Helike (moon) facts for kids
Helike (also called Jupiter XLV) is one of the many moons that orbit the giant planet Jupiter. It was found by a team of astronomers from the University of Hawaii in 2003. The team was led by a scientist named Scott S. Sheppard. When it was first discovered, it was given a special code name: S/2003 J 6.
Facts About Helike
Helike is a small moon, only about 4 kilometers wide. It travels around Jupiter very far away, at an average distance of about 20,540,000 km (that's over 20 million kilometers!). It takes Helike a long time to complete one trip around Jupiter – about 601 Earth days.
Helike's path around Jupiter is not a perfect circle; it's a bit stretched out, which scientists call an orbital eccentricity. Its path is also tilted quite a bit compared to Jupiter's equator, at an angle of about 156 degrees.
How Helike Got Its Name
This moon was officially named Helike in March 2005. Its name comes from Greek mythology. Helike was one of the nymphs (nature spirits) who helped take care of Zeus when he was a baby on the island of Crete. Zeus is the Greek god who is similar to the Roman god Jupiter, which is why the moon of Jupiter was named after her.
Part of a Family: The Ananke Group
Helike is part of a group of moons called the Ananke group. These moons are special because they orbit Jupiter in a "retrograde" direction. This means they go around Jupiter in the opposite direction to how Jupiter spins. They are also not round like Earth's moon; they have irregular, lumpy shapes.
The moons in the Ananke group orbit Jupiter at distances between 19,300,000 km and 22,700,000 km. Their paths are all tilted at similar angles, around 150 degrees.
