xenofrea diagonalis sp. nov. (Rondônia, Mauesia submetallica sp. nov. (Amazonas; from Bolivia: Psapharochrus nearnsi sp. nov. (Santa Cruz; Adetus basalis sp. nov. (Santa Cruz, La Paz, Palpicrassus inexpectatus sp. nov. (Santa Cruz, Cyrtinus meridialis sp. nov. (Santa Cruz., Aerenea panamensis sp. nov. from Panama (Chiriqui. The genus Palpicrassus Galileo & Martins, 2007, originally described in Pteropliini, is transferred to Apomecynini.

  6. La filosofía de Galileo y la conceptualización de la Causalidad Física

    OpenAIRE

    Martínez, Rafael

    1995-01-01

    Para Analizar La Relacion Existente Entre La Ciencia Y La Reflexion Filosofica,Resulta Necesario Examinar Los Conceptos Basicos Presupuestos Por Las Teoriascientificas, El Uso Que De Ellos Se Hace Y Su Evolucion. Este Analisis Puedefavorecer La Comprension Del Caracter Parcial Y Contextual, Pero Autentico, Dela Verdad Que La Ciencia Obtiene. Con Este Fin Se Examina El Concepto Decausalidad En Galileo, Mostrando Como Su Uso De Las Nociones Causales Manifiestauna Transformacion Mas Profunda De ...

  7. Satellite-Delivered Learning.

    Science.gov (United States)

    Arnall, Gail C.

    1987-01-01

    Discusses the application of satellite information delivery to training. Describes a new trend, horizontal programming. Also discusses vertical programming and in-house production of training materials. Lists vendors of satellite-based training. (CH)

  8. GPS Satellite Simulation Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The GPS satellite simulation facility consists of a GPS satellite simulator controlled by either a Silicon Graphics Origin 2000 or PC depending upon unit under test...

  9. China's Recoverable Satellites

    Institute of Scientific and Technical Information of China (English)

    Tang Boehang

    2008-01-01

    @@ By the end of 2006, China had launched 24 recoverable satellites (FSW) in total. Among them, 23 were launched successfully, of which all but one were successfully recovered. Recoverable satellites launched by China are listed in Table 1.

  10. Satellite Tags- Hawaii EEZ

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Satellite tagging was implemented in 2013. Satellite tagging is conducted using a Dan Inject air rifle and deployment arrows designed by Wildlife Computers. Two...

  11. Grooved Terrain on Ganymede: First Results from Galileo High-Resolution Imaging

    Science.gov (United States)

    Pappalardo, R.T.; Head, J.W.; Collins, G.C.; Kirk, R.L.; Neukum, G.; Oberst, J.; Giese, B.; Greeley, R.; Chapman, C.R.; Helfenstein, P.; Moore, Johnnie N.; McEwen, A.; Tufts, B.R.; Senske, D.A.; Herbert, Breneman H.; Klaasen, K.

    1998-01-01

    High-resolution Galileo imaging has provided important insight into the origin and evolution of grooved terrain on Ganymede. The Uruk Sulcus target site was the first imaged at high resolution, and considerations of resolution, viewing geometry, low image compression, and complementary stereo imaging make this region extremely informative. Contrast variations in these low-incidence angle images are extreme and give the visual impression of topographic shading. However, photometric analysis shows that the scene must owe its character to albedo variations. A close correlation of albedo variations to topography is demonstrated by limited stereo coverage, allowing extrapolation of the observed brightness and topographic relationships to the rest of the imaged area. Distinct geological units are apparent across the region, and ridges and grooves are ubiquitous within these units. The stratigraphically lowest and most heavily cratered units ("lineated grooved terrain") generally show morphologies indicative of horst-and-graben-style normal faulting. The stratigraphically highest groove lanes ("parallel ridged terrain") exhibit ridges of roughly triangular cross section, suggesting that tilt-block-style normal faulting has shaped them. These extensional-tectonic models are supported by crosscutting relationships at the margins of groove lanes. Thus, a change in tectonic style with time is suggested in the Uruk Sulcus region, varying from horst and graben faulting for the oldest grooved terrain units to tilt block normal faulting for the latest units. The morphologies and geometries of some stratigraphically high units indicate that a strike-slip component of deformation has played an important role in shaping this region of grooved terrain. The most recent tectonic episode is interpreted as right-lateral transtension, with its tectonic pattern of two contemporaneous structural orientations superimposed on older units of grooved terrain. There is little direct evidence for

  12. Satellite communication engineering

    CERN Document Server

    Kolawole, Michael Olorunfunmi

    2013-01-01

    An undeniably rich and thorough guide to satellite communication engineering, Satellite Communication Engineering, Second Edition presents the fundamentals of information communications systems in a simple and succinct way. This book considers both the engineering aspects of satellite systems as well as the practical issues in the broad field of information transmission. Implementing concepts developed on an intuitive, physical basis and utilizing a combination of applications and performance curves, this book starts off with a progressive foundation in satellite technology, and then moves on

  13. Taiyuan Satellite Launch Center

    Institute of Scientific and Technical Information of China (English)

    LiuJie

    2004-01-01

    There are three major space launch bases in China, the Jiuquan Satellite Launch Center,the Taiyuan Satellite Launch Center and the Xichang Satellite Launch Center. All the three launch centers are located in sparsely populated areas where the terrain is even and the field of vision is broad. Security, transport conditions and the influence of the axial rotation

  14. Geodetic Secor Satellite

    Science.gov (United States)

    1974-06-01

    simple, and had low-power lem. 17 14. Satellite Orientation . The satellite was designed to maintain a constant relationship between the antenna...the same satellite orientation . Further considerations were Th oscillations, however, when higher orbital ranges (500-2500 nautical miles) -, 3 a

  15. TC-2 Satellite Delivered

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    On April 18, 2005, TC-2, the second satellite of Double Star Program (DSP), which was jointly developed by CNSA and ESA, was approved to be delivered to the user after the on-board test and trial operation. The satellite is working well and the performance can meet the user's need. The satellite has collected large amount of valuable scientific data

  16. Lbs Augmented Reality Assistive System for Utilities Infrastructure Management Through Galileo and Egnos

    Science.gov (United States)

    Stylianidis, E.; Valaria, E.; Smagas, K.; Pagani, A.; Henriques, J.; Garca, A.; Jimeno, E.; Carrillo, I.; Patias, P.; Georgiadis, C.; Kounoudes, A.; Michail, K.

    2016-06-01

    There is a continuous and increasing demand for solutions, both software and hardware-based, that are able to productively handle underground utilities geospatial data. Innovative approaches that are based on the use of the European GNSS, Galileo and EGNOS, sensor technologies and LBS, are able to monitor, document and manage utility infrastructures' data with an intuitive 3D augmented visualisation and navigation/positioning technology. A software and hardware-based system called LARA, currently under develop- ment through a H2020 co-funded project, aims at meeting that demand. The concept of LARA is to integrate the different innovative components of existing technologies in order to design and develop an integrated navigation/positioning and information system which coordinates GNSS, AR, 3D GIS and geodatabases on a mobile platform for monitoring, documenting and managing utility infrastruc- tures on-site. The LARA system will guide utility field workers to locate the working area by helping them see beneath the ground, rendering the complexity of the 3D models of the underground grid such as water, gas and electricity. The capacity and benefits of LARA are scheduled to be tested in two case studies located in Greece and the United Kingdom with various underground utilities. The paper aspires to present the first results from this initiative. The project leading to this application has received funding from the European GNSS Agency under the European Union's Horizon 2020 research and innovation programme under grant agreement No 641460.

  17. From Comparison Between Scientists to Gaining Cultural Scientific Knowledge. Leonardo and Galileo

    Science.gov (United States)

    Galili, Igal

    2016-03-01

    Physics textbooks often present items of disciplinary knowledge in a sequential order of topics of the theory under instruction. Such presentation is usually univocal, that is, isolated from alternative claims and contributions regarding the subject matter in the pertinent scientific discourse. We argue that comparing and contrasting the contributions of scientists addressing similar or the same subject could not only enrich the picture of scientific enterprise, but also possess a special appealing power promoting genuine understanding of the concept considered. This approach draws on the historical tradition from Plutarch in distant past and Koyré in the recent history and philosophy of science. It gains a new support in the discipline-culture structuring of the physics curriculum, seeking cultural content knowledge (CCK) of the subject matter. Here, we address two prominent individuals of Italian Renaissance, Leonardo and Galileo, in their dealing with issues relevant for introductory science courses. Although both figures addressed similar subjects of scientific content, their products were essentially different. Considering this difference is educationally valuable, illustrating the meaning of what students presently learn in the content knowledge of mechanics, optics and astronomy, as well as the nature of science and scientific knowledge.

  18. Survey of the supporting research and technology for the thermal protection of the Galileo Probe

    Science.gov (United States)

    Howe, J. T.; Pitts, W. C.; Lundell, J. H.

    1981-01-01

    The Galileo Probe, which is scheduled to be launched in 1985 and to enter the hydrogen-helium atmosphere of Jupiter up to 1,475 days later, presents thermal protection problems that are far more difficult than those experienced in previous planetary entry missions. The high entry speed of the Probe will cause forebody heating rates orders of magnitude greater than those encountered in the Apollo and Pioneer Venus missions, severe afterbody heating from base-flow radiation, and thermochemical ablation rates for carbon phenolic that rival the free-stream mass flux. This paper presents a comprehensive survey of the experimental work and computational research that provide technological support for the Probe's heat-shield design effort. The survey includes atmospheric modeling; both approximate and first-principle computations of flow fields and heat-shield material response; base heating; turbulence modelling; new computational techniques; experimental heating and materials studies; code validation efforts; and a set of 'consensus' first-principle flow-field solutions through the entry maneuver, with predictions of the corresponding thermal protection requirements.

  19. Great Physicists - The Life and Times of Leading Physicists from Galileo to Hawking

    Science.gov (United States)

    Cropper, William H.

    2004-09-01

    Here is a lively history of modern physics, as seen through the lives of thirty men and women from the pantheon of physics. William H. Cropper vividly portrays the life and accomplishments of such giants as Galileo and Isaac Newton, Marie Curie and Ernest Rutherford, Albert Einstein and Niels Bohr, right up to contemporary figures such as Richard Feynman, Murray Gell-Mann, and Stephen Hawking. We meet scientists--all geniuses--who could be gregarious, aloof, unpretentious, friendly, dogged, imperious, generous to colleagues or contentious rivals. As Cropper captures their personalities, he also offers vivid portraits of their great moments of discovery, their bitter feuds, their relations with family and friends, their religious beliefs and education. In addition, Cropper has grouped these biographies by discipline--mechanics, thermodynamics, particle physics, and others--each section beginning with a historical overview. Thus in the section on quantum mechanics, readers can see how the work of Max Planck influenced Niels Bohr, and how Bohr in turn influenced Werner Heisenberg. Our understanding of the physical world has increased dramatically in the last four centuries. With Great Physicists , readers can retrace the footsteps of the men and women who led the way.

  20. Evaluation of Sulfur Flow Emplacement on Io from Galileo Data and Numerical Modeling

    Science.gov (United States)

    Williams, David A.; Greeley, Ronald; Lopes, Rosaly M. C.; Davies, Ashley G.

    2001-01-01

    Galileo images of bright lava flows surrounding Emakong Patera have bee0 analyzed and numerical modeling has been performed to assess whether these flows could have resulted from the emplacement of sulfur lavas on Io. Images from the solid-state imaging (SSI) camera show that these bright, white to yellow Emakong flows are up to 370 km long and contain dark, sinuous features that are interpreted to be lava conduits, -300-500 m wide and >lo0 km lorig. Neiu-Infrared Mapping S estimate of 344 K f 60 G131'C) within the Bmakong caldera. We suggest that these bright flows likely resulted from either sulfur lavas or silicate lavas that have undergone extensive cooling, pyroclastic mantling, and/or alteration with bright sulfurous materials. The Emakoag bright flows have estimated volume of -250-350 km', similar to some of the smaller Columbia River Basalt flows, If the Emakong flows did result from effusive sulfur eruptions, then they are orders of magnitude reater in volume than any terrestrial sulfur flows. Our numerical modeling capable of traveling tens to hundreds of kilometers, consistent with the predictions of Sagan. Our modeled flow distances are also consistent with the measured lengths of the Emakong channels and bright flows.

  1. Preliminary design of a NIR prime focus corrector for the Galileo Telescope

    CERN Document Server

    Pernechele, C; Conconi, P; Gardiol, D; Molinari, E; Zerbi, F M; Pernechele, Claudio; Bortoletto, Favio; Conconi, Paolo; Gardiol, Daniele; Molinari, Emilio; Zerbi, Filippo

    2000-01-01

    In this paper a preliminary design for a prime focus corrector to be mounted at the Telescopio Nazionale Galileo (TNG) is presented. The telescope is located on La Palma (Canary Islands) and has a primary mirror of 3.5 m with a hyperbolic sag. Two optical designs have been considered in order to exploit detectors with 1k x 1k and 2k x 2k pixels. Each design makes use of four lenses, two of which are aspherical. The first lens diameters are, respectively, of 140 mm and 320 mm for the two kind of detectors. For both designs the telescope pupil is deliberately not re-imaged, and therefore it will not be possible to insert a cold stop. For such a reason particular care has been dedicated to the telescope thermal background study, in order to optimise the baffling system. The optics is able to correct fields of 11' x 11' and of 60'x60', depending on the design. It should be considered that the particular geometry of the focal plane array mosaic does not permit a full exploitation of the entire field, being based o...

