Adrastea (original) (raw)

Adrastea

Discovery
Discovered by D. C. Jewitt E. Danielson
Discovered in 1979
Orbital characteristics
Mean radius 129,000 km
Eccentricity 0.0018
Revolution period 7h 9.5m
Inclination 0.05°
Is a satellite of Jupiter
Physical characteristics
Equatorial diameter 23×20×15 km
Surface area km2
Mass 1.8894×1016 kg
Mean density 4.5 g/cm3
Surface gravity 0.012 m/s2
Rotation period 7h 9.5m
Axial tilt
Albedo 0.05
Surface temp minmeanmax KKK
Atmospheric pressure 0 kPa

Adrastea ("a DRAS tee uh") is the second of Jupiter's known moonss (counting outward from the planet). It was discovered by the Voyager 1 probe and is named after the daughter of Jupiter and Ananke (or possibly for Adrastus, the mythical Greek king of Argos who led several expeditions against Thebes and whose daughter married Polynices of Thebes).

Adrastea is inside Jupiter's planetary ring and may be the source of some of its material. Its orbit lies inside Jupiter's synchronous orbit radius, and as a result tidal forces are slowly causing its orbit to decay. It is also within Jupiter's Roche limit, but is small enough to avoid tidal disruption.

This image of Adrastea was taken by Galileo's solid state imaging system between November 1996 and June 1997.