Posted on 11/27/2013 9:19:51 AM PST by Repent and Believe
(snip) Comet ISON (C/2012 S1) is nearing the climax...(snip) What will emerge after perihelion into the December dawn? A naked-eye marvel, a binocular-only target for amateur astronomers with good charts, or nothing at all? Maybe the latter, a new report this morning suggests. Michal Drahus posts: (snip)We observe consistent, rapid fading of the molecular emission lines between Nov. 21 and Nov. 25 by at least a factor of 20 (likely more). This may indicate that the nucleus is now at best marginally active or that... it no longer exists.
(snip) I am afraid that there is rather "little hope" for comet C/2012 S1 (ISON). Parent molecules have very short lifetime, thus they are a good approximation of the current activity level of a cometary nucleus. Even if there is no nucleus, we will continue to observe the comet on STEREO images [as in the movie at the top of this page] for a day, two, or even a bit longer.
The comet may even still brighten a bit since it is approaching the Sun, and even a "cloud of dust" will reflect more light in such a situation. But a dramatic decrease in molecules' emission lines while comet is quickly approaching the Sun suggests that the nucleus is no longer active. Too soon to panic, we say, but there are other ominous signs. ISON failed to brighten much as it was disappearing into the dawn a couple of days ago. It gave off a big dust release around the 19th, perhaps hinting of disintegration, followed by less dust production despite the increasing heat. And by the 22nd there were reports that the nucleus's center of brightness was lagging behind its predicted position by about 5 arcseconds, as if most of the light was now coming from trailing rubble. (snip)
(Excerpt) Read more at skyandtelescope.com ...
Right now zero is hoping this comet shines brightly over his white hut and proves the second coming
Looks like ISON is dead. There is always hope....but...
Its rocky core seems to have survived, making it a nice little Earth-crossing asteroid. Should be fun.
http://www.freerepublic.com/focus/news/3096449/posts
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