  2. Evolutionary Aspects for Technology Policy: the Case of Galileo Public-Private Partnership

    Science.gov (United States)

    Zervos, Vasilis

    2002-01-01

    This paper examines the impact of strategic interactions on Private-Public Partnerships (PPPs) in space. Though there is substantial business and economics literature on PPPs, it is traditionally focused on the relationships within the partnerships (low level) and the respective factors affecting its success. The contribution of this paper is that it examines the political economy of PPPs, analysing how `high-level' strategic interactions across public-private sectors in Europe and the US determine their behaviour and success. Within this context, the European case of Galileo and other national space projects, such as the US plans for a space-based anti- missile defence, are each based on different types of PPPs, confined within the geographical borders of the two areas. The security and commercial benefits of such programmes for the respective space industries and economies have a direct impact on the other area's industry and sense of security. The paper shows that trans- Atlantic cooperation at public policy level is essential to allow the respective industries to explore the benefits of cross-border strategic research partnerships (SRPs). This will reduce the costs of the respective programmes, addressing security concerns.

  3. Mountains on Io: High-resolution Galileo observations, initial interpretations, and formation models

    Science.gov (United States)

    Turtle, E.P.; Jaeger, W.L.; Keszthelyi, L.P.; McEwen, A.S.; Milazzo, M.; Moore, J.; Phillips, C.B.; Radebaugh, J.; Simonelli, D.; Chuang, F.; Schuster, P.; Alexander, D.D.A.; Capraro, K.; Chang, S.-H.; Chen, A.C.; Clark, J.; Conner, D.L.; Culver, A.; Handley, T.H.; Jensen, D.N.; Knight, D.D.; LaVoie, S.K.; McAuley, M.; Mego, V.; Montoya, O.; Mortensen, H.B.; Noland, S.J.; Patel, R.R.; Pauro, T.M.; Stanley, C.L.; Steinwand, D.J.; Thaller, T.F.; Woncik, P.J.; Yagi, G.M.; Yoshimizu, J.R.; Alvarez Del Castillo, E.M.; Beyer, R.; Branston, D.; Fishburn, M.B.; Muller, Birgit; Ragan, R.; Samarasinha, N.; Anger, C.D.; Cunningham, C.; Little, B.; Arriola, S.; Carr, M.H.; Asphaug, E.; Morrison, D.; Rages, K.; Banfield, D.; Bell, M.; Burns, J.A.; Carcich, B.; Clark, B.; Currier, N.; Dauber, I.; Gierasch, P.J.; Helfenstein, P.; Mann, M.; Othman, O.; Rossier, L.; Solomon, N.; Sullivan, R.; Thomas, P.C.; Veverka, J.; Becker, T.; Edwards, K.; Gaddis, L.; Kirk, R.; Lee, E.; Rosanova, T.; Sucharski, R.M.; Beebe, R.F.; Simon, A.; Belton, M.J.S.; Bender, K.; Fagents, S.; Figueredo, P.; Greeley, R.; Homan, K.; Kadel, S.; Kerr, J.; Klemaszewski, J.; Lo, E.; Schwarz, W.; Williams, D.; Williams, K.; Bierhaus, B.; Brooks, S.; Chapman, C.R.; Merline, B.; Keller, J.; Tamblyn, P.; Bouchez, A.; Dyundian, U.; Ingersoll, A.P.; Showman, A.; Spitale, J.; Stewart, S.; Vasavada, A.; Breneman, H.H.; Cunningham, W.F.; Johnson, T.V.; Jones, T.J.; Kaufman, J.M.; Klaasen, K.P.; Levanas, G.; Magee, K.P.; Meredith, M.K.; Orton, G.S.; Senske, D.A.; West, A.; Winther, D.; Collins, G.; Fripp, W.J.; Head, J. W.; Pappalardo, R.; Pratt, S.; Prockter, L.; Spaun, N.; Colvin, T.; Davies, M.; DeJong, E.M.; Hall, J.; Suzuki, S.; Gorjian, Z.; Denk, T.; Giese, B.; Koehler, U.; Neukum, G.; Oberst, J.; Roatsch, T.; Tost, W.; Wagner, R.; Dieter, N.; Durda, D.; Geissler, P.; Greenberg, R.J.; Hoppa, G.; Plassman, J.; Tufts, R.; Fanale, F.P.; Granahan, J.C.

    2001-01-01

    During three close flybys in late 1999 and early 2000 the Galileo spacecraft ac-quired new observations of the mountains that tower above Io's surface. These images have revealed surprising variety in the mountains' morphologies. They range from jagged peaks several kilometers high to lower, rounded structures. Some are very smooth, others are covered by numerous parallel ridges. Many mountains have margins that are collapsing outward in large landslides or series of slump blocks, but a few have steep, scalloped scarps. From these observations we can gain insight into the structure and material properties of Io's crust as well as into the erosional processes acting on Io. We have also investigated formation mechanisms proposed for these structures using finite-element analysis. Mountain formation might be initiated by global compression due to the high rate of global subsidence associated with Io's high resurfacing rate; however, our models demonstrate that this hypothesis lacks a mechanism for isolating the mountains. The large fraction (???40%) of mountains that are associated with paterae suggests that in some cases these features are tectonically related. Therefore we have also simulated the stresses induced in Io's crust by a combination of a thermal upwelling in the mantle with global lithospheric compression and have shown that this can focus compressional stresses. If this mechanism is responsible for some of Io's mountains, it could also explain the common association of mountains with paterae. Copyright 2001 by the American Geophysical Union.

  4. I grandi della fisica da Platone a Heisenberg

    CERN Document Server

    Von Weizsäcker, Carl Friedrich

    2002-01-01

    Parmenide ; Platone ; Aristotele ; Copernico, Keplero, Galilei ; Galileo Galilei ; Cartesio ; Gottfried Wilhelm Leibniz ; Cartesio, Newton, Leibniz, Kant ; Immanuel Kant ; Johann Wolfgang Goethe ; Robert Meyer ; Albert Einstein ; Niels Bohr ; Paul Adrien Maurice Dirac ; Niels Bohr e Werner Heisenberg, un ricordo del 1932 ; Werner Heisenberg ; Heisenberg, fisico e filosofo ; l'interpretazione filosofica della fisica moderna.

  5. Meteorological satellite systems

    CERN Document Server

    Tan, Su-Yin

    2014-01-01

    “Meteorological Satellite Systems” is a primer on weather satellites and their Earth applications. This book reviews historic developments and recent technological advancements in GEO and polar orbiting meteorological satellites. It explores the evolution of these remote sensing technologies and their capabilities to monitor short- and long-term changes in weather patterns in response to climate change. Satellites developed by various countries, such as U.S. meteorological satellites, EUMETSAT, and Russian, Chinese, Japanese and Indian satellite platforms are reviewed. This book also discusses international efforts to coordinate meteorological remote sensing data collection and sharing. This title provides a ready and quick reference for information about meteorological satellites. It serves as a useful tool for a broad audience that includes students, academics, private consultants, engineers, scientists, and teachers.

  6. Theory of geostationary satellites

    CERN Document Server

    Zee, Chong-Hung

    1989-01-01

    Geostationary or equatorial synchronous satellites are a daily reminder of our space efforts during the past two decades. The nightly television satellite weather picture, the intercontinental telecommunications of television transmissions and telephone conversations, and the establishrnent of educational programs in remote regions on Earth are constant reminders of the presence of these satellites. As used here, the term 'geo­ stationary' must be taken loosely because, in the long run, the satellites will not remain 'stationary' with respect to an Earth-fixed reference frame. This results from the fact that these satellites, as is true for all satellites, are incessantly subject to perturbations other than the central-body attraction of the Earth. Among the more predominant pertur­ bations are: the ellipticity of the Earth's equator, the Sun and Moon, and solar radiation pressure. Higher harmonics of the Earth's potential and tidal effects also influence satellite motion, but they are of second­ order whe...

  7. Precise orbit determination for quad-constellation satellites at Wuhan University: strategy, result validation, and comparison

    Science.gov (United States)

    Guo, Jing; Xu, Xiaolong; Zhao, Qile; Liu, Jingnan

    2016-02-01

    This contribution summarizes the strategy used by Wuhan University (WHU) to determine precise orbit and clock products for Multi-GNSS Experiment (MGEX) of the International GNSS Service (IGS). In particular, the satellite attitude, phase center corrections, solar radiation pressure model developed and used for BDS satellites are addressed. In addition, this contribution analyzes the orbit and clock quality of the quad-constellation products from MGEX Analysis Centers (ACs) for a common time period of 1 year (2014). With IGS final GPS and GLONASS products as the reference, Multi-GNSS products of WHU (indicated by WUM) show the best agreement among these products from all MGEX ACs in both accuracy and stability. 3D Day Boundary Discontinuities (DBDs) range from 8 to 27 cm for Galileo-IOV satellites among all ACs' products, whereas WUM ones are the largest (about 26.2 cm). Among three types of BDS satellites, MEOs show the smallest DBDs from 10 to 27 cm, whereas the DBDs for all ACs products are at decimeter to meter level for GEOs and one to three decimeter for IGSOs, respectively. As to the satellite laser ranging (SLR) validation for Galileo-IOV satellites, the accuracy evaluated by SLR residuals is at the one decimeter level with the well-known systematic bias of about -5 cm for all ACs. For BDS satellites, the accuracy could reach decimeter level, one decimeter level, and centimeter level for GEOs, IGSOs, and MEOs, respectively. However, there is a noticeable bias in GEO SLR residuals. In addition, systematic errors dependent on orbit angle related to mismodeled solar radiation pressure (SRP) are present for BDS GEOs and IGSOs. The results of Multi-GNSS combined kinematic PPP demonstrate that the best accuracy of position and fastest convergence speed have been achieved using WUM products, particularly in the Up direction. Furthermore, the accuracy of static BDS only PPP degrades when the BDS IGSO and MEO satellites switches to orbit-normal orientation

  8. Assessment of the Contribution of BeiDou GEO, IGSO, and MEO Satellites to PPP in Asia—Pacific Region

    Directory of Open Access Journals (Sweden)

    Qile Zhao

    2015-12-01

    Full Text Available In contrast to the US Global Positioning System (GPS, the Russian Global Navigation Satellite System (GLONASS and the European Galileo, the developing Chinese BeiDou satellite navigation system (BDS consists of not only Medium Earth Orbit (MEO, but also Geostationary Orbit (GEO as well as Inclined Geosynchronous Orbit (IGSO satellites. In this study, the Precise Point Positioning (PPP and PPP with Integer Ambiguity Resolution (IAR are obtained. The contributions of these three different types of BDS satellites to PPP in Asia-Pacific region are assessed using data from selected 20 sites over more than four weeks. By using various PPP cases with different satellite combinations, in general, the largest contribution of BDS IGSO among the three kinds of BDS satellites to the reduction of convergence time and the improvement of positioning accuracy, particularly in the east direction, is identified. These PPP cases include static BDS only solutions and static/kinematic ambiguity-float and -fixed PPP with the combination of GPS and BDS. The statistical results demonstrate that the inclusion of BDS GEO and MEO satellites can improve the observation condition and result in better PPP performance as well. When combined with GPS, the contribution of BDS to the reduction of convergence time is, however, not as significant as that of GLONASS. As far as the positioning accuracy is concerned, GLONASS improves the accuracy in vertical component more than BDS does, whereas similar improvement in horizontal component can be achieved by inclusion of BDS IGSO and MEO as GLONASS.

  9. Analysis of BeiDou Satellite Measurements with Code Multipath and Geometry-Free Ionosphere-Free Combinations.

    Science.gov (United States)

    Zhao, Qile; Wang, Guangxing; Liu, Zhizhao; Hu, Zhigang; Dai, Zhiqiang; Liu, Jingnan

    2016-01-20

    Using GNSS observable from some stations in the Asia-Pacific area, the carrier-to-noise ratio (CNR) and multipath combinations of BeiDou Navigation Satellite System (BDS), as well as their variations with time and/or elevation were investigated and compared with those of GPS and Galileo. Provided the same elevation, the CNR of B1 observables is the lowest among the three BDS frequencies, while B3 is the highest. The code multipath combinations of BDS inclined geosynchronous orbit (IGSO) and medium Earth orbit (MEO) satellites are remarkably correlated with elevation, and the systematic "V" shape trends could be eliminated through between-station-differencing or modeling correction. Daily periodicity was found in the geometry-free ionosphere-free (GFIF) combinations of both BDS geostationary Earth orbit (GEO) and IGSO satellites. The variation range of carrier phase GFIF combinations of GEO satellites is -2.0 to 2.0 cm. The periodicity of carrier phase GFIF combination could be significantly mitigated through between-station differencing. Carrier phase GFIF combinations of BDS GEO and IGSO satellites might also contain delays related to satellites. Cross-correlation suggests that the GFIF combinations' time series of some GEO satellites might vary according to their relative geometries with the sun.

