| Discovery | |||||||
|---|---|---|---|---|---|---|---|
| Discovered by | D. C. Jewitt E. Danielson |
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| 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 | 0° | ||||||
| Albedo | 0.05 | ||||||
| Surface temp |
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| 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.