More and more Moons of Jupiter
News story originally written on March 20, 2003

Jupiter and its four largest moons. Click on image for full size (32K JPEG) Image courtesy NASA

Astronomers have discovered a dozen new moons of Jupiter so far in 2003. Scott Sheppard and David Jewitt of the University of Hawaii and Jan Kleyna of Cambridge University led the team of astronomers who discovered the new moons. Jupiter now has a total of 52 known moons. All of the new moons are very small, ranging between one and four kilometers in diameter. They all orbit Jupiter in the direction opposite Jupiter's rotation; such orbits are called retrograde.

The moons were discovered using telescopes on the top of the volcano Mauna Kea in Hawaii. For now, the moons all have temporary names. They are called S/2003 J1 through S/2003 J12 ("S" for satellite; "2003" for the year they were discovered; "J" means they are moons of Jupiter; and the 1 through 12 at the end indicates the order each was discovered). Later the moons will be given "real" names. Astronomers think there may be as many as 100 moons with a diameter of one kilometer or greater orbiting Jupiter! Jupiter, the largest planet in our Solar System, has more known moons than any other planet.

Jupiter and its four largest moons. Click on image for full size (32K JPEG) Image courtesy NASA

Astronomers have discovered twelve new moons of Jupiter so far in 2003. Jupiter now has a total of 52 moons that we know of. Jupiter, the largest planet in our Solar System, has more moons than any other planet. Astronomers think there may be as many as 100 small moons orbiting Jupiter! So we may discover many more moons around Jupiter in the future.

For now, the moons all have temporary names. They are called S/2003 J1 through S/2003 J12. Later the moons will be given "real" names.

All of the new moons are very small. They are between one and four kilometers in diameter. The moons were discovered using telescopes on the top of a volcano called Mauna Kea in Hawaii.

Jupiter and its four largest moons. Click on image for full size (32K JPEG) Image courtesy NASA

Astronomers have discovered twelve new moons of Jupiter so far this year. Jupiter is the largest planet in our Solar System. It has more moons than any other planet. Jupiter has 52 moons that we know about.

All of the new moons are very small. The biggest ones are only about four kilometers (about two and one-half miles) across. You could walk all the way around them in a day or two!

The moons were discovered using telescopes on the top of a volcano in Hawaii.