Astrophoto Friday: Quaoar Discovered

Eight years ago today Caltech astronomers Chad Trujillo and Michael Brown, using Palomar's 48-inch Samuel Oschin Telescope, discovered the object now known as 50000 Quaoar.

Today's Astrophoto Friday image is an animated gif of three discovery images that show Quaoar's motion against the background of the sky.

Quaoar is part of a population of objects that lie out beyond the orbit of Neptune that make up what is known as the Kuiper Belt. The artwork below illustrates the sizes of the largest known worlds of these icy bodies, with a section of Earth at the bottom for scale.


Quaoar has one known moon, Weywot. Studies of Weywot's orbit about Quaoar have led to estimates of its mass an density. Surprisingly, Quaoar has a density more like rock than ice.