Giovanni Domenico Cassini discovered Saturn’s moon in 1671. And as technology has developed, so have a few mysteries along the way. But one such mystery about Saturn’s moon has been solved.

The Mystery --- The mystery of this moon, called Iapetus, has left astronomers puzzled for years. The moon’s leading side appears to be black, while its back side is always white. When it was discovered by Cassini, he noticed he could always see Iapetus on the western side of Saturn, but never on the eastern side. Because of this strange occurrence, he formed the idea that the moon must be two-toned. There the mystery began.

The Mystery Ends --- Although more research will undoubtedly continue to work out the details, the solution remains simple. The black side of the moon faces the sun the most. And its icy surface is melted, showing its black moon surface beneath. But the white side of the Iapetus remains covered in ice, which explains its snowy white glow.

The Mystery Solver --- The one that solved this mystery is the Cassini-Huygens spacecraft. It captured pictures of Iapetus. Scientists are still studying these photos and other information to gather more ideas and answers about this mysterious moon.