Lysithea (moon)

Lysithea is a prograde irregular satellite of Jupiter. It was discovered by Seth Barnes Nicholson at Mount Wilson Observatory in 1938 and is named after Lysithea, a daughter of Oceanus and one of Zeus' lovers in Greek mythology.

Lysithea belongs to the Himalia group, a cluster of small moons orbiting Jupiter at a distance of roughly 11.1 to 11.7 million kilometers with inclinations of approximately 27.5°. Lysithea is one of the larger members of this group.

Lysithea has an average radius of about 18 kilometers, making it roughly the same size as Leda. Its surface is very dark, reflecting only about 4% of the light that hits it (albedo of 0.04).

The orbital elements of Lysithea are constantly changing due to solar and planetary perturbations. It orbits Jupiter in approximately 259 days.

Prior to its official naming in 1975, Lysithea was simply referred to as Jupiter X.