Erinome was discovered on Nov. 23, 2000, by Scott S. Sheppard, David C. Jewitt, Yanga R. Fernandez and Eugene Magnier at the Mauna Kea Observatory in Hawaii.


Erinome is a member of the Carme group, a family of Jovian satellites which have similar orbits and appearance and are therefore thought to have a common origin. The group probably began as a D-type asteroid (possibly from the Hilda family or the Jupiter Trojans) that suffered a collision, which broke off a number of pieces, either before or after being captured by Jupiter's gravity. The largest remaining chunk (still retaining 99% of the group's mass) was named "Carme," and the smaller pieces became the other 16 moons in the Carme group.

All of the Carme moons are retrograde, which means that they orbit Jupiter in the opposite direction from the planet's rotation. Their orbits are also eccentric (elliptical rather than circular) and highly inclined with respect to Jupiter's equatorial plane. They all are very similar in color—light red—except for Kalyke, which is considerably redder than the others. All of these characteristics support the idea that the Carme satellites began as a captured asteroid, rather than forming as part of the original Jupiter system. None of the Carme members is massive enough to pull itself into a sphere, so they are probably all irregularly shaped.

Erinome has a mean radius of about one mile (1.6 km). At a mean distance of about 14.4 million miles (23.2 million km) from Jupiter, the satellite takes about 728 Earth days to complete one orbit.

How Erinome Got its Name

Originally called S/2000 J4, Erinome was named for a chaste young woman in Roman mythology whom Venus causes to fall in love with Jupiter. She loses her virginity to Adonis, however, after Venus throws a fog on her. This displeases the goddess Diana, who turns Erinome into a peacock. Adonis, realizing he has assaulted a love of Jupiter, flees into the woods, but is driven out by Mercury. Just as Adonis is about to defeat Mercury in a violent fight, Jupiter throws a lightning bolt and kills him.

A name ending in "e" was chosen for this moon in accordance with the International Astronomical Union's policy for designating outer moons with retrograde orbits.

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