Jupiter is already the biggest planet in our solar system. It used to be known as the planet with the second-most moons with 80, trailing only Saturn with 83.

Jupiter, the largest planet orbiting the sun, used to be much bigger and stronger when the solar system was just beginning to take shape, a pair of astronomers say. Two scientists at Caltech and ...

But these are not the planet's only celestial tag-alongs. Jupiter has dozens more—and there may still be more to find. In 2003 alone, astronomers identified 23 new moons.