Before the flyby, experts had made
many
predictions about what might happen to the comet,
ranging from utter disintegration to glorious survival.
No one predicted both.
Karl Battams of NASA's Comet ISON
Observing Campaign says,
"[colleague] Matthew Knight and I are ripping
our hair out right now as we know that so many people
in the public, the media and in science teams want
to know what's happened. We'd love to know that
too! Right now, here's our working hypothesis:
"As comet ISON plunged towards to the Sun,
it began to fall apart, losing not giant fragments
but at least a lot of reasonably sized chunks. There's
evidence of very large dust in the long thin tail
we saw in the [SOHO coronagraph] images. Then, as
ISON plunged through the corona, it continued to
fall apart and vaporize, losing its coma and tail
completely just like sungrazing Comet Lovejoy did
in 2011. What emerged from the Sun was a small but
perhaps somewhat coherent nucleus that has resumed
emitting dust and gas for at least the time being."Battams emphasizes that it is too soon to tell how big the remnant nucleus is or how bright the resurgent comet will ultimately become. "We have a whole new set of unknowns, and this ridiculous, crazy, dynamic and unpredictable object continues to amaze, astound and confuse us to no end. We ask that you please be patient with us for a couple of days as we analyze the data and try to work out what is happening."
Astrophotographer Babak Tafreshi has edited an HD video that compares views of ISON from both of SOHO's coronagraphs. "It seems the comet could become a naked eye object with several degrees of scattered tail by Dec 2nd or 3rd," he predicts. "It's not the comet of the century for sure, and fainter than the Lovejoy sungrazer in Dec. 2011, but an interesting imaging target is just a few nights away!" Solar flare alerts: text, voice
Source:
http://www.spaceweather.com/
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