Wait, its alive!!!

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Doc
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Wait, its alive!!!

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http://www.bbc.co.uk/news/science-environment-25143861
Comet Ison destroyed in Sun passage
By Jonathan Amos Science correspondent, BBC News
Soho image Hopes were briefly raised when a dull streak was seen in Soho imagery

Comet Ison was severely battered in its encounter with the Sun, and largely destroyed.

Telescopes saw the giant ball of ice and dust disappear behind the star, but only a dull streamer re-emerge.

Astronomers continued to search for the object, but it eventually became clear that the much vaunted "Comet of the Century" had gone out with a whimper.

Despite its great size, Ison was probably torn apart in the immense heat and tidal forces so close to the Sun.

The European Space Agency's experts on the Soho Sun-watching satellite called the death of the comet at about 21:30 GMT.

"Our Soho scientists have confirmed, Comet Ison is gone," Esa's twitter feed announced.

Ison had captivated skywatchers with its promise ever since it was discovered by Vitali Nevski and Artyom Novichonok in 2012.

A "fresh", 2km-wide object flung in towards the inner Solar System from its home far beyond the outer planet Neptune, it was hoped it might produce a brilliant tail that would arc across the night sky, perhaps for weeks.

And, as it got closer and closer to the Sun, its ices did indeed begin to vaporise, releasing dust that shimmered in a distinctive trailing stream.

But from early on, it was clear Ison was unlikely to be spectacular; it was just not brightening in the way experienced comet watchers had anticipated.

This led scientists to fear for its survival when it eventually grazed past the star at a distance of just 1.2 million km at 18:35 GMT on Thursday.

Soho followed Ison as it began its sweep around the back of the Sun, but then failed to pick up a coherent object at the time it was supposed to re-emerge. A streak in the imagery was interpreted as the last fizzling of debris.

Other telescopes such as Nasa's Solar Dynamics Observatory could detect no clear sign of the comet's nucleus, either.

Passing close to the Sun, Ison would have been subjected to temperatures over 2,000C. And the immense gravity of the star would also have pulled and squeezed on the object as it tumbled end over end.

All the evidence suggests Ison's nucleus was torn apart in the close pass, in the same way that Comet Lovejoy - a previous hopeful in 2011 - was disrupted.

Comets will stay in the news, however. Next year, in October, Comet Siding Spring will breeze past Mars at a distance of little more than 100,000km. And then in November, the European Space Agency's Rosetta mission will attempt to place a probe on the nucleus of Comet 67P/Churyumov-Gerasimenko.
"I fancied myself as some kind of god....It is a sort of disease when you consider yourself some kind of god, the creator of everything, but I feel comfortable about it now since I began to live it out.” -- George Soros
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Doc
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Re: Wait its alive!!!

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http://www.foxnews.com/science/2013/11/ ... encounter/
STOCKHOLM – A comet that gained an earthly following because of its bright tail visible from space was initially declared dead after essentially grazing the sun. Now, there is a silver of hope that Comet ISON may have survived.

New images, basically faint smudges on a screen, being analyzed Friday showed a streak of light moving away from the sun that some said could indicate it wasn't game over just yet.

"It certainly appears as if there is an object there that is emitting material," said Alan Fitzsimmons, an astronomer at Queens University in Belfast, Northern Ireland.

Basically a dirty snowball from the fringes of the solar system, scientists had pronounced Comet ISON dead when it came within 1 million miles (1.6 million kilometers) of the sun Thursday.

Some sky gazers speculated early on that it might become the comet of the century because of its brightness, although expectations dimmed over time. But it wouldn't be all bad news if the 4.5-billion-year-old space rock broke up into pieces, because some scientists say they might be able to study them and learn more about comets.

The European Space Agency, which had declared ISON's death on Twitter late Thursday, was backtracking early Friday, saying the comet "continues to surprise."

Comet ISON was first spotted by a Russian telescope in September last year, and became something of celestial flash in the pan this week for its vivid tail -- visible by the naked eye -- and compelling backstory of impending doom.

The comet was two-thirds of a mile wide as it got within 1 million miles (1.6 million kilometers) of the sun, which in space terms basically means grazing it.

NASA solar physicist Alex Young said Thursday the comet had been expected to show up in images from the Solar Dynamics Observatory spacecraft at around noon eastern time (1700 GMT), but almost four hours later there was "no sign of it whatsoever."

Images from other spacecraft showed a light streak continuing past the sun, but Young said that was most likely a trail of dust continuing in the comet's trajectory.

However, instead of fading, that trail appeared to get brighter Friday, suggesting that "at least some small fraction of ISON has remained in one piece," U.S. Navy solar researcher Karl Battams wrote on his blog. He cautioned that even if there is a solid nucleus, it may not survive for long.

Two years ago, a smaller comet, Lovejoy, grazed the sun and survived, but fell apart a couple of days later.

"This is what makes science interesting," said Fitzsimmons, who specializes in comets and asteroids. "If we knew what was going to happen, it wouldn't be interesting."

ISON's slingshot toward the sun left astronomers puzzled and excited at the same time.

Made up of loosely packed ice and dirt, the space rock came from the Oort cloud, an area of comets and debris on the fringes of the solar system.
"I fancied myself as some kind of god....It is a sort of disease when you consider yourself some kind of god, the creator of everything, but I feel comfortable about it now since I began to live it out.” -- George Soros
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