  10. Analysis of BeiDou Satellite Measurements with Code Multipath and Geometry-Free Ionosphere-Free Combinations

    Directory of Open Access Journals (Sweden)

    Qile Zhao

    2016-01-01

    Full Text Available Using GNSS observable from some stations in the Asia-Pacific area, the carrier-to-noise ratio (CNR and multipath combinations of BeiDou Navigation Satellite System (BDS, as well as their variations with time and/or elevation were investigated and compared with those of GPS and Galileo. Provided the same elevation, the CNR of B1 observables is the lowest among the three BDS frequencies, while B3 is the highest. The code multipath combinations of BDS inclined geosynchronous orbit (IGSO and medium Earth orbit (MEO satellites are remarkably correlated with elevation, and the systematic “V” shape trends could be eliminated through between-station-differencing or modeling correction. Daily periodicity was found in the geometry-free ionosphere-free (GFIF combinations of both BDS geostationary Earth orbit (GEO and IGSO satellites. The variation range of carrier phase GFIF combinations of GEO satellites is −2.0 to 2.0 cm. The periodicity of carrier phase GFIF combination could be significantly mitigated through between-station differencing. Carrier phase GFIF combinations of BDS GEO and IGSO satellites might also contain delays related to satellites. Cross-correlation suggests that the GFIF combinations’ time series of some GEO satellites might vary according to their relative geometries with the sun.

  11. Relativistic positioning: errors due to uncertainties in the satellite world lines

    CERN Document Server

    Puchades, Neus

    2014-01-01

    Global navigation satellite systems use appropriate satellite constellations to get the coordinates of an user -close to Earth- in an almost inertial reference system. We have simulated both GPS and GALILEO constellations. Uncertainties in the satellite world lines lead to dominant positioning errors. In this paper, a detailed analysis of these errors is developed inside a great region surrounding Earth. This analysis is performed in the framework of the so-called relativistic positioning systems. Our study is based on the Jacobian, J, of the transformation giving the emission coordinates in terms of the inertial ones. Around points of vanishing J, positioning errors are too large. We show that, for any 4-tuple of satellites, the points with J=0 are located at distances, D, from the Earth centre greater than about 2R/3, where R is the radius of the satellite orbits which are assumed to be circumferences. Our results strongly suggest that, for D-distances greater than 2R/3 and smaller than 100000 km, a rather ...

  12. Advanced Multipath Mitigation Techniques for Satellite-Based Positioning Applications

    Directory of Open Access Journals (Sweden)

    Mohammad Zahidul H. Bhuiyan

    2010-01-01

    Full Text Available Multipath remains a dominant source of ranging errors in Global Navigation Satellite Systems (GNSS, such as the Global Positioning System (GPS or the future European satellite navigation system Galileo. Multipath is generally considered undesirable in the context of GNSS, since the reception of multipath can make significant distortion to the shape of the correlation function used for time delay estimation. However, some wireless communications techniques exploit multipath in order to provide signal diversity though in GNSS, the major challenge is to effectively mitigate the multipath, since we are interested only in the satellite-receiver transit time offset of the Line-Of-Sight (LOS signal for the receiver's position estimate. Therefore, the multipath problem has been approached from several directions in order to mitigate the impact of multipath on navigation receivers, including the development of novel signal processing techniques. In this paper, we propose a maximum likelihood-based technique, namely, the Reduced Search Space Maximum Likelihood (RSSML delay estimator, which is capable of mitigating the multipath effects reasonably well at the expense of increased complexity. The proposed RSSML attempts to compensate the multipath error contribution by performing a nonlinear curve fit on the input correlation function, which finds a perfect match from a set of ideal reference correlation functions with certain amplitude(s, phase(s, and delay(s of the multipath signal. It also incorporates a threshold-based peak detection method, which eventually reduces the code-delay search space significantly. However, the downfall of RSSML is the memory requirement which it uses to store the reference correlation functions. The multipath performance of other delay-tracking methods previously studied for Binary Phase Shift Keying-(BPSK- and Sine Binary Offset Carrier- (SinBOC- modulated signals is also analyzed in closed loop model with the new Composite

  13. Men of physics

    CERN Document Server

    Seeger, Raymond J

    2013-01-01

    Men of Physics: Galileo Galilei, His Life and His Works deals with Galileo Galilei's radical discoveries and trail during the Inquisition. The book describes the life of Galileo and his many interests in art and music, in addition to science. Galileo is born in Pisa in 1564, and at age 25, he is appointed to the Chair of Mathematics at the University of Pisa. He writes several papers, for example, mathematical continuum as contrasted with physical atomism, and investigates the behavior of magnetic poles. He believes in William Gilbert's experiment that the earth itself is a large magnet. He c

  14. «Una reflexión serena y objetiva». Galileo y el intento de autorrehabilitación de la Iglesia Católica

    Directory of Open Access Journals (Sweden)

    Beltrán, Antonio

    1998-05-01

    Full Text Available Not available.En 1979, el papa Juan Pablo II ordenaba una «reflexión serena y objetiva» sobre el caso Galileo. Posteriormente el pontífice ha reiterado el impulso y el respeto de la Iglesia a la libertad de la investigación y a la legítima autonomía de la ciencia. Aquí se examinan dos ejemplos de estas directrices y actitudes de la Iglesia. El primero es la interpretación de las condenas de Copérnico y Galileo que empezó a gestarse, tras la muerte de este último, en el seno de la Iglesia católica, y que hoy tiene su última versión en W. Brandmüller, uno de los miembros de la comisión papal para el estudio del caso Galileo, interpretación que diluye la gravedad de las condenas de 1616 y 1633 y atribuye a la Iglesia un escrúpulo científico que Galileo no habría tenido. El segundo ejemplo examinado es el «caso Paschini»: la censura y manipulación de su texto sobre Galileo por parte de las autoridades del Vaticano que se lo habían encargado.

  15. The GalileoMobile Project: sharing astronomy with students and teachers around the world

    Science.gov (United States)

    Benitez Herrera, Sandra; Del Sordo, Fabio; Spinelli, Patricia; Ntormousi, Eva

    2015-08-01

    Astronomy is an inspiring tool that can be used to motivate children to learn more about the world, to encourage critical thinking, and engage them in different scientific disciplines. Although many outreach programs bring astronomy to the classroom, most of them act in developed countries and rely heavily on internet connection. This leaves pupils and teachers in remote areas with little access to the latest space missions and the modern astronomical advances. GalileoMobile is an itinerant astronomy education initiative aiming to bridge this gap by donating educational material and organizing activities, experiments and teacher workshops at schools in rural areas. The initiative is run on a voluntary basis by an international team of astronomers, educators, and science communicators, working together to stimulate curiosity and interest in learning, to exchange different visions of the cosmos and to inspire a feeling of unity "under the same sky" between people from different cultures. Since the creation of the project in 2008, we have travelled to Chile, Bolivia, Peru, India, Uganda, Brazil and Colombia, and worked with about 70 schools. From our experiences, we learnt that 1) bringing experts from other countries is very stimulating for children and encourages a collaboration beyond borders; 2) inquiry-based methods are important for making the learning process more effective; 3) involving local educators in our activities helps the longstanding continuation of the project. We are incorporating these lessons learned into a new concept of the project. Constellation 2015, aims to establish a South American network of schools committed to the long-term organisation of astronomical outreach activities amongst their pupils and local communities. Constellation was declared Cosmic Light Project by the International Year of Light 2015 and awarded funding by the OAD. At this Focus Meeting, we will present the outcomes from our latest expeditions in Brazil and Colombia in

  16. Climate Contrarianism: Conspiracies, Movable Goalposts, Cherry Picking, and the Galileo Complex

    Science.gov (United States)

    Somerville, R. C.

    2012-12-01

    independent thinkers and courageous victims of the dominant orthodoxy, reminiscent of Galileo. Understanding the characteristics of scientific contrarianism, and being familiar with its manifestations in many scientific fields, can help to recognize it and to distinguish it from legitimate scientific dissent.

  17. The Galileo Probe: How it Has Changed Our Understanding of Jupiter

    Science.gov (United States)

    Young, Richard E.

    2003-01-01

    The Galileo Mission to Jupiter, which arrived in December of 1995, provided the first study by an orbiter, and the first in-situ sampling via an entry probe, of an outer planet atmosphere. The rationale for an entry probe is that, even from an orbiter, remote sensing of the jovian atmosphere could not adequately retrieve the information desired. This paper provides a current summary of the most significant aspects of the data returned from the Galileo entry probe. As a result of the probe measurements, there has been a reassessment of our understanding of outer planet formation and evolution of the solar system. The primary scientific objective of the Galileo probe was to determine the composition of the jovian atmosphere, which from remote sensing remained either very uncertain, or completely unknown, with respect to several key elements. The probe found that the global He mass fraction is. significantly above the value reported from the Voyager Jupiter flybys but is slightly below the protosolar value, implying that there has been some settling of He to the deep jovian interior. The probe He measurements have also led to a reevaluation of the Voyager He mass fraction for Saturn, which is now determined to be much closer to that of Jupiter. The elements C, N, S, Ar, Kr, Xe were all found to have global abundances approximately 3 times their respective solar abundances. This result has raised a number of fundamental issues with regard to properties of planetesimals and the solar nebula at the time of giant planet formation. Ne, on the other hand, was found to be highly depleted, probably as the result of it being carried along with helium as helium settles towards the deep interior. The global abundance of O was not obtained by the probe because of the influence of local processes at the probe entry site (PES), processes which depleted condensible species, in this case H2O, well below condensation levels. Other condensible species, namely NH3 and H2S, were

  18. Determination of SLR station coordinates on the basis of tracking 45 GNSS satellites: benefits for future ITRF realizations

    Science.gov (United States)

    Sośnica, Krzysztof; Bury, Grzegorz; Zajdel, Radosław; Kaźmierski, Kamil; Drożdżewski, Mateusz

    2017-04-01

    The SLR station coordinates and SLR-derived Earth Rotation Parameters (ERPs) are typically derived on the basis of SLR tracking of four spherical geodetic satellites: two LAGEOS and two Etalons. Between 2014 and 2016, the International Laser Ranging Service (ILRS) initiated four intensive SLR tracking campaigns for Galileo and three campaigns devoted to tracking all GNSS spacecraft. As a result, the number of SLR observations and the number of tracked GNSS satellites have dramatically increased allowing for determining SLR station coordinates and ERPs solely on the basis of SLR tracking of GNSS satellites. This paper shows, for the first time, the solution in which the SLR station coordinates, geocenter motion, and ERPs are determined using the SLR observations to 26 GLONASS, 14 Galileo, 2 BeiDou IGSO, 2 BeiDou MEO, and 1 QZSS satellite. We compare the SLR station coordinate stability derived from GNSS-based results to the LAGEOS-only solution and from a combined 'SLR to GNSS+LAGEOS' solution. We address the issues related to the GNSS orbit determination using sparse SLR data and the issues related to handling range biases in the GNSS solutions. We found that the coordinate stability of those SLR stations which provide a large number of GNSS observations can remarkably be improved. The Length-of-day parameter can be derived from SLR-GNSS solutions with a much better accuracy than from the LAGEOS-only solutions. Finally, we show that the SLR tracking of GNSS satellites improves the consistency between SLR and GNSS solutions, and thus, can be beneficial for the future ITRF realizations.

  19. Mobile satellite communications handbook

    CERN Document Server

    Cochetti, Roger

    2014-01-01

    With a Preface by noted satellite scientist Dr. Ahmad Ghais, the Second Edition reflects the expanded user base for this technology by updating information on historic, current, and planned commercial and military satellite systems and by expanding sections that explain the technology for non-technical professionals.   The book begins with an introduction to satellite communications and goes on to provide an overview of the technologies involved in mobile satellite communications, providing basic introductions to RF Issues, power Issues, link issues and system issues. It describes

  20. Satellite communication antenna technology

    Science.gov (United States)

    Mittra, R. (Editor); Imbriale, W. A. (Editor); Maanders, E. J. (Editor)

    1983-01-01

    A general overview of current technology in the field of communication satellite antennas is presented. Among the topics discussed are: the design of multiple beam systems; frequency reuse; and polarization control of antenna measurements. Consideration is also given to: contour beam synthesis; dual shaped reflector synthesis; beam shaping; and offset reflector design. The applications of the above technologies to present and future generations of communications satellites is considered, with emphasis given to such systems as: the Intelsats; the Defense Satellite Communications System, (DSCS-III); Satellite Business System (SBS), and Comstar.

