Lysithea (moon)

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Categories: Jupiter's moons | Irregular satellites

**Lysithea**
Discovery
Discovered by	S. B. Nicholson
Discovery date	July 6, 1938^[1]
Orbital characteristics
Mean orbit radius	11,720,000 km^[3]
Eccentricity	0.11^[3]
Orbital period	259.20 d (0.69 a)^[3]
Average orbital speed	3.29 km/s
Inclination	28.30° (to the ecliptic) 25.77° (to Jupiter's equator)^[3]
Satellite of	Jupiter
Physical characteristics
Mean radius	18 km
Surface area	~4100 km²
Volume	~24,400 km³
Mass	6.3×10¹⁶ kg
Mean density	2.6 g/cm³ (assumed)
Equatorial surface gravity	~0.013 m/s² (0.001 g)
Escape velocity	~0.022 km/s
Albedo	0.04 (assumed)
Temperature	~124 K

Lysithea (lye-sith'-ee-ə, IPA: /laɪˈsɪθiə/, or lə-sith'-ee-ə, /lɨˈsɪθiə/; Greek Λυσιθέα) is a prograde irregular satellite of Jupiter. It was discovered by Seth Barnes Nicholson in 1938 at Mount Wilson Observatory^[1] and is named after the mythological Lysithea, daughter of Oceanus and one of Zeus' lovers.^[4]

Lysithea didn't receive its present name until 1975; before then, it was simply known as Jupiter X. It was sometimes called "Demeter"^[5] from 1955 to 1975.

It belongs to the Himalia group, five moons orbiting between 11 and 13 Gm from Jupiter at an inclination of about 28.3°.^[3] Its orbital elements are as of January 2000. They are continuously changing due to Solar and planetary perturbations.

References

^ ^a ^b Nicholson, S.B. (1938). "Two New Satellites of Jupiter". Publications of the Astronomical Society of the Pacific 50: 292–293.
^ [1]
^ ^a ^b ^c ^d ^e Jacobson, R.A. (2000). "The orbits of outer Jovian satellites". Astronomical Journal 120: 2679-2686. doi:10.1086/316817.
^ Marsden, B. G. (7 October 1974). "Satellites of Jupiter". IAUC Circular 2846.
^ Payne-Gaposchkin, Cecilia; Katherine Haramundanis (1970). Introduction to Astronomy. Englewood Cliffs, N.J.: Prentice-Hall. ISBN 0-134-78107-4.

External links

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Moons of Jupiter

Listed in increasing distance from Jupiter. Temporary names in italics.

Inner moons

Metis · Adrastea · Amalthea · Thebe

Galilean moons

Io · Europa · Ganymede · Callisto

Themisto

Himalia group

Leda · Himalia · Lysithea · Elara · S/2000 J 11

Carpo · S/2003 J 12

Ananke group

core	Ananke · Praxidike · Harpalyke · Iocaste · Euanthe · Thyone
peripheral	Euporie · S/2003 J 3 · S/2003 J 18 · Thelxinoe · Helike · Orthosie · S/2003 J 16 · Hermippe · Mneme · S/2003 J 15

Carme group

S/2003 J 17 · S/2003 J 10 · Pasithee · Chaldene · Arche · Isonoe · Erinome · Kale · Aitne · Taygete · S/2003 J 9 · Carme · S/2003 J 5 · S/2003 J 19 · Kalyke · Eukelade · Kallichore

Pasiphaë group