Reference Pages
15 November 2010, 01:06 PM ET
Stars are giant, luminous spheres of plasma. offers an overview of stars, including their formation, observation, classification and naming designations.
15 November 2010, 12:59 PM ET
The sun is at the heart of our solar system and 8 planets orbit the sun. Also part of the solar system is the asteroid belt, trans-neptunian region and dwarf planets. Learn more at
15 November 2010, 12:49 PM ET
Earth is the only planet known to support life. Learn about Earth science facts and the planet’s interior composition, surface and atmosphere.
09 November 2010, 11:23 AM ET
The Eighth Planet is an Ice Giant
04 May 2009, 08:44 AM ET
When stars can't handle their nuclear fuel, they explode in a brilliant burst of light.
03 August 2007, 10:45 AM ET