Why Does a Comet Have a Tail? http://ifttt.com/images/no_image_card.png

A comet has two tails. One is a dust tail pushed by light from the sun. Wired Science blogger Rhett Allain uses physics to explain how light can push on matter.



via Wired Top Stories http://feeds.wired.com/~r/wired/index/~3/l2I_lj0Axno/