Metis (moon)

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Metis

Image of Metis was taken by Galileo's solid state imaging system between November 1996 and June 1997.
Discovery
Discovered by	S. Synnott
Discovered on	March 4, 1979
Orbital characteristics
Mean radius	127,691 km (0.000854 AU)
Eccentricity	0.0012
Periapsis	127,540 km (0.000853 AU)
Apoapsis	127,840 km (0.000855 AU)
Revolution period	0.294780 d (7 h 4.5 min)
Orbital circumference	802,300 km (0.005 AU)
Orbital velocity	max: 31.539 km/s mean: 31.501 km/s min: 31.464 km/s
Inclination	2.22° (to the ecliptic) 0.00° (to Jupiter's equator)
Is a satellite of	Jupiter
Physical characteristics
Mean diameter	43 km
Surface area	~5800 km2
Volume	~41,600 km3
Mass	1.2×1017 kg
Mean density	3.0 g/cm3
Surface gravity	0.016 m/s2 (0.002 g)
Escape velocity	0.027 km/s
Rotation period	synchronous
Rotation velocity	19 km/h
Axial tilt	zero
Albedo	0.06
Surface temp.	min mean max K ~123 K K
Atmospheric pressure	0 kPa

Metis (mee'-təs, IPA: [ˈmiːtəs], Greek Μήτις), or Jupiter XVI, is the innermost member of the Jupiter's small inner moons and thus Jupiter's innermost moon.

The moon was discovered in 1979 by the Voyager 1 probe and was designated S/1979 J 3. In 1983 it was officially named after the mythological Metis, a Titaness who was the first wife of Zeus and the mother of Athena.

Metis lies within Jupiter's main planetary ring, and may be the source of the material that comprises it. Its orbit lies inside Jupiter's synchronous orbit radius (as does Adrastea's), and as a result, tidal forces are slowly causing its orbit to decay. It is also within its density's fluid Roche limit, but not its rigid Roche limit, and so avoids tidal disruption.

Metis, the moon of Jupiter, is not to be confused with the asteroid 9 Metis.

[edit] See also

• Inner satellite

edit Jupiter's natural satellites
Inner satellites | Galilean moons | Themisto | Himalia group | Carpo | S/2003 J 12 | Ananke group | Carme group | Pasiphaë group | S/2003 J 2
See also: Pronunciation key | Rings of Jupiter