Sand dunes form some of the most spectacular and dynamic landforms on the planet. Discover how sand dunes are formed and the various types of sand dunes from this new article about sand dunes from Katy Rudolphy.

I frequently receive the question, "What is the radius of the earth?" The radius of the earth varies from a maximum of 3963.14 miles (6378.06 km) at the equator to 3949.9 miles (6356.7 km) at the poles. For related information on the radius of the earth, read my basic earth facts and the size and shape of the earth articles.

In November, the movie 2012 hits theaters. On the Internet, in books, on TV, bus benches, via sky-writers, and everywhere else the hype is growing about the "end of the world" doomsday prophecy scheduled for December 21, 2012. Amanda Briney researched the topic of 2012 and so she brings you a scientific and factual report on the 2012 scenario and what it really means.

A U.S. Census Bureau worker was found dead, hanging from a tree in the Daniel Boone National Forest in rural southeast Kentucky. Bill Sparkman, 51, worked part-time for the Census Bureau. He was found hanging from a tree near a cemetery with the word "Fed" carved in his chest. Law enforcement officials are investigating the case as an apparent homicide but suicide has not yet been ruled out.