  1. Methods of satellite oceanography

    Science.gov (United States)

    Stewart, R. H.

    1985-01-01

    The theoretical basis for remote sensing measurements of climate and ocean dynamics is examined. Consideration is given to: the absorption of electromagnetic radiation in the atmosphere; scattering in the atmosphere; and satellite observations using visible light. Consideration is also given to: the theory of radio scatter from the sea; scatter of centimeter waves from the sea; and the theory of operation of synthetic aperture radars. Additional topics include: the coordinate systems of satellite orbits for oceanographic remote sensing applications; the operating features of the major U.S. satellite systems for viewing the ocean; and satellite altimetry.

  2. Geologic map of Io

    Science.gov (United States)

    Williams, David A.; Keszthelyi, Laszlo P.; Crown, David A.; Yff, Jessica A.; Jaeger, Windy L.; Schenk, Paul M.; Geissler, Paul E.; Becker, Tammy L.

    2011-01-01

    Io, discovered by Galileo Galilei on January 7–13, 1610, is the innermost of the four Galilean satellites of the planet Jupiter (Galilei, 1610). It is the most volcanically active object in the Solar System, as recognized by observations from six National Aeronautics and Space Administration (NASA) spacecraft: Voyager 1 (March 1979), Voyager 2 (July 1979), Hubble Space Telescope (1990–present), Galileo (1996–2001), Cassini (December 2000), and New Horizons (February 2007). The lack of impact craters on Io in any spacecraft images at any resolution attests to the high resurfacing rate (1 cm/yr) and the dominant role of active volcanism in shaping its surface. High-temperature hot spots detected by the Galileo Solid-State Imager (SSI), Near-Infrared Mapping Spectrometer (NIMS), and Photopolarimeter-Radiometer (PPR) usually correlate with darkest materials on the surface, suggesting active volcanism. The Voyager flybys obtained complete coverage of Io's subjovian hemisphere at 500 m/pixel to 2 km/pixel, and most of the rest of the satellite at 5–20 km/pixel. Repeated Galileo flybys obtained complementary coverage of Io's antijovian hemisphere at 5 m/pixel to 1.4 km/pixel. Thus, the Voyager and Galileo data sets were merged to enable the characterization of the whole surface of the satellite at a consistent resolution. The United States Geological Survey (USGS) produced a set of four global mosaics of Io in visible wavelengths at a spatial resolution of 1 km/pixel, released in February 2006, which we have used as base maps for this new global geologic map. Much has been learned about Io's volcanism, tectonics, degradation, and interior since the Voyager flybys, primarily during and following the Galileo Mission at Jupiter (December 1995–September 2003), and the results have been summarized in books published after the end of the Galileo Mission. Our mapping incorporates this new understanding to assist in map unit definition and to provide a global synthesis

  3. Snapshot Software Receiver for GNSS in Weak Signal Environments: An Innovative Approach for Galileo E5

    NARCIS (Netherlands)

    Carrasco-Martos, S.; López-Risueño, G.; Jiménez-Baños, D.; Gill, E.K.A.

    2010-01-01

    Global Navigation Satellite System (GNSS) positioning has turned out to be an enabler of Location-Based Services (LBS). This has motivated in recent years an increasing research activity on signal processing techniques for GNSS receivers. However, one main limitation faced by these GNSS receivers is

  4. Snapshot Software Receiver for GNSS in Weak Signal Environments: An Innovative Approach for Galileo E5

    NARCIS (Netherlands)

    Carrasco-Martos, S.; López-Risueño, G.; Jiménez-Baños, D.; Gill, E.K.A.

    2010-01-01

    Global Navigation Satellite System (GNSS) positioning has turned out to be an enabler of Location-Based Services (LBS). This has motivated in recent years an increasing research activity on signal processing techniques for GNSS receivers. However, one main limitation faced by these GNSS receivers is

  5. Satellites of spiral galaxies

    Science.gov (United States)

    Zaritsky, Dennis; Smith, Rodney; Frenk, Carlos; White, Simon D. M.

    1993-01-01

    We present a survey of satellites around a homogeneous set of late-type spirals with luminosity similar to that of the Milky Way. On average, we find fewer than 1.5 satellites per primary, but we argue that we can treat the survey as an ensemble and so derive the properties of the halo of a 'typical' isolated spiral. The projected density profile of the ensemble falls off approximately as 1/r. Within 50 kpc the azimuthal distribution of satellites shows some evidence for the 'Holmberg effect', an excess near the minor axis of the primary; however, at larger projected distances, the distribution appears isotropic. There is a weak but significant correlation between the size of a satellite and its distance from its primary, as expected if satellites are tidally truncated. Neither Hubble type nor spectral characteristics correlate with apparent separation. The ensemble of satellites appears to be rotating at about 30 km/s in the same direction as the galactic disk. Satellites on prograde orbits tend to be brighter than those on retrograde orbits. The typical velocity difference between a satellite and its primary shows no clear dependence either on apparent separation, or on the rotation speed of the primary. Thus our survey demonstrates that isolated spiral galaxies have massive halos that extend to many optical radii.

  6. Communication satellite technology trends

    Science.gov (United States)

    Cuccia, Louis

    1986-01-01

    A chronology of space-Earth interconnectivity is presented. The Advanced Communications Technology Satellite (ACTS) system, Land Mobile Satellite, space-Earth antennas, impact of antenna size on coverage, intersatellite links are outlined. This presentation is represented by graphs and charts only.

  7. Description of the male of Eburella pinima Martins and notes on the geographical distribution of Eburodacrys aenigma Galileo & Martins and Eburodacrys lanei Zajciw (Coleoptera, Cerambycidae

    Directory of Open Access Journals (Sweden)

    Juan Pablo Botero

    2013-12-01

    Full Text Available Description of the male of Eburella pinima Martins and notes on the geographical distribution of Eburodacrys aenigma Galileo & Martins and Eburodacrys lanei Zajciw (Coleoptera, Cerambycidae. The male of Eburella pinima Martins, 1997 is described and illustrated for the first time. Information on Eburodacrys aenigma Galileo & Martins, 2006, previously known only from the female holotype, which lacked locality label, is herein complemented. This species is recorded from Brazil and the male is depicted for the first time. The geographical distribution of Eburodacrys lanei Zajciw, 1958 is further restricted here as some previous records are confirmed to result from misidentifications of E. aenigma.

  8. Large Impact Features on Europa: Results of the Galileo Nominal Mission

    Science.gov (United States)

    Moore, Johnnie N.; Asphaug, E.; Sullivan, R.J.; Klemaszewski, J.E.; Bender, K.C.; Greeley, R.; Geissler, P.E.; McEwen, A.S.; Turtle, E.P.; Phillips, C.B.; Tufts, B.R.; Head, J. W.; Pappalardo, R.T.; Jones, K.B.; Chapman, C.R.; Belton, M.J.S.; Kirk, R.L.; Morrison, D.

    1998-01-01

    The Galileo Orbiter examined several impact features on Europa at considerably better resolution than was possible from Voyager. The new data allow us to describe the morphology and infer the geology of the largest impact features on Europa, which are probes into the crust. We observe two basic types of large impact features: (1) "classic" impact craters that grossly resemble well-preserved lunar craters of similar size but are more topographically subdued (e.g., Pwyll) and (2) very flat circular features that lack the basic topographic structures of impact craters such as raised rims, a central depression, or central peaks, and which largely owe their identification as impact features to the field of secondary craters radially sprayed about them (e.g., Callanish). Our interpretation is that the classic craters (all <30 km diameter) formed entirely within a solid target at least 5 to 10 km thick that exhibited brittle behavior on time scales of the impact events. Some of the classic craters have a more subdued topography than fresh craters of similar size on other icy bodies such as Ganymede and Callisto, probably due to the enhanced viscous relaxation produced by a steeper thermal gradient on Europa. Pedestal ejecta facies on Europa (and Ganymede) may be produced by the relief-flattening movement of plastically deforming but otherwise solid ice that was warm at the time of emplacement. Callanish and Tyre do not appear to be larger and even more viscously relaxed versions of the classic craters; rather they display totally different morphologies such as distinctive textures and a series of large concentric structural rings cutting impact-feature-related materials. Impact simulations suggest that the distinctive morphologies would not be produced by impact into a solid ice target, but may be explained by impact into an ice layer ~10 to 15 km thick overlying a low-viscosity material such as water. The very wide (near antipodal) separation of Callanish and Tyre imply

  9. Bombardment History of the Galilean Satellites and Derived Ages

    Science.gov (United States)

    Neukum, G.; Wagner, R.; Wolf, U.; Head, J. W., III; Pappalardo, R.; Chapman, C. R.; Merline, W.; Belton, M. S.

    1997-07-01

    During the first seven Galileo flybys, high resolution imagery of the three Galilean moons, Europa, Ganymede and Callisto have been obtained. The new imaging data allow to measure crater diameters as small as ~ 100 m. In combination with Voyager data, size-frequency distribution characteristics in the size range of ~ 100 m to ~ 100 km have been determined. Crater distributions show steep slopes (cumulative index about -3) at smaller diameters on each satellite and are shallower at larger diameters, similar to what is seen on the Moon and the asteroids Gaspra and Ida. % % At D = 1 km, crater densities differ by about a factor of 10 between % average dark terrain of Galileo Regio and youngest bright resurfaced areas % on Ganymede. % Crater densities on the most heavily cratered regions on both Ganymede and Callisto are fairly comparable. On Europa, crater densities have turned out to be about a factor of 10 lower than on the youngest bright terrain in the Uruk Sulcus region of Ganymede. The similarity to crater size-frequency distributions found in the inner solar system suggests a similar origin of the projectiles, probably mainly stemming from the asteroid belt, and the impact rate on the Galilean satellites may have had a lunar-like decay with time. Under this assumption, absolute ages may be derived making use of the idea of the ''marker horizon'', i. e. formation of the youngest basins, such as Gilgamesh on Ganymede, about 3.8 b.y. ago. Thus, the most densely cratered dark terrains on both Ganymede and Callisto have likely ages of 4.1 - 4.3 b.y. Basins such as Neith (on Ganymede) or Adlinda (on Callisto) yield likely ages of about 3.9 b.y. Some areas on Europa may be as old as 3 - 3.3 b.y. Other scenarios based on values proposed for the present-day comet impact rate in the Jovian system with non-lunar-like flux time dependences are conceivable and would result in generally younger ages, possibly as young as 10 m.y. These young ages and impact rates for Europa

  10. Beginnings of Satellite Navigation

    Directory of Open Access Journals (Sweden)

    Miljenko Solarić

    2008-05-01

    Full Text Available The first satellite navigation system called the Navy Navigation Satellite System (NNSS or TRANSIT was planned in the USA in 1958. It consisted of 5-6 artificial Earth satellites, was set in motion for the USA military in 1964, and in 1967 for civilian purposes. The frequency shift of received radio waves emitted from the satellite and caused by the Doppler effect was measured. The TRANSIT satellite speed of approaching or moving away was derived from that; the TRANSIT satellites emmited also their own coordinates. Then the ship's position was determined by an intersection of three hyperboloids, which were determined from differences of distances in three time intervals. Maintenance of this navigation system was stopped in 1996, but it is still being used in the USA Navy for exploring the ionosphere. Furthermore, results of Doppler measurements in international projects at the Hvar Observatory from 1982 and 1983. This was the first time in Croatia and the former country that the coordinates of the Hvar Observatory were determined in the unique world coordinate system WGS'72. The paper ends with a brief representation of the Tsiklon Doppler navigation system produced in the former Soviet Union, and there is a list of some of numerous produced and designed satellite navigation systems.Ključne riječi

  11. Do general relativistic effects limit experiments to test the universality of free fall and the weak equivalence principle?

    Science.gov (United States)

    Nobili, Anna M.

    2016-12-01

    The universality of free fall and the weak equivalence principle, which are at the basis of general relativity, have been confirmed to 1 part in 1 013. Space experiments with macroscopic test masses of different composition orbiting Earth inside a low altitude satellite aim to improve this precision by 2 orders of magnitude (with the Microscope satellite launched on April 25, 2016) and up to 4 orders of magnitude (with the Galileo Galilei satellite). At such a high precision, many tiny effects must be taken into account in order to be ruled out as the source of a spurious violation signal. In this work, we investigate the general relativistic effects, including those which involve the rotation of both Earth and the test masses, and show that they are by far too small to be considered even in the most challenging experiment.

  12. Do general relativistic effects limit experiments to test the universality of free fall and the weak equivalence principle?

    CERN Document Server

    Nobili, Anna M

    2016-01-01

    The Universality of Free Fall and the Weak Equivalence Principle, which are at the basis of General Relativity, have been confirmed to 1 part in 10^13. Space experiments with macroscopic test masses of different composition orbiting the Earth inside a low altitude satellite aim at improving this precision by two orders of magnitude (with the Microscope satellite, launched on 25 April 2016) and up to four orders of magnitude (with the 'Galileo Galilei' - GG satellite). At such a high precision many tiny effects must be taken into account in order to be ruled out as the source of a spurious violation signal. In this work we investigate the general relativistic effects, including those which involve the rotation of both the source body and the test masses, and show that they are by far too small to be considered even in the most challenging experiment.

