Journal ArticleDOI
Photometric models for Galilean satellite astronomy
TLDR
In this article, the authors presented tables of photocentric offsets for the Galilean satellites as functions of orbital longitude and solar phase angle, and estimated accuracy of these corrections is 32 km for Io, 45 km for Europa, 49 km for Ganymede, and 40 km for Callisto, but the latter two may be optimistic.Abstract:
Models for the Galilean satellites have been used to determine the distribution of brightness on their surfaces The results indicate that the distance between a satellite's photocenter and its center-of-figure can reach 209 km for Io, 221 km for Europa, 303 km for Ganymede, and 255 km for Callisto Astrometry of the satellites can achieve much greater precision than this, so a correction for the photocentric offset should be applied This paper presents tables of photocentric offsets for the Galilean satellites as functions of orbital longitude and solar phase angle The estimated accuracy of these corrections is 32 km for Io, 45 km for Europa, 49 km for Ganymede, and 40 km for Callisto, but the latter two may be optimistic The satellite ephemerides derived from astrometry are essential for interpreting observations of variable phenomena on Io, such as volcanic activity inferred from IR observations taken during occultations of the satellite Accurate ephemerides are also critical to spacecraft navigationread more
Citations
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Journal ArticleDOI
The Radius of Jupiter and Its Polar Haze
TL;DR: In this article, CCD photometry of Jupiter's satellite Callisto in eclipse has been fitted to model light curves to determine polar radii of 67,168±50 km (north) and 67,106±62 km (south).
Journal ArticleDOI
Precise timings of Galilean satellite eclipses and assessment of the E-3 ephemeris
Anthony Mallama,Douglas S. Caprette,Peter Nelson,James L Park,Donald F. Collins,Michal Vojtisek-Lom +5 more
TL;DR: Astrometric positions for the Galilean satellites are derived from high-precision timings of their jovian eclipses observed with CCD cameras between 1990 to 1993, and the positions are compared to Lieske's E-3 ephemeris as mentioned in this paper.
Journal ArticleDOI
Jovian satellite positions from Hubble Space Telescope images
TL;DR: In this article, an accurate technique has been developed for measuring planetocentric positions of Jupiter's satellites from Wide Field/Planetary Camera images using a model ellipse generated from the physical ephemeris of the planet including its phase defect.
Journal ArticleDOI
Astrometric CCD observations of the inner Jovian satellites in 1999-2000
TL;DR: In this article, the inner positions of the inner Jovian satellites Thebe, Amalthea, Adrastea and Metis are compared with theoretical ones, and the dependence of the differences of the observed and calculated positions on the orbital longitude is presented for their observations.
Journal ArticleDOI
Observational detection of eclipses of J5 Amalthea by the Galilean satellites
Apostolos A. Christou,Fraser Lewis,Fraser Lewis,Fraser Lewis,Paul Roche,Paul Roche,Paul Roche,M. G. Hidas,M. G. Hidas,Timothy M. Brown,Timothy M. Brown +10 more
TL;DR: In this paper, the authors carried out observations of the small jovian satellite Amalthea (J5) as it was being eclipsed by the Galilean satellites near the 2009 equinox of Jupiter in order to apply the technique of mutual event photometry to the astrometric determination of this satellite's position.
References
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Journal ArticleDOI
Voyager photometry of Europa
Bonnie J. Buratti,Joseph Veverka +1 more
TL;DR: In this paper, the authors derived the photometric properties of Europa using a linear superposition of a lunar-like scattering law and a Lambert component, which is an adequate simple representation of the scattering properties.
Journal ArticleDOI
Four-color photometry of the Galilean satellites
TL;DR: In this article, the rotational light curves for Io, Europa, and Ganymede at a mean phase angle of about 6 degrees were obtained by combining their observations with photometry obtained by others over a broader range of phase angles.
Journal ArticleDOI
Color photometry of surface features on Ganymede and Callisto
Steven W. Squyres,Joseph Veverka +1 more
TL;DR: In this article, the photometric properties of selected surface features on Ganymede and Callisto are studied, using Voyager images over phase angles from 10 to 124 deg, taken with a clear filter (effective wavelength of approximately 0.5 microns).
Journal ArticleDOI
Ganymede and Callisto - Surface textural dichotomies and photometric analysis
TL;DR: In this paper, complete solar phase curves of the Ganymede and Callisto leading and trailing hemispheres are obtained by reducing Voyager imaging observations and combining them with ground-based telescopic data, in order to derive hemispherical values of the single scattering albedo, the single particle phase function (SPPF), the compaction state (CS) of the optically active portion of the regolith, and the mean slope angle of macroscopic features.