Hostname: page-component-cc8bf7c57-8cnds Total loading time: 0 Render date: 2024-12-12T07:39:39.597Z Has data issue: false hasContentIssue false

Galilean Satellites and the Galileo Space Mission

Published online by Cambridge University Press:  12 April 2016

J.H. Lieske*
Affiliation:
Jet Propulsion Laboratory, California Institute of Technology Pasadena, California, USA

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The Galileo spacecraft arrived at Jupiter in December 1995 to start its two-year mission of exploring the Jovian system. The spacecraft will complete eleven orbits around Jupiter and have ten more close encounters with the outer three Galilean satellites, after the initial close approach to Io on December 7, 1995. Since the Io encounter occurred closer to Io than originally designed, the spacecraft energy change was greater than nominally planned and resulted in an initial spacecraft orbital period about 7 days less than that designed in the nominal tour. A 100-km change in the Io-encounter distance results in an 8-day change in initial period of the spacecraft. Hence the first Ganymede encounter was moved forward one week, and the aim points for the first two Ganymede encounters were altered, but all other encounters would occur on their nominal dates and at the nominal altitudes. This was accomplished without expending spacecraft fuel and resulted in the first Ganymede flyby occurring on June 27, 1996 rather than the nominally scheduled July 4.

Earth- and spacecraft-based data were employed in developing ephemerides in support of the Galileo space mission. An analysis of CCD astrometric observations from 1992–1994, of photographic observations from 1967–1993, of mutual event astrometric data from 1973–1991, of Jovian eclipse timing data from 1652–1983, of Doppler data from 1987–1991, and of optical navigation data from the Voyager spacecraft encounter in 1979, produced the satellite ephemerides for the Galileo space mission.

Type
Dynamics and Astrometry: Present and Future
Copyright
Copyright © Kluwer 1997

References

Aksnes, K. and Franklin, F.: 1976, “Mutual phenomena of the Galilean satellites in 1973”, Astron. J. 81, 464.Google Scholar
Aksnes, K., Franklin, F., Millis, R., Birch, B., Blanco, C., Catalano, S., and Piironen, J.: 1984, “Mutual phenomena of the Galilean and Saturnian satellites in 1973 and 1979/1980”, Astron. J. 89, 28; Astron. J. 89, 1081.Google Scholar
Aksnes, K., Franklin, F., and Magnusson, P.: 1986, “The longitude discrepancy for mutual satellite phenomena resolved”, Astron. J. 92, 1436.Google Scholar
Aksnes, K.: 1993, personal communication.Google Scholar
Byrnes, D.V.: 1996, “Modifying the Galileo tour”, JPL Navigation Team presentation Feb 1996, JPL internal document.Google Scholar
D’Amario, L.A., Byrnes, D.V., Haw, R.J., Kirhofer, W.E., Nicholson, F.T., and Wilson, M.G.: 1995, “Navigation strategy for the Galileo Jupiter encounter and orbital tour”, AAS/AIAA Astrodynamics Specialist Conference, Halifax, Paper 95-381.Google Scholar
Franklin, F., et al. (‘Galilean Satellite Observers’): 1991, “An analysis of the 1985 observations of mutual phenomena of the Galilean satellites”, Astron. J. 102, 806.Google Scholar
Franklin, F.: 1993, personal communication.Google Scholar
Gaskell, R.W.: 1995, personal communication.Google Scholar
Goguen, J.D.: 1994, personal communication.Google Scholar
Kaas, A.A., Franklin, F., Aksnes, K., and Lieske, J.H.: 1996, “Mutual phenomena of the Galilean satellites 1990-1991”, Astron. J., in preparation.Google Scholar
Lieske, J.H.: 1977, “Theory of motion of Jupiter’s Galilean satellites”, Astron. Astrophys. 56, 333.Google Scholar
Lieske, J.H.: 1980, “Improved ephemerides of the Galilean satellites”, Astron. Astrophys. 82, 340 (referred to as E2 ephemerides).Google Scholar
Lieske, J.H.: 1986, “A collection of Galilean satellite eclipse observations 1652-1983: Part II”, Astron. Astrophys., Suppl. Ser. 63, 143.Google Scholar
Lieske, J.H.: 1995a, “Making sense out of 1985 and 1991 mutual events”, Bull. Am. Astron. Soc. 27, 1197.Google Scholar
Lieske, J.H., 1995b, “Galilean satellite ephemerides E5”, JPL Engineering Memorandum 312583 (20 October 1995), JPL internal publication.Google Scholar
Lindegren, L.: 1977, “Meridian observations of planets with a photoelectric multislit micrometer”, Astron. Astrophys. 57, 55.Google Scholar
Lindegren, L.: 1980, “Atmospheric limitations of narrow-field optical astrometry”, Astron. Astrophys. 89, 4147.Google Scholar
Mallama, A.: 1993, “Photrometric models for Galilean satellite astronomy”, J. Geo-phys. Res. 98, 1887318876.Google Scholar
Monet, D.G. and Monet, A.K.B.: 1992, “Galilean satellite astrometry”, U.S. Naval Observatory Flagstaff Station Memorandum.Google Scholar
Ostro, S.J., Campbell, D.B., Simpson, R.A., Hudson, R.S., Chandler, J.F., Rosema, K.D., Shapiro, I.I., Standish, E.M., Winkler, R., Yeomans, D.K., Velez, R., and Goldstein, R.M.: 1992, “Europa, Ganymede, and Callisto: New radar results from Arecibo and Goldstone”, J. Geophys. Res. 97, 18277.Google Scholar
Owen, W.M.: 1995, personal communication.Google Scholar
Pascu, D.: 1977, “Astrometrie techniques for the observation of planetary satellites” in: Planetary Satellites (Burns, J.A., ed.), University of Arizona Press, Tucson, p. 63.Google Scholar
Pascu, D.: 1979, “The Naval observatory program for the astrometrie observation of planetary satellites”, in: Natural and Artificial Satellite Motion (Nacozy, P.E., Ferraz-Mello, S., eds), University of Texas, Austin, p.17. Google Scholar
Pascu, D.: 1993, personal communication.Google Scholar
Pascu, D.: 1994, “An appraisal of the USNO program for photographic astrometry of bright planetary satellites”, in: Galactic and Solar System Optical Astrometry (Morrison, L.V., Gilmor, G.F.e, eds), Cambridge, University Press, p.304. Google Scholar
Pierce, D.A.: 1974, “Observations of Jupiter’s satellites”, JPL Engineering Memorandum 900672.Google Scholar
Pickering, E.C.: 1907, “Eclipses of Jupiter’s satellites”, Harvard Ann. 52, Part I, 1.Google Scholar
Riedel, J.E.: 1994, personal communication.Google Scholar
Synnott, S.P., Donegan, A.J., and Morabito, L.A.: 1982, “Position observations of the Galilean satellites from Voyager data”, JPL internal document.Google Scholar