APOD 3.5 Cassini Spacecraft Crosses Saturn's Ring Plane

The Cassini Spacecraft that orbits Saturn has recently taken an image of Saturn's rings edge on. The rings seem to disappear in the image because their width is so small. The rings have a diameter of over 250,000 kilometers, but they are only one kilometer thick. The disappearance of the rings occurs on Earth every 15 years as the rings and our Earth are edge-on. This particular image was taken in February 2005 when the Cassini orbiter was in direct line with the rings. The image uses false colors so you can easily see the rings. In the rings, you can see small bumps that are actually small moons orbiting in the plane of the rings and some of them actually orbit inside of the rings. The shadow of the rings can be seen reflected on the "surface" of Saturn. These shadows can not be seen today due to Saturn's position in its orbit.