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Comet Lovejoy survives boiling brush with Sun, does victory dance

Comet Lovejoy's unlikely trip close to the sun's surface has given scientists a wealth of new information about our sun.

By Elizabeth Barber,?Contributor / June 7, 2013

Comet Lovejoy sails out of the sun's corona in December 2011.

AP/NASA's Solar Dynamics Observatory

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This was not a tale that should have had a happy ending. When Comet Lovejoy sped into the Sun?s corona in 2011, scientists did not expect the daredevil to survive. Astronomers had already tracked 2,000 similar comets making the same inadvisable trip. None had made it, all melting into the sun?s super-hot glow.

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But Lovejoy did live ? and it is now telling scientists new tales about our sun.

"It's absolutely astounding," says Karl Battams, of the Naval Research Lab in Washington DC, in a press release.?"I did not think the comet's icy core was big enough to survive plunging through the several million degree solar corona for close to an hour, but Comet Lovejoy is still with us."

Not only did Lovejoy survive its sunny jaunt ? it began to dance. Or rather, its tail started to wiggle.

Now, in a new paper published in Science, scientists detail what they learned about our sun as they watched the wily comet?s veritable suicide mission.

Comet Lovejoy, known to scientists as C/2011 W3, passed within just 87,000 miles of the sun?s surface for two days in December 2011. When it did, the comet began to evaporate in the sun?s scorch, leaving behind a tail-like trail of material that scientists could observe from multiple perspectives by using five different spacecraft. As the comet?s tail began to wiggle in a seeming victory dance, the scientists fed data from their multiple perspectives on the show into a computer that created a magnetohydrodynamic model of the sun's atmosphere.

Scientists also found the tail?s flits could suggest that the comet was surrounded by plasma waves running through the corona, or that the tail was bouncing on huge magnetic loops in the sun's atmosphere, raising new questions about sun?s atmosphere.

"This is all new," said Battams, in a press release. The new information ?is giving us our first look at comets traveling through the sun's atmosphere. How the two interact is cutting-edge research."

Comet Lovejoy was the discovery of amateur Australian astronomer Terry Lovejoy in December 2011. It belongs to what is known as the Kreutz family of sun-grazing comets, likely all pieces of a single giant comet that splintered apart in 1106 AD. It is thought to be at least 10 times larger than its other family members, and scientists are now pushing that estimate upwards, as only a comet with an unusually large ice core could have come as stunningly near to the sun and survive.

Scientists are unsure how long Lovejoy will exist after this stressful event, and SOHO and NASA's twin STEREO probes are continuing to monitor the comet as it swishes away from the sun

"There is still a possibility that Comet Lovejoy will start to fragment," said Battams, in a press release. "It's been through a tremendously traumatic event; structurally, it could be extremely weak. On the other hand, it could hold itself together and disappear back into the recesses of the solar system."

Thank you for your service, the not-so-little comet that could.

Source: http://rss.csmonitor.com/~r/feeds/science/~3/iuzx6BVoBMA/Comet-Lovejoy-survives-boiling-brush-with-Sun-does-victory-dance

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