Discovery of Helike

Helike is a small irregular moon of Jupiter, a few kilometres across, that belongs to the Ananke group. Like the other members, it follows a distant, inclined orbit in the opposite direction to the planet's spin, and astronomers think the group descends from a single captured body that broke apart in a collision. Helike was found in a search for faint outer moons of Jupiter using wide-field cameras on large telescopes in Hawaii. Jupiter's retrograde moons are given names ending in e, and Helike takes its name from a figure of Greek myth connected with Zeus, the counterpart of the Roman god Jupiter.

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