Jupiter's Outer Moons

Farthest from Jupiter (outward of the Galilean moons) are the eight tiny moons:

• Leda,
• Himalia,
• Lysithea,
• Elara,
• Ananke,
• Carme,
• Pasiphae and
• Sinope.

Leda

• Leda (Jupiter XIII) is the ninth of Jupiter's known satellites and the smallest:
  • distance from Jupiter: 11,094,000 km
  • diameter: 16 km
  • mass: 5.68e15 kg

• Pronounced "LEE duh"

• Leda was queen of Sparta and the mother, by Zeus in the form of a swan, of Helen and Pollux.

• Discovered by Kowal in 1974.

• Leda, Ananke, and Sinope are among the smallest moons in the solar system.

Pictures

1. (above) Leda discovery image 33k jpg

Himalia

• Himalia (Jupiter VI) is the tenth of Jupiter's known satellites:
  • distance from Jupiter: 11,480,000 km
  • diameter: 186 km
  • mass: 9.56e18 kg

• Pronounced "hih MAL yuh"

• Himalia was a nymph who bore three sons of Zeus (Jupiter).

• Discovered by Perrine in 1904.

• Unlike the inner satellites, the orbits of Leda, Himalia, Lysithea and Elara are significantly inclined to Jupiter's equator (about 28 degrees).

Lysithea

• Lysithea (Jupiter X) is the eleventh of Jupiter's known satellites:
  • distance from Jupiter: 11,720,000 km
  • diameter: 36 km
  • mass: 7.77e16 kg

• Pronounced "ly SITH ee uh"

• Lysithea was a daughter of Oceanus and one of Zeus's lovers.

• Discovered by Nicholson in 1938.

Elara

• Elara (Jupiter VII) is the twelfth of Jupiter's known satellites:
  • distance from Jupiter: 11,737,000 km
  • diameter: 76 km
  • mass: 7.77e17 kg

• Pronounced "EE lar uh"

• Elara was the mother by Zeus of the giant Tityus.

• Discovered by Perrine in 1905.

• Leda, Himalia, Lysithea and Elara may be remnants of a single asteroid that was captured by Jupiter and broken up.

Ananke

• Ananke (Jupiter XII) is the thirteenth of Jupiter's known satellites:
  • distance from Jupiter: 21,200,000 km
  • diameter: 30 km
  • mass: 3.82e16 kg

• Pronounced "a NANG kee"

• Ananke was the mother of Adrastea, by Jupiter.

• Discovered by Nicholson in 1951.

• Ananke, Carme, Pasiphae and Sinope have unusual but similar orbits.

Carme

• Carme (Jupiter XI) is the fourteenth of Jupiter's known satellites:
  • distance from Jupiter: 22,600,000 km
  • diameter: 40 km
  • mass: 9.56e16 kg

• Pronounced "KAR mee"

• Carme was the mother, by Zeus of Britomartis, a Cretan goddess.

• Discovered by Nicholson in 1938.

• Ananke, Carme, Pasiphae and Sinope are especially unusual in that their orbits are retrograde.

Pasiphae

• Pasiphae (Jupiter VIII) is the fifteenth of Jupiter's known satellites:
  • distance from Jupiter: 23,500,000 km
  • diameter: 50 km
  • mass: 1.91e17 kg

• Pronounced "pah SIF ah ee"

• Pasiphae was the wife of Minos and mother, by a white bull, of the Minotaur.

• Discovered by P. Melotte in 1908.

• Ananke, Carme, Pasiphae and Sinope have orbits highly inclined to Jupiter's equator (about 150 degrees).

Sinope

• Sinope (Jupiter IX) is the outermost of Jupiter's known satellites:
  • distance from Jupiter: 23,700,000 km
  • diameter: 36 km
  • mass: 7.77e16 kg

• Pronounced "sah NOH pee"

• Sinope was a woman said to have been unsuccessfully (!) courted by Zeus.

• Discovered by Nicholson in 1914.

• Ananke, Carme, Pasiphae and Sinope may be remnants of a single asteroid that was captured by Jupiter and broken up.

Open Issues

• Why do they fall into two distinct groups? Are they indeed captured asteroids?
• We know next to nothing about these moons. Even the basic mass and size data are not very accurate.