  13. [20th century Galileo? The significance of Freud's life and work, seen in terms of the history of science (lecture on May 6th, 2006)].

    Science.gov (United States)

    Hirschmiüller, Albrecht

    2006-01-01

    This paper gives a sketch of Freud's life and work, discusses the difficulties of reception he met, and, referring to the well-known statement that psychoanalysis represents the third blow to the narcissism of mankind, maintains that, in terms of the history of science, a more meaningful parallel can be drawn between Freud and Galileo than between Freud and Copernicus or Darwin.

  14. Trends In Satellite Communication

    Science.gov (United States)

    Poley, William A.; Stevens, Grady H.; Stevenson, Steven M.; Lekan, Jack; Arth, Clifford H.; Hollansworth, James E.; Miller, Edward F.

    1988-01-01

    Report assesses trends in satellite communication from present to year 2010. Examines restrictions imposed by limited spectrum resource and technology needs created by trends. Personal communications, orbiting switchboards, and videophones foreseen.

  15. Domestic Communication Satellites

    Science.gov (United States)

    Horowitz, Andrew

    1974-01-01

    A discussion of the Federal Communications Commission's new policy on domestic satellites in light of our 1) military and economic history; 2) corporate interests; 3) citizen surveillance; and 4) media control. (HB)

  16. Handbook of satellite applications

    CERN Document Server

    Madry, Scott; Camacho-Lara, Sergio

    2013-01-01

    Top space experts from around the world have collaborated to produce this comprehensive, authoritative, and clearly illustrated reference guide to the fast growing, multi-billion dollar field of satellite applications and space communications. This handbook, done under the auspices of the International Space University based in France, addresses not only system technologies but also examines market dynamics, technical standards and regulatory constraints. The handbook is a completely multi-disciplinary reference book that covers, in an in-depth fashion, the fields of satellite telecommunications, Earth observation, remote sensing, satellite navigation, geographical information systems, and geosynchronous meteorological systems. It covers current practices and designs as well as advanced concepts and future systems. It provides a comparative analysis of the common technologies and design elements for satellite application bus structures, thermal controls, power systems, stabilization techniques, telemetry, com...

  17. Biological satellite Kosmos-936

    Science.gov (United States)

    Vedeshin, L. A.

    1978-01-01

    A description is given of physiological experiments performed on the biological satellite Kosmos-936. Other experiments to determine the electrostatic and dielectric responses to the effects of cosmic radiation are discussed.

  18. Small Satellite Transporter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The primary objective is to determine whether this small satellite transporter is capable of transporting at least four 6U CubeSats is possible for a given set of...

  19. DFH-3 Satellite Platform

    Institute of Scientific and Technical Information of China (English)

    RenShufang

    2005-01-01

    The DFH-3 satellite platform is designed and developed by China Academy of Space Technology (CAST). It is a medium capability communications satellite platform. The platform adopts threeaxis attitude stabilization control system, having solar array output power of 1.7kW by the end of its design lifetime of 8 years. Its mass is 2100kg with payload capacity of 220kg.

  20. The Archimedes satellite system

    Science.gov (United States)

    Taylor, Stuart C.; Shurvinton, William D.

    1992-03-01

    Archimedes is a satellite system conceived by the European Space Agency (ESA) to effectively serve the European market for Mobile Radio Services (MRS). This paper describes the requirements and technical design of the Archimedes satellite system. The underlying assumptions and trade-offs behind the design are detailed and the design is compared and contrasted against alternative design solutions, both technically and economically. A path forward for the development of the system is indicated.

  1. ASTRID II satellit projekt

    DEFF Research Database (Denmark)

    Jørgensen, John Leif; Primdahl, Fritz

    1997-01-01

    The report describes the instruments developed for the Swedish micro satellite "ASTRID II". Specifications of the two instruments realized under this contract, a Stellar Compass and a CSC magnetometer are given follwed by a description of the project status and plan.......The report describes the instruments developed for the Swedish micro satellite "ASTRID II". Specifications of the two instruments realized under this contract, a Stellar Compass and a CSC magnetometer are given follwed by a description of the project status and plan....

  2. Satellite formation. II

    Science.gov (United States)

    Harris, A. W.

    1978-01-01

    A satellite formation model is extended to include evolution of planetary ring material and elliptic orbital motion. In this model the formation of the moon begins at a later time in the growth of the earth, and a significant fraction of the lunar material is processed through a circumterrestrial debris cloud where volatiles might have been lost. Thus, the chemical differences between the earth and moon are more plausibly accounted for. Satellites of the outer planets probably formed in large numbers throughout the growth of those planets. Because of rapid inward evolution of the orbits of small satellites, the present satellite systems represent only satellites formed in the last few percent of the growths of their primaries. The rings of Saturn and Uranus are most plausibly explained as the debris of satellites disrupted within the Roche limit. Because such a ring would collapse onto the planet in the course of any significant further accretion by the planet, the rings must have formed very near or even after the conclusion of accretion.

  3. Hydrated salt minerals on Europa's Surface from the Galileo near-infrared mapping spectrometer (NIMS) investigation

    Science.gov (United States)

    McCord, T.B.; Hansen, G.B.; Matson, D.L.; Johnson, T.V.; Crowley, J.K.; Fanale, F.P.; Carlson, R.W.; Smythe, W.D.; Martin, P.D.; Hibbitts, C.A.; Granahan, J.C.; Ocampo, A.

    1999-01-01

    We reported evidence of heavily hydrated salt minerals present over large areas of Europa's surface from analysis of reflectance spectra returned by the Galileo mission near infrared mapping spectrometer (NIMS) [McCord et al., 1997a, b, 1998a, b]. Here we elaborate on this earlier evidence, present spatial distributions of these minerals, examine alternate water-ice interpretations, expand on our hydrated-salts interpretation, consider salt mineral stability on Europa, and discuss the implications. Extensive well-defined areas on Europa show distinct, asymmetric water-related absorption bands in the 1 to 2.5-??m region. Radiative transfer modeling of water ice involving different particle sizes and layers at Europa temperatures does not reproduce the distinctive Europa water bands. However, ice near its melting temperature, such as in terrestrial environments, does have some characteristics of the Europa spectrum. Alternatively, some classes of heavily hydrated minerals do exhibit such water bands. Among plausible materials, heavily hydrated salt minerals, such as magnesium and sodium sulfates, sodium carbonate and their mixtures, are preferred. All Europa spectral features are present in some salt minerals and a very good match to the Europa spectrum can be achieved by mixing several salt spectra. However, no single or mix of salt mineral spectra from the limited library available has so far been found to perfectly match the Europa spectrum in every detail. The material is concentrated at the lineaments and in chaotic terrain, which are technically disrupted areas on the trailing side. Since the spectrum of the material on Europa is nearly the same everywhere so-far studied, the salt or salt-mixture composition may be nearly uniform. This suggests similar sources and processes over at least a near-hemispheric scale. This would suggest that an extensive subsurface ocean containing dissolved salts is the source, and several possible mechanisms for deposit

  4. Bulk density of asteroid 243 Ida from the orbit of its satellite Dactyl

    Science.gov (United States)

    Belton, M.J.S.; Chapmant, C.R.; Thomas, P.C.; Davies, M.E.; Greenberg, R.; Klaasen, K.; Byrnes, D.; D'Amario, L.; Synnott, S.; Johnson, T.V.; McEwen, A.; Merline, W.J.; Davis, D.R.; Petit, J.-M.; Storrs, A.; Veverka, J.; Zellner, B.

    1995-01-01

    DURING its reconnaissance of the asteroid 243 Ida, the Galileo spacecraft returned images of a second object, 1993(243)1 Dactyl1 - the first confirmed satellite of an asteroid. Sufficient data were obtained on the motion of Dactyl to determine its orbit as a function of Ida's mass. Here we apply statistical and dynamical arguments to constrain the range of possible orbits, and hence the mass of Ida. Combined with the volume of Ida2, this yields a bulk density of 2.6??0.5 g cm-3. Allowing for the uncertainty in the porosity of Ida, this density range is consistent with a bulk chondritic composition, and argues against some (but not all) classes of meteoritic igneous rock types that have been suggested as compositionally representative of S-type asteroids like Ida.

  5. Geodesy and cartography methods of exploration of the outer planetary systems: Galilean satellites and Enceladus

    Science.gov (United States)

    Zubarev, Anatoliy; Kozlova, Natalia; Kokhanov, Alexander; Oberst, Jürgen; Nadezhdina, Irina; Patraty, Vyacheslav; Karachevtseva, Irina

    Introduction. While Galilean satellites have been observed by different spacecrafts, including Pioneer, Voyager-1 and -2, Galileo, New Horizons, and Enceladus by Cassini and Voyager-2, only data from Galileo, Cassini and the two Voyagers are useful for precise mapping [1, 2]. For purposes of future missions to the system of outer planets we have re-computed the control point network of the Io, Ganymede and Enceladus to support spacecraft navigation and coordinate knowledge. Based on the control networks, we have produced global image mosaics and maps. Geodesy approach. For future mission Laplace-P we mainly focused on Ganymede which coverage is nearly complete except for polar areas (which includes multispectral data). However, large differences exist in data resolutions (minimum global resolution: 30 km/pixel). Only few areas enjoy coverage by highest resolution images, so we suggest to obtain regional Digital Elevation Models (DEMs) from stereo images for selected areas. Also using our special software, we provide calculation of illumination conditions of Ganymede surface in various representations [3]. Finally, we propose a careful evaluation of all available data from the previous Voyager and Galileo missions to re-determine geodetic control and rotation model for other Galilean satellites - Callisto and Europe. Mapping. Based on re-calculated control point networks and global mosaics we have prepared new maps for Io, Ganymede and Enceladus [4]. Due to the difference in resolution between the images, which were also taken from different angles relative to the surface, we can prepare only regional high resolution shape models, so for demonstrating of topography and mapping of the satellites we used orthographic projection with different parameters. Our maps, which include roughness calculations based on our GIS technologies [5], will also be an important tool for studies of surface morphology. Conclusions. Updated data collection, including new calculation of

  6. CHINA LAUNCHES NEW SCIENTIFIC SATELLITE

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    China on Sept. 27, 2004 launched a scientific satellite atop a Long March 2D carrier rocket from Jiuquan Satellite Launch Center in Gansu province. 10 minutes after the launch, the satellite entered a preset orbit and is running sound at the orbit. It is the 20th recoverable satellite for scientific and technological

  7. GPS/Galileo Multipath Detection and Mitigation Using Closed-Form Solutions

    Directory of Open Access Journals (Sweden)

    Khaled Rouabah

    2009-01-01

    Full Text Available We propose an efficient method for the detection of Line of Sight (LOS and Multipath (MP signals in global navigation satellite systems (GNSSs which is based on the use of virtual MP mitigation (VMM technique. By using the proposed method, the MP signals' delay and coefficient amplitudes can be efficiently estimated. According to the computer simulation results, it is obvious that our proposed method is a solution for obtaining high performance in the estimation and mitigation of MP signals and thus it results in a high accuracy in GNSS positioning.

  8. Satellite Communications for ATM

    Science.gov (United States)

    Shamma, Mohammed A.

    2003-01-01

    This presentation is an overview on Satellite Communication for the Aeronautical Telecommunication Management (ATM) research. Satellite Communications are being considered by the FAA and NASA as a possible alternative to the present and future ground systems supporting Air Traffic Communications. The international Civil Aviation Organization (ICAO) have in place Standards and Recommended Practices (SARPS) for the Aeronautical Mobile Satellite Services (AMSS) which is mainly derived from the pre-existing Inmarsat service that has been in service since the 1980s. The Working Group A of the Aeronautical Mobile Communication Panel of ICAO has also been investigating SARPS for what is called the Next Generation Satellite Service (NGSS) which conforms less to the Inmarsat based architecture and explores wider options in terms of satellite architectures. Several designs are being proposed by Firms such as Boeing, ESA, NASA that are geared toward full or secondary usage of satellite communications for ATM. Satellite communications for ATM can serve several purposes ranging from primary usage where ground services would play a minimal backup role, to an integrated solution where it will be used to cover services, or areas that are less likely to be supported by the proposed and existing ground infrastructure. Such Integrated roles can include usage of satellite communications for oceanic and remote land areas for example. It also can include relieving the capacity of the ground network by providing broadcast based services of Traffic Information Services messages (TIS-B), or Flight Information Services (FIS-B) which can take a significant portion of the ground system capacity. Additionally, satellite communication can play a backup role to support any needs for ground replacement, or additional needed capacity even after the new digital systems are in place. The additional bandwidth that can be provided via satellite communications can also open the door for many new

  9. Experimental Satellite 2 Successfully Launched

    Institute of Scientific and Technical Information of China (English)

    LiuJie

    2004-01-01

    Small satellite Experimental Satellite 2 (SY-2) was launched by LM-2C launch vehicle from Xichang Satellite Launch Center on Nov. 18, 2004. Later the satellite entered the preset sun-synchronous orbit, which is 700 kilometers above the earth. The launch was the eighthmission this year by China Aerospace Science and Technology Corporation(CASC), which aims to test the technology of the satellite, conduct survey and monitoring of the land and resources and geographical environment on a trial basis.

