This NASA photo of the day is absolutely stunning:
What you're seeing are four different moons of Saturn outside of its ice rings (pictured at left). Here's a labelled picture for reference:
Titan is Saturn's largest moon – about 1,600 miles in diameter compared to 1,080 miles for Earth's moon. Here's a composite of the liquid-methane-covered planetoid, as well as an image taken from the surface in 2005:
The icy Dione is Saturn's 4th-largest moon with a diameter of only 700 miles, followed by the tiny moons Pandora and Pan.
Despite the small size of the latter two, they are among several moons that are actually integral in "shepherding" Saturn's rings into their beautiful, uniform shape, as seen in this video:
