Cassini that is on the orbit of Saturn, will fly by the Iapetus moon on 10th. of September. The closest distance will be only 1640 kilometers, which means we will probably see high quality close-up pictures of the moon. What makes the moon interesting is its difference in brightness. The scientists are eager to figure out the reason for such difference. Another very interesting thing in Iapetus is the belt of high mountains in its equator.Read more about Cassini in Nasa’s site.

Picture borrowed from Wikipedia.