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The innermost moon of Jupiter, also known as Jupiter XVI; it is a small object of uneven shape. Together with Adrastea, Metis orbits inside the synchronous orbit radius of Jupiter, which means that it orbits faster than Jupiter rotates on its axis. As a result, its orbit will eventually decay and Metis will fall into the planet. Metis and Adrastea also circle around inside Jupiter's main ring and are undoubtedly the source of the material in this ring.

discovery 1979, by Stephen Synnott
semimajor axis 127,690 km (79,340 miles)
diameter 43 km (27 miles)
mean density 3.0 g/cm3
escape velocity 0.027 km/s (97 km/h, 60 mph)
orbital period 0.295 days (7 h 5 min.)
orbital eccentricity 0.001
orbital inclination 0.000°
visual albedo 0.06

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   • Jupiter, moons

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