Dia (moon) facts for kids

Dia (also known as S/2000 J 11) is a small moon that orbits the giant planet Jupiter. It is not perfectly round, and it moves in the same direction as Jupiter spins, which is called prograde motion. A team of astronomers led by Scott S. Sheppard found Dia in the year 2000 at the University of Hawaii.

Dia is quite small, only about 4 kilometers (about 2.5 miles) wide. It travels around Jupiter at an average distance of 12,555,000 kilometers (about 7.8 million miles). It takes Dia about 287 Earth days to complete one trip around Jupiter. Its path is tilted by about 28 degrees compared to Jupiter's equator.

Finding Dia: A Tricky Moon

Dia belongs to a group of moons called the Himalia group. These moons are thought to be pieces of a larger asteroid that broke apart a long time ago.

After Dia was first discovered, scientists actually lost track of it for ten years! This happened because its orbit was not known very precisely. It's like trying to follow a tiny bug in a huge field when you don't know exactly where it's going.

Luckily, astronomers were able to find Dia again. This "recovery" helped them figure out its orbit much more accurately. Now, we know much more about where Dia is and where it's going.

Images for kids

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  Dia was photographed by the Canada-France-Hawaii Telescope in December 2001. In the second picture, Dia is hard to see because Jupiter's bright light makes the stars look dimmer.

See also

In Spanish: Dia (satélite) para niños