Great Images: Dione and Rhea

You might think you are watching daughter cells, as as one planet splits into two.  But what you really see are two of Saturn's moon, Dione and Rhea, passing your sight of vision in their orbits while still very far apart.  Here is the explanation from Discover Magazine:

...the top moon there is Dione, and the bottom one is Rhea. As Cassini flew by them, Dione was closer (a little more than 1.1 million km or about 690,000 miles), and Rhea farther away (1.6 million km or 1 million miles). The angle of Cassini’s trajectory was just right such that Dione passed right in front of Rhea, and it snapped this image just as it happened.