Comets

Comets originate in the outer solar system. They are small bodies, with a nucleus composed of rock, dust, and ice. They orbit the sun, and often exhibit a coma (or atmosphere) and/or a tail. Their orbits are constantly changing because they are affected by relatively close approaches to the major planets.

Picture Gallery 16 Images over 1 pages.

The orbit of Comet McNaught in 2007 © This image is in the Public Domain.