S/2003 J 12 facts for kids

S/2003 J 12 is a tiny moon that goes around the giant planet Jupiter. It is one of the smallest moons ever found orbiting Jupiter. Scientists discovered it in 2003.

A team of astronomers from the University of Hawaii found this moon. The team was led by a scientist named Scott S. Sheppard. They used powerful telescopes to spot it.

About S/2003 J 12

This little moon is only about 1 kilometre (or about 0.6 miles) wide. That's roughly the size of a small town! It travels around Jupiter very far away.

Its Orbit Around Jupiter

S/2003 J 12 orbits Jupiter at an average distance of about 17,740,000 kilometres (about 11 million miles). To give you an idea, that's more than 40 times the distance from the Earth to our Moon!

It takes this moon 482.691 days to complete one full trip around Jupiter. That's about one year and four months in Earth time.

The moon's path around Jupiter is also quite tilted. Its inclination is 143 degrees compared to Jupiter's equator. This means it orbits in a very different plane than many other moons.

It also has an orbital eccentricity of 0.4449. This number tells us that its orbit is not a perfect circle. Instead, it's more of an oval shape. This means its distance from Jupiter changes a lot as it travels.

A Unique Moon

S/2003 J 12 is special because it's the closest of Jupiter's faraway moons that orbit backwards. This is called a retrograde orbit. Most moons orbit in the same direction as their planet spins, but retrograde moons go the other way.

Even though it's a retrograde moon, it doesn't seem to belong to any of the known groups of Jupiter's moons. This makes it quite unique among Jupiter's many satellites.

Images for kids

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  Blink animation of S/2003 J 12 in CFHT precovery images from December 2001

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  Recovery images of S/2003 J 12 taken by the CFHT in August 2011

See also

A friendly robot icon.

In Spanish: S/2003 J 12 para niños