  10. China's Meteorological Satellite Application System

    Institute of Scientific and Technical Information of China (English)

    Zhang Jiashen

    2008-01-01

    @@ China's meteorological satellite program consists of five systems,namely the satellite system,the launch vehicle system,the launch center system,TT&C and the ground application system.The satellite system consists of FengYun (FY) polar orbiting series and FY geostationary series,which are launched by LM launch vehicles from Taiyan Satellite Launch Center (TSLC) and Xichang Satellite Launch Center (XSLC) respectively.

  11. Design of a Circularly Polarized Galileo E6-Band Textile Antenna by Dedicated Multiobjective Constrained Pareto Optimization

    Directory of Open Access Journals (Sweden)

    Arnaut Dierck

    2015-01-01

    Full Text Available Designing textile antennas for real-life applications requires a design strategy that is able to produce antennas that are optimized over a wide bandwidth for often conflicting characteristics, such as impedance matching, axial ratio, efficiency, and gain, and, moreover, that is able to account for the variations that apply for the characteristics of the unconventional materials used in smart textile systems. In this paper, such a strategy, incorporating a multiobjective constrained Pareto optimization, is presented and applied to the design of a Galileo E6-band antenna with optimal return loss and wide-band axial ratio characteristics. Subsequently, different prototypes of the optimized antenna are fabricated and measured to validate the proposed design strategy.

  12. Research on Simulation in GALILEO Raw Observation Data%GALILEO原始观测数据仿真研究

    Institute of Scientific and Technical Information of China (English)

    王庆; 赵毅; 李传君; 朱超

    2009-01-01

    对GALILEO卫星的运动情况进行了模拟,进而仿真出其全星座卫星系统.分别采用NeQuick模型和Hopfield模型分别对电离层误差和对流层误差进行了模拟.参照GPS对GALILEO卫星钟差和接收机种差进行了模拟.计算各颗GALILEO各卫星的Doppler频移以及对各颗卫星的伪距和载波相位观测值,最后生成RINEX观测文件.生成的观测文件能反应GALILEO观测的实际情况,是进行GALILEO/GPS组合导航以及载波相位模糊度解算等后处理研究的基础.

  13. A study of GPS/Galileo performance in urban environment using a simulation tool

    Science.gov (United States)

    Wu, Falin; Zhang, Kefei; Liu, Gang-Jun

    2006-10-01

    With the rapid development of spatial satellite-based infrastructure in US, Europe, Japan, China and India, there is no doubt that the next generation Global Navigation Satellite Systems (GNSS) will significantly improve the integrity, accuracy, reliability and availability of the position solution. GNSS is becoming an essential element of personal, commercial and public infrastructure and consequently part of our daily lives. However, the applicability of GNSS in supporting a range of location-sensitive applications such as location based services in an urban environment is severely curtailed by the interference of the three-dimensional urban settings. To characterize and gain in-depth understanding of such interferences and to be able to provide location-based optimization alternatives, a high-fidelity three-dimensional urban model is built with large scale high-resolution spatial data sets. The model is then used to support a comprehensive simulation study of current and future GNSS performance, in terms of availability, strength, geometry, positioning accuracy and reliability based on a number of scenarios. Useful time-stamped spatial patterns of the signal performance over the experimental area have been revealed which are very valuable for supporting location based services applications, such as emergency responses, the optimisation of wireless communication infrastructures and car navigation services.

  14. Feedforward Delay Estimators in Adverse Multipath Propagation for Galileo and Modernized GPS Signals

    Directory of Open Access Journals (Sweden)

    Lohan Elena Simona

    2006-01-01

    Full Text Available The estimation with high accuracy of the line-of-sight delay is a prerequisite for all global navigation satellite systems. The delay locked loops and their enhanced variants are the structures of choice for the commercial GNSS receivers, but their performance in severe multipath scenarios is still rather limited. The new satellite positioning system proposals specify higher code-epoch lengths compared to the traditional GPS signal and the use of a new modulation, the binary offset carrier (BOC modulation, which triggers new challenges in the delay tracking stage. We propose and analyze here the use of feedforward delay estimation techniques in order to improve the accuracy of the delay estimation in severe multipath scenarios. First, we give an extensive review of feedforward delay estimation techniques for CDMA signals in fading channels, by taking into account the impact of BOC modulation. Second, we extend the techniques previously proposed by the authors in the context of wideband CDMA delay estimation (e.g., Teager-Kaiser and the projection onto convex sets to the BOC-modulated signals. These techniques are presented as possible alternatives to the feedback tracking loops. A particular attention is on the scenarios with closely spaced paths. We also discuss how these feedforward techniques can be implemented via DSPs.

  15. Evaluation of an automated microplate technique in the Galileo system for ABO and Rh(D) blood grouping.

    Science.gov (United States)

    Xu, Weiyi; Wan, Feng; Lou, Yufeng; Jin, Jiali; Mao, Weilin

    2014-01-01

    A number of automated devices for pretransfusion testing have recently become available. This study evaluated the Immucor Galileo System, a fully automated device based on the microplate hemagglutination technique for ABO/Rh (D) determinations. Routine ABO/Rh typing tests were performed on 13,045 samples using the Immucor automated instruments. Manual tube method was used to resolve ABO forward and reverse grouping discrepancies. D-negative test results were investigated and confirmed manually by the indirect antiglobulin test (IAT). The system rejected 70 tests for sample inadequacy. 87 samples were read as "No-type-determined" due to forward and reverse grouping discrepancies. 25 tests gave these results because of sample hemolysis. After further tests, we found 34 tests were caused by weakened RBC antibodies, 5 tests were attributable to weak A and/or B antigens, 4 tests were due to mixed-field reactions, and 8 tests had high titer cold agglutinin with blood qualifications which react only at temperatures below 34 degrees C. In the remaining 11 cases, irregular RBC antibodies were identified in 9 samples (seven anti-M and two anti-P) and two subgroups were identified in 2 samples (one A1 and one A2) by a reference laboratory. As for D typing, 2 weak D+ samples missed by automated systems gave negative results, but weak-positive reactions were observed in the IAT. The Immucor Galileo System is reliable and suited for ABO and D blood groups, some reasons may cause a discrepancy in ABO/D typing using a fully automated system. It is suggested that standardization of sample collection may improve the performance of the fully automated system.

  16. Global Navigation Satellite Systems (GNSS: The Utmost Interdisciplinary Integrator

    Directory of Open Access Journals (Sweden)

    Bernd Eissfeller

    2015-08-01

    Full Text Available Currently four global satellite navigation systems are under modernization and development: The US American GPS III, the Russian GLONASS, the European Galileo and Chinese BeiDou systems. In the paper the interdisciplinary contributions of different scientific areas to GNSS are assessed. It is outlined that GNSS is not only a technical system but also a basic element of mobile computing high-tech market. At the same time a GNSS has the role of a force enabler in security related applications. Technology, market and security policies are interdependent and are sometimes in a relationship of tension. The goal of the paper is to describe the overall systemics of GNSS from a holistic point of view. The paper also addresses the human factor side of GNSS. The requirements on human resources in GNSS are at least two-fold: On the one hand very specialized engineers are needed; on the other hand the generalists are necessary who are able to understand the system aspects. Decision makers in institutions and industry need special knowledge in technologies, economics and political strategies. Is the current university system able to educate and prepare such generalists? Are specialized master courses for GNSS needed? Are external training courses necessary?

  17. Augmentation of Galileo System to Satellite Navigation Systems%Galileo系统对卫星导航系统的增强作用

    Institute of Scientific and Technical Information of China (English)

    李克昭; 袁建平; 岳晓奎; 朱战霞

    2005-01-01

    介绍了正在建设的Galileo系统,从卫星导航系统的星座、完备性、通讯能力、求解载波相位整周模糊数能力以及对系统轨道漂移影响抑制能力五个方面入手,研究了Galileo系统对空间飞行器导航的增强作用.最后通过仿真研究,进一步分析了Galileo系统在空间飞行器导航应用中的增强作用.

  18. Broadband Incoherent Imaging Using Multiple Aperture Optics

    Science.gov (United States)

    1989-12-01

    objects was by Galileo Galilei in the fall of 1609 (3:30). From that day on, the drive has been to improve upon the quality of the received image...increased diameter. (11:763) A second major drawback is the sheer weight of the mirror. Even Galileo realized that there is a limit to the size of a mirror

  19. Monterey Bay Geoid

    Science.gov (United States)

    1994-03-01

    B.C. (Dragomir et al. 1982) It was from these early studies of the earth’s shape and size that the study of the earth’s gravity began. Galileo Galilei ...feel the earth’s gravitational acceleration but not the centrifugal acceleration. The traditional unit of gravity is the gal, from Galileo , 1 gal - 1

  20. Inter-satellite links: A versatile tool for geodesy and planetary and interplanetary navigation

    Science.gov (United States)

    Schlicht, Anja; Hugentobler, Urs; Hauk, Markus; Murböck, Michael; Pail, Roland

    2016-07-01

    With the use of low-low satellite-to-satellite tracking gravity field recovery made a big step forward. Based on this technique the Gravity Recovery And Climate Experiment (GRACE) mission delivers monthly gravity field with high precision, allowing to measure effects in Earth water storage basins and variations in ice mass in Greenland and Antarctica from space. GRACE is using a Ka-band inter-satellite ranging technique, GRACE Follow-On will in addition test optical ranging. In fundamental physics high-precision optical inter-satellite tracking will be used to detect gravitational waves in space, as a first step LISA Pathfinder was launched recently. Inter-satellite links are not only used for ranging, also data transfer in space is based on such links. ESA's European Data Relay System will be established in up-coming years to collect data from the low orbiting Sentinel satellites and transfer the high data rate to ground. The same link may be used for ranging, data transfer and time transfer, a functionality that is discussed for next generation Galileo satellites. But to exploit this synergy a common concept for all three tasks has to be developed. In this paper we show that with inter-satellite ranging techniques with µm accuracy the limited accuracy of GNSS based orbit determination of low Earth orbiters (LEO), which is due to the limitations of one-way microwave tracking (unsynchronized clocks, phase center variations and offsets of the sending and receiving antennas) can be overcome. In the ESA study GETRIS the following question is answered: How can a highly accurate and precise GEO-based two-way ranging method support GNSS tracking? The reduction of systematic errors in LEO precise orbit determination (POD) by exploiting the synergy between ranging, data- and time-transfer is assessed in a concept consisting of precise two-way GEO-LEO tracking (as used for data transfer) and an ultra-stable oscillator on-board of the geostationary satellite (GEO

  1. Solar Power Satellites

    CERN Document Server

    Flournoy, Don M

    2012-01-01

    Communication satellites are a $144 billion industry. Is there any space-based industry that could possibly beat that market? 'Solar Power Satellites' shows why and how the space satellite industry will soon begin expanding its market from relaying signals to Earth to generating energy in space and delivering it to the ground as electricity. In all industrialized nations, energy demand is growing exponentially. In the developing world, the need for energy is as basic as food and water. The Sun's energy is available everywhere, and it is non-polluting. As business plans demonstrate its technical feasibility, commercial potential, and environmental acceptability, every country on Earth will look to space for the power it needs.

  2. Geostationary satellites collocation

    CERN Document Server

    Li, Hengnian

    2014-01-01

    Geostationary Satellites Collocation aims to find solutions for deploying a safe and reliable collocation control. Focusing on the orbital perturbation analysis, the mathematical foundations for orbit and control of the geostationary satellite are summarized. The mathematical and physical principle of orbital maneuver and collocation strategies for multi geostationary satellites sharing with the same dead band is also stressed. Moreover, the book presents some applications using the above algorithms and mathematical models to help readers master the corrective method for planning station keeping maneuvers. Engineers and scientists in the fields of aerospace technology and space science can benefit from this book. Hengnian Li is the Deputy Director of State Key Laboratory of Astronautic Dynamics, China.

  3. ESA's satellite communications programme

    Science.gov (United States)

    Bartholome, P.

    1985-02-01

    The developmental history, current status, and future plans of the ESA satellite-communications programs are discussed in a general survey and illustrated with network diagrams and maps. Consideration is given to the parallel development of national and European direct-broadcast systems and telecommunications networks, the position of the European space and electronics industries in the growing world market, the impact of technological improvements (both in satellite systems and in ground-based networks), and the technological and commercial advantages of integrated space-terrestrial networks. The needs for a European definition of the precise national and international roles of satellite communications, for maximum speed in implementing such decisions (before the technology becomes obsolete), and for increased cooperation and standardization to assure European equipment manufacturers a reasonable share of the market are stressed.

