A green-tinged comet is now buzzing by Earth, and the best chance to see this space oddball might be Monday night.
Comet Lulin, first discovered by a Chinese teenager just over a year ago, is making its possibly first and last flyby of Earth this month, traveling from the farthest edges of the solar system about 18 trillion miles away.
Stargazers with binoculars or a telescope could get a pretty good glimpse of the frozen ball of ice and dust hurtling across the night sky. To the naked eye, however, Lulin might only look like a dim, fuzzy star.
"While comets are notoriously unpredictable, it is estimated that it should be bright enough to be seen by the naked eye after mid-month, if you are under a dark sky," said Erika Gibb, assistant professor of physics and astronomy at the University of Missouri-St. Louis. "It is gradually getting higher in the sky, so that it will rise around midnight near Feb. 24. After that, it will continue along its path in the sky, getting fainter as it heads to the outer solar system."
Lulin gets its green color from the gases that make up its atmosphere, namely diatomic carbon and cyanogen, a poisonous gas found in many comets.
"When sun shines on these molecules, they glow," Gibb said. "Cyanogen glows green. I think it's important to mention that this gas doesn't pose a problem for us. When we went through the tail of Halley's comet, a lot of people worried they were going to die from poison gas."
A NASA satellite utilizing X-rays show the comet is quite active, shedding more than 800 gallons of water per second as it moves closer to the sun.
Lulin will fade out of view by mid-March when it moves to the dark depths of the outer solar system.
Around midnight Monday night, the comet will be as close to Earth as it will ever get. But don't worry, we won't get grazed. Lulin will still be 38 million miles away
To check out the comet, first find Saturn and then look south, or slightly southwest.
If you can't wait until then, check out some images captured by amateur astronomer Gregg Ruppel of St. Louis that are being widely circulated in astronomy circles. His Web site is located at:
More information: www.ruppel.darkhorizons.org/comet_lulin.htm
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