Tuesday, February 24, 2009

Why does Lulin have two tails?

Comet Lulin shows up in photos as having two tails, one in front and the other in back. Some earlier photos have it with a pointy horn sticking out the front. No, it's not a magic unicorn or space narwhal in search of NCC1701 to attack James T. Kirk and kill the nearest red-shirt, but it's just simply a dust tail that is seen from a different point of view. This comet is traveling toward us with the sun about 90 degrees off to the side. The solar wind blows the gas or hydrogen tail directly away from it, while the dust tail is just basically a skid mark left on the path of it's orbit.
This is a good diagram that should explain it well.

No comments: