This evening, February 24th, Comet Lulin will pass by Earth at its closest point during its maiden voyage through the inner solar system. Viewers will be able to see the viridian-hued visitor near the constellation Leo, in the southeastern sky.
Lulin’s colors come from the cyanogen gases in its atmosphere. These are ionized by the radiation from the sun (similar to what makes the northern lights glow) and emit a green color. It has both a tail and an “anti-tail”….a trail of particles blown out both behind it and in front.
Lulin was discovered in 2007 at Lulin Observatory in Taiwan. It travels in a retrograde orbit around the sun, opposite from the planets and most other bodies in the solar system. Its trajectory brings it within 38 million miles of Earth on February 24, which is about 14.5 times the distance from Earth to the Moon but still much closer than our neighbor Mars.
Amateur astronomers have been watching this comet during its approach the past few weeks. The photo above was taken by Gregg Ruppel in St. Louis on Feb. 6…see more great shots of Lulin and other lights in the dark on his website. Thanks for all your work Gregg!
UPDATE 2/24/09 11:13 PM CST: Meh. Too bright here to see anything. I’ll have to look for pics from those in less light-polluted locations. Have any good photos of Lulin? Send them to firstname.lastname@example.org and I’ll post them with credits. – J
UPDATE 2/26/09: For those of you who, like myself, live in urban environments where the night sky is a dull brown glow dotted by ten or twelve stars at best and to whom a viewing of Comet Lulin would consist of an airplane ticket to a remote location, here’s some photos taken by viewers around the world on spaceweather.com’s dedicated Lulin page. Really beautiful stuff. This comet turned out to be quite a looker.