  4. AVS on satellite

    Science.gov (United States)

    Zhao, Haiwu; Wang, Guozhong; Hou, Gang

    2005-07-01

    AVS is a new digital audio-video coding standard established by China. AVS will be used in digital TV broadcasting and next general optical disk. AVS adopted many digital audio-video coding techniques developed by Chinese company and universities in recent years, it has very low complexity compared to H.264, and AVS will charge very low royalty fee through one-step license including all AVS tools. So AVS is a good and competitive candidate for Chinese DTV and next generation optical disk. In addition, Chinese government has published a plan for satellite TV signal directly to home(DTH) and a telecommunication satellite named as SINO 2 will be launched in 2006. AVS will be also one of the best hopeful candidates of audio-video coding standard on satellite signal transmission.

  5. Satellite Control Laboratory

    DEFF Research Database (Denmark)

    Wisniewski, Rafal; Bak, Thomas

    2001-01-01

    The Satellite Laboratory at the Department of Control Engineering of Aalborg University (SatLab) is a dynamic motion facility designed for analysis and test of micro spacecraft. A unique feature of the laboratory is that it provides a completely gravity-free environment. A test spacecraft...... is suspended on an air bearing, and rotates freely in 3 degrees of freedom. In order to avoid any influence of the gravitational force the centre of mass of the satellite is placed in the geometric centre of the air bearing by an automatic balancing system. The test spacecraft is equipped with a three......-axis magnetometer, three piezoelectric gyros, and four reaction wheels in a tetrahedron configuration. The operation of the spacecraft is fully autonomous. The data flow between the transducers and the onboard computer placed physically outside the satellite is provided by a radio link. The purpose...

  6. GPS satellite surveying

    CERN Document Server

    Leick, Alfred; Tatarnikov, Dmitry

    2015-01-01

    THE MOST COMPREHENSIVE, UP-TO-DATE GUIDE ON GPS TECHNOLOGY FOR SURVEYING Three previous editions have established GPS Satellite Surveying as the definitive industry reference. Now fully updated and expanded to reflect the newest developments in the field, this Fourth Edition features cutting-edge information on GNSS antennas, precise point positioning, real-time relative positioning, lattice reduction, and much more. Expert authors examine additional tools and applications, offering complete coverage of geodetic surveying using satellite technologies. The past decade has seen a major evolut

  7. Declassified intelligence satellite photographs

    Science.gov (United States)

    ,

    1998-01-01

    Recently declassified photographs from spy satellites are an important addition to the record of the Earth?s land surface held by the U.S. Geological Survey (USGS). More than 800,000 high-resolution photos taken between 1959 through 1972 were made available by Executive Order of the President. The collection is held at the USGS EROS Data Center, near Sioux Falls, S. Dak., and are offered for public sale. For some purposes in earth science studies, these photos extend the record of changes in the land surface another decade back in time from the advent of the Landsat earth-observing satellite program.

  8. Oceanography from satellites

    Science.gov (United States)

    Wilson, W. S.

    1981-01-01

    It is pointed out that oceanographers have benefited from the space program mainly through the increased efficiency it has brought to ship operations. For example, the Transit navigation system has enabled oceanographers to compile detailed maps of sea-floor properties and to more accurately locate moored subsurface instrumentation. General descriptions are given of instruments used in satellite observations (altimeter, color scanner, infrared radiometer, microwave radiometer, scatterometer, synthetic aperture radar). It is pointed out that because of the large volume of data that satellite instruments generate, the development of algorithms for converting the data into a form expressed in geophysical units has become especially important.

  9. Satellite oceanography - The instruments

    Science.gov (United States)

    Stewart, R. H.

    1981-01-01

    It is pointed out that no instrument is sensitive to only one oceanographic variable; rather, each responds to a combination of atmospheric and oceanic phenomena. This complicates data interpretation and usually requires that a number of observations, each sensitive to somewhat different phenomena, be combined to provide unambiguous information. The distinction between active and passive instruments is described. A block diagram illustrating the steps necessary to convert data from satellite instruments into oceanographic information is included, as is a diagram illustrating the operation of a radio-frequency radiometer. Attention is also given to the satellites that carry the various oceanographic instruments.

  10. The changing world of global navigation satellite systems

    Science.gov (United States)

    Dow, John M.; Neilan, Ruth E.; Higgins, Matt; Arias, Felicitas

    The world of global navigation satellite systems (GNSS) has been changing very rapidly during the last years. New constellations are being developed in Europe (Galileo), India (IRNSS), Japan (QZNSS) and China (Compass), while both the US GPS and the Russian GLONASS programmes are engaged in very significant mediumto long-term improvements, which will make them even more valuable in the coming years to an ever wider range of civilian users. In addition, powerful regional augmentation systems are becoming (or have already become) operational, providing users with important real time information concerning the integrity of the signals being broadcast by those two systems: these include the US WAAS, the European EGNOS, the Japanese MSAS, the Indian GAGAN and others. Following a number of United Nations sponsored regional workshops, a report by an ad hoc UN "GNSS Action Team" and several preparatory meetings, the International Committee on GNSS (ICG) was established in December 2005 in Vienna, Austria. The ICG is an informal body with the main objective of promoting cooperation on matters of mutual interest related to civil satellite-based positioning, navigation, timing, and value-added services, as well as compatibility and interoperability among the GNSS systems. A further important objective is to encourage the use of GNSS to support sustainable development, particularly in the developing countries. The United Nations Office for Outer Space Affairs (UNOOSA) plays a key role in facilitating the work of the ICG. The members of the Committee are GNSS system providers, while international organisations representing users of GNSS can qualify for participation in the work of the Committee as associate members or observers. The interests of the space geodetic, mapping and timing communities are represented in particular through ICG associate membership of the IGS, IAG, FIG, IERS, while BIPM is an ICG observer. This paper will highlight the background of these developments

  11. Integrated Satellite-HAP Systems

    DEFF Research Database (Denmark)

    Cianca, Ernestina; De Sanctis, Mauro; De Luise, Aldo

    2005-01-01

    for an efficient hybrid terrestrial-satellite communication system. Two integrated HAP-satellite scenarios are presented, in which the HAP is used to overcome some of the shortcomings of satellite- based communications. Moreover, it is shown that the integration of HAPs with satellite systems can be used......Thus far, high-altitude platform (HAP)-based systems have been mainly conceived as an alternative to satellites for complementing the terrestrial network. This article aims to show that HAP should no longer be seen as a competitor technology by investors of satellites, but as a key element...

  12. Satellite orbit determination and gravity field recovery from satellite-to-satellite tracking

    Science.gov (United States)

    Wakker, K. F.; Ambrosius, B. A. C.; Leenman, H.

    1989-07-01

    Studies on satellite-to-satellite tracking (SST) with POPSAT (a geodetic satellite concept) and a ERS-class (Earth observation) satellite, a Satellite-to-Satellite Tracking (SST) gravity mission, and precise gravity field determination methods and mission requirements are reported. The first two studies primarily address the application of SST between the high altitude POPSAT and an ERS-class or GRM (Geopotential Research Mission) satellite to the orbit determination of the latter two satellites. Activities focussed on the determination of the tracking coverage of the lower altitude satellite by ground based tracking systems and by POPSAT, orbit determination error analysis and the determination of the surface forces acting on GRM. The third study surveys principles of SST, uncertainties of existing drag models, effects of direct luni-solar attraction and tides on orbit and the gravity gradient observable. Detailed ARISTOTELES (which replaced POPSAT) orbit determination error analyses were performed for various ground based tracking networks.

  13. Man-made Satellites

    Institute of Scientific and Technical Information of China (English)

    郝昌明

    2005-01-01

    If you watch the sky about an hour after the sun goes down, you may see some “moving stars”. But they're not real stars. They're manmade satellites (卫星). And the biggest of all is the International Space Station (ISS国际空间站).

  14. Observations of artificial satellites

    Directory of Open Access Journals (Sweden)

    A. MAMMANO

    1964-06-01

    Full Text Available The following publication gives the results of photographic
    observations of artificial satellites made at Asiago during the second
    and third year of this programme. The fixed camera technique and that
    with moving film (the latter still in its experimental stage have been used.

  15. Experimental Satellite Quantum Communications.

    Science.gov (United States)

    Vallone, Giuseppe; Bacco, Davide; Dequal, Daniele; Gaiarin, Simone; Luceri, Vincenza; Bianco, Giuseppe; Villoresi, Paolo

    2015-07-24

    Quantum communication (QC), namely, the faithful transmission of generic quantum states, is a key ingredient of quantum information science. Here we demonstrate QC with polarization encoding from space to ground by exploiting satellite corner cube retroreflectors as quantum transmitters in orbit and the Matera Laser Ranging Observatory of the Italian Space Agency in Matera, Italy, as a quantum receiver. The quantum bit error ratio (QBER) has been kept steadily low to a level suitable for several quantum information protocols, as the violation of Bell inequalities or quantum key distribution (QKD). Indeed, by taking data from different satellites, we demonstrate an average value of QBER=4.6% for a total link duration of 85 s. The mean photon number per pulse μ_{sat} leaving the satellites was estimated to be of the order of one. In addition, we propose a fully operational satellite QKD system by exploiting our communication scheme with orbiting retroreflectors equipped with a modulator, a very compact payload. Our scheme paves the way toward the implementation of a QC worldwide network leveraging existing receivers.

  16. Perception via satellite

    Science.gov (United States)

    Robinove, Charles J.

    1970-01-01

    The earth resources observation satellite (EROS) program in the Department of the Interior is intended to gather and use data from satellites and aircraft on natural and man-made features of the earth's surface. Earth resources technology satellite will provide the EROS program with data for use in dealing with natural resource problems and understanding the interaction between man and the environment. Applications will include studies of tectonic features, hydrologic problems, location of fish schools, determination of the conditions of range land, mapping land use for urban planning, studies of erosion and change along coastlines and major streams, and inventories of land use and land forms. In addition, the ERTS data may be used for detecting forest and crop diseases and inventorying crops. The ERTS satellite will be in a polar, sun-synchronous orbit so that each point on the earth's surface will be sensed every 17 to 20 days, at the same time of day. Multispectral photography is being investigated for its usefulness in hydrology. Side-looking airborne radar has not yet been widely used in hydrologic studies, although it is an excellent tool for all-weather, day or night, coverage of large areas. Other techniques being investigated include passive microwave radiometry, ultraviolet and visible stimulated luminescence, and absorption spectroscopy.

  17. Satellite Photometric Error Determination

    Science.gov (United States)

    2015-10-18

    of nearly specular reflections from most solar panels. Our primary purpose in presenting these two plots is to demonstrate the usefulness of...than a transformation for stars because the spectral energy distribution of satellites can change with phase angle and is subject to specular

  18. Creating Better Satellite Conferences.

    Science.gov (United States)

    Horner, Tommy

    1998-01-01

    Presents four ways to improve broadcasts of company satellite conferences, including creative site selection (using facilities at educational institutions rather than hotel rooms); creative programming (using graphics and other interruptions to break up lectures or speeches); creative crew selection; and creative downlink site activities (to…

  19. Ocean surveillance satellites

    Science.gov (United States)

    Laurent, D.

    Soviet and U.S. programs involving satellites for surveillance of ships and submarines are discussed, considering differences in approaches. The Soviet program began with the Cosmos 198 in 1967 and the latest, the Cosmos 1400 series, 15 m long and weighing 5 tons, carry radar for monitoring ships and a nuclear reactor for a power supply. Other Soviet spacecraft carrying passive microwave sensors and ion drives powered by solar panels have recently been detonated in orbit for unknown reasons. It has also been observed that the Soviet satellites are controlled in pairs, with sequential orbital changes for one following the other, and both satellites then overflying the same points. In contrast, U.S. surveillance satellites have been placed in higher orbits, thus placing greater demands on the capabilities of the on-board radar and camera systems. Project White Cloud and the Clipper Bow program are described, noting the continued operation of the White Cloud spacecraft, which are equipped to intercept radio signals from surface ships. Currently, the integrated tactical surveillance system program has completed its study and a decision is expected soon.

  20. OMV With Satellite

    Science.gov (United States)

    1986-01-01

    This 1986 artist's concept shows the Orbital Maneuvering Vehicle (OMV) towing a satellite. As envisioned by Marshall Space Flight Center plarners, the OMV would be a remotely-controlled free-flying space tug which would place, rendezvous, dock, and retrieve orbital payloads.

  1. Advances in satellite oceanography

    Science.gov (United States)

    Brown, O. B.; Cheney, R. E.

    1983-01-01

    Technical advances and recent applications of active and passive satellite remote sensing techniques to the study of oceanic processes are summarized. The general themes include infrared and visible radiometry, active and passive microwave sensors, and buoy location systems. The surface parameters of sea surface temperature, windstream, sea state, altimetry, color, and ice are treated as applicable under each of the general methods.

  2. Defense Meteorological Satellite Program (DMSP)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Defense Meteorological Satellite Program (DMSP) satellites collect visible and infrared cloud imagery as well as monitoring the atmospheric, oceanographic,...

  3. Analysis of L5 phase variations in GPS IIF satellites by the raw observation PPP approach

    Science.gov (United States)

    Liu, Sha; Becker, Matthias

    2015-04-01

    GPS modernization along with Glonass modernization and the emerging Galileo and Compass system has been highly anticipated by every GNSS user since several years. The third civilian L5 signal transmitted by the modernized GPS satellites brings us to the GNSS multi-frequency era. The first GPS IIF satellite was launched in May 2010, until now there are eight block IIF satellites in service and the remaining four IIF satellites are planned to be launched by 2016. The introduction of the third frequency to GPS and the usage of advanced atomic clocks not only provide the users more possibilities but also enable higher positioning accuracy. Nevertheless phase variations are found on the new L5 observation of GPS SVN62. Further investigations suggest that the variations of this satellite are strongly dependent on the satellite inner temperature variation caused by sun illumination. Besides achieving precise positioning accuracy, PPP is also frequently used as a tool to analyze and evaluate various GNSS errors, for instance, tropospheric delays and receiver clock errors. Other than with differential GNSS, it is possible to separate different errors and to identify the error sources with PPP. Conventional PPP is based on the ionosphere-free linear combination, in order to eliminate the first-order ionospheric delays. However only dual frequencies can be used to build ionosphere-free linear combination, which leads to the waste of the information on the third frequency. Furthermore, the frequency dependent errors can not be separated and traced. A new PPP approach that avoids using any linear combination is proposed recently, which is called the raw observation PPP. One advantage of the raw observation PPP approach is that data of all frequencies and all GNSS systems can be jointly used. In addition, the frequency dependent errors are possible to be separated, identified and analyzed. In this paper the raw observation PPP is utilized to analyze the phase variations on L5

  4. DFH Satellite Co.,Ltd.

    Institute of Scientific and Technical Information of China (English)

    SunQing

    2004-01-01

    DFH Satellite Co.,Ltd. is a hi-tech enterprise founded and sponsored by China Aerospace Science and Technology Corporation(CASC) and one of CASC subsidiaries,China Academy of Space Technology (CAST). The company is mainly engaged in the research and development of small satellites and micro-satellites, Osystem designs and product development for satellite application projects as well as the international exchanges and cooperation.

  5. A FOA Estimation Approach for GALILEO/SAR Signal%伽利略搜救信号FOA估计算法

    Institute of Scientific and Technical Information of China (English)

    李瑞; 李集林

    2007-01-01

    GALILEO/SAR系统中,FOA参数的估计精度直接决定着系统的定位精度.对GALILEO/SAR信号的特点进行了分析,在对FFT方法进行阐述的基础上,对Rife和相位差校正法2种频率估计算法进行了分析和仿真,并在此基础上提出了一种综合频率估计算法.该算法结合了上述2种算法的优点,在接收到达信号各频率区间和不同信噪比条件下,都可以满足到达信号频率检测的精度要求.

  6. Analysis the Visible Satellites of Combined GNSS System%组合GNSS系统可见卫星分析

    Institute of Scientific and Technical Information of China (English)

    胡自全; 何秀凤

    2015-01-01

    为解决高山峡谷地区及城市建筑群区域,G PS用户接收到的卫星个数少无法满足定位的最低要求的问题,提出组合GNSS导航定位的方法。利用GPS、GLONASS及GAL‐ILEO系统的卫星轨道参数模拟,计算不同卫星高度角下全球范围内单 GNSS 系统及组合GNSS系统的可见卫星数。研究表明:组合GNSS系统增加了可见卫星数,突破了极端条件下卫星高度角对导航定位的限制,扩展了卫星定位的范围。%In order to solve the problem of the alpine and gorge region and urban built -up area ,the number of satellite receiver to the GPS user cannot meet the minimum require‐ments for the positioning of the small problems ,propose the way of combining of GNSS nav‐igation and positioning .Simulation using GPS ,GLONASS and GALILEO satellite orbit pa‐rameters ,the number of visible satellites are calculated under different satellite elevation an‐gle in the global scope of single GNSS system and GNSS system .Research show s that the combination of GNSS system increase the number of visible satellites ,broke through the limitation of the extreme conditions of satellite elevation angle of navigation and positioning , expanding the scope of satellite positioning .

  7. Telelibrary: Library Services via Satellite.

    Science.gov (United States)

    Liu, Rosa

    1979-01-01

    Investigates the provision of library services via satellite, explains briefly the operation and advantages of communication satellites, and discusses the various telecommunications equipment and services which, when coupled with satellite transmission, will enhance library activities. Demand trend projections for telecommunications services…

  8. Mobile satellite service for Canada

    Science.gov (United States)

    Sward, David

    1988-05-01

    The Mobile Satellite (MSAT) system and a special program designed to provide interim mobile satellite services (IMSS) during the construction phase of MSAT are described. A mobile satellite system is a key element in extending voice and and data telecommunications to all Canadians.

  9. New species of Cerambycinae from the Neotropical Region, and nomen novum for Anelaphus maculatus Galileo, Martins, and Santos-Silva, 2014 (Elaphidiini).

    Science.gov (United States)

    Galileo, Maria Helena M; Martins, Ubirajara R; Santos-Silva, Antonio

    2015-07-17

    Six new species and one new genus are described: Criodion spinosum sp. nov. (Cerambycini), from Bolivia; Eburodacrys wappesi sp. nov. and Eburodacrys skillmani sp. nov. (Eburiini), from Bolivia; Eupempelus rileyorum sp. nov. (Heteropsini) from Panama; Sphalloeme mexicana sp. nov. (Oemini), from Mexico; Wappesoeme camiri sp. nov., new genus (Oemini), from Bolivia. Wappesoeme, Eburodacrys wappesi, E. skillmani, Eupempelus rileyorum, and Criodion spinosum are included in previously published keys. Anelaphus erakyra nomen novum for A. maculatus Galileo et al., 2014 is established.

  10. Satellite Aerodynamics and Density Determination from Satellite Dynamic Response

    Science.gov (United States)

    Karr, G. R.

    1972-01-01

    The aerodynamic drag and lift properties of a satellite are first expressed as a function of two parameters associated with gas-surface interaction at the satellite surface. The dynamic response of the satellite as it passes through the atmosphere is then expressed as a function of the two gas-surface interaction parameters, the atmospheric density, the satellite velocity, and the satellite orientation to the high speed flow. By proper correlation of the observed dynamic response with the changing angle of attack of the satellite, it is found that the two unknown gas-surface interaction parameters can be determined. Once the gas-surface interaction parameters are known, the aerodynamic properties of the satellite at all angles of attack are also determined.

  11. Thematic mapping from satellite imagery

    CERN Document Server

    Denègre, J

    2013-01-01

    Thematic Mapping from Satellite Imagery: A Guidebook discusses methods in producing maps using satellite images. The book is comprised of five chapters; each chapter covers one stage of the process. Chapter 1 tackles the satellite remote sensing imaging and its cartographic significance. Chapter 2 discusses the production processes for extracting information from satellite data. The next chapter covers the methods for combining satellite-derived information with that obtained from conventional sources. Chapter 4 deals with design and semiology for cartographic representation, and Chapter 5 pre

  12. Cooperative and cognitive satellite systems

    CERN Document Server

    Chatzinotas, Symeon; De Gaudenzi, Riccardo

    2015-01-01

    Cooperative and Cognitive Satellite Systems provides a solid overview of the current research in the field of cooperative and cognitive satellite systems, helping users understand how to incorporate state-of-the-art communication techniques in innovative satellite network architectures to enable the next generation of satellite systems. The book is edited and written by top researchers and practitioners in the field, providing a comprehensive explanation of current research that allows users to discover future technologies and their applications, integrate satellite and terrestrial systems

  13. Satellite Control Laboratory

    DEFF Research Database (Denmark)

    Wisniewski, Rafal; Bak, Thomas

    2001-01-01

    The Satellite Laboratory at the Department of Control Engineering of Aalborg University (SatLab) is a dynamic motion facility designed for analysis and test of micro spacecraft. A unique feature of the laboratory is that it provides a completely gravity-free environment. A test spacecraft...... is suspended on an air bearing, and rotates freely in 3 degrees of freedom. In order to avoid any influence of the gravitational force the centre of mass of the satellite is placed in the geometric centre of the air bearing by an automatic balancing system. The test spacecraft is equipped with a three...... of the laboratory is to conduct dynamic tests of the control and attitude determination algorithms during nominal operation and in abnormal conditions. Further it is intended to use SatLab for validation of various algorithms for fault detection, accommodation and supervisory control. Different mission objectives...

  14. Declassified Intelligence Satellite Photographs

    Science.gov (United States)

    ,

    2008-01-01

    Declassified photographs from U.S. intelligence satellites provide an important worldwide addition to the public record of the Earth's land surface. This imagery was released to the National Archives and Records Administration (NARA) and the U.S. Geological Survey (USGS) in accordance with Executive Order 12951 on February 23, 1995. The NARA has the original declassified film and a viewing copy. The USGS has another copy of the film to complement the Landsat archive. The declassified collection involves more than 990,000 photographs taken from 1959 through 1980 and was released on two separate occasions: February 1995 (Declass 1) and September 2002 (Declass 2). The USGS copy is maintained by the Earth Resources Observation and Science (EROS) Center, near Sioux Falls, South Dakota. Both the NARA and EROS provide public access to this unique collection that extends the record of land-surface change back another decade from the advent of the Landsat program that began satellite operations in 1972.

  15. Experimental history: swinging pendulums and melting shellac.

    Science.gov (United States)

    Palmieri, Paolo

    2009-09-01

    Four hundred years ago Galileo Galilei aimed a telescope at the sky. He revolutionized astronomy. Equally revolutionary were his experiments in physics. Unlike his astronomical observations the experiments remain difficult to understand and replicate even today. Two centuries after Galileo, Augustin Coulomb demonstrated experimentally the law of electrostatic force. It has never been successfully replicated. Yet both Galileo and Coulomb were exquisite experimentalists. The fact is that revolutionary experiments in physics are never finished. They are open for investigation for generations to come.

  16. Predictive Network-Centric Intelligence: Toward a Total-Systems Transformation of Analysis and Assessment

    Science.gov (United States)

    2006-09-15

    data are required to bring it to full fruition and prove its superiority to the inevitable legions of doubters. As Galileo Galilei could attest...0 Predictive Network-Centric Intelligence: Toward a Total-Systems Transformation of Analysis and Assessment Winner, 2006 Galileo ...Two previous Galileo papers also have called for the application of scientific method to intelligence assessment: Bruce, James: “Dynamic Adaptation

  17. Satellites in Canadian broadcasting

    Science.gov (United States)

    Siocos, C. A.

    The involvement of Canadian broadcasting and related enterprises in satellite telecommunications is surveyed. This includes point-to-point transmissions and direct ones to the general public. The mode of such utilizations is indicated in both these cases. For the forthcoming DBS systems the many types of service offerings and utilization concepts under discussion elasewhere are presented as well as the business prospects and regulatory climate offering them.

  18. Neptune: Minor Satellites

    Science.gov (United States)

    Murdin, P.

    2003-04-01

    All but one of Neptune's minor satellites orbit within or just outside its ringsystem; the exception is the distant object Nereid. Some of them are betterdescribed as `mid-sized' rather than `minor', but are included under thisheading as little is known of them. The inner four, with approximatediameters, are Naiad (60 km), Thalassa (80 km), Despina (150 km) and Galatea(160 km). The first three lie...

  19. Satellite Surveillance: Domestic Issues

    Science.gov (United States)

    2010-02-01

    earthquake and tsunami in the Indian Ocean and Hurricane Katrina in 2005, when the NGA provided graphics for “relief efforts that depicted the locations of...that show the damage resulting from an earthquake , fire, flood, hurricane, oil spill, or volcanic eruption.8 Bush Administration Policies...Satellite information has continued to have important civil applications in such disparate areas as the movement of glaciers in Yakutat Bay in Alaska

  20. Communications satellites - The experimental years

    Science.gov (United States)

    Edelson, B. I.

    1983-10-01

    Only eight years after the launc of Sputnik-1 by the Soviet Union, the first commercial satellite, 'Early Bird', entered service. In just twelve years commercial satellite service extended around the earth and became profitable. The reasons for the successful development of the communications satellite services in a comparatively short time are considered. These reasons are related to the presence of three ingredients, taking into account technology to create the system, communications requirements to form a market, and a management structure to implement the system. The formation of the concept of using earth orbiting satellites for telecommunications is discussed. It is pointed out that the years from 1958 to 1964 were the true 'experimental years' for satellite communications. The rapid development of technology during this crucial period is described, giving attention to passive satellites, active systems, and development satellites.