Great Image: Dione and Saturn

The image above was taken last December by the Cassini spacecraft. The soft colors of Saturn are a strong contrast with the colorless moon. The European Space Agency provides more details on the photo:

The images used to create this view were obtained with the Cassini-Huygens wide-angle camera at a distance of approximately 603 000 kilometres from Dione through a filter sensitive to wavelengths of ultraviolet light.

Giovanni Domenico Cassini discovered Dione in 1684, it being one of the four moons he identified and named Sidera Lodoicea, or "the stars of Louis," to honor king Louis XIV.  A comparison of Dione to the Earth and its moon is shown below.

Image Credit: NASA/JPL/Space Science Institute

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.