Nov 30, 15.3 UT: I'm now ready to declare that Comet ISON is "dying"! The past 4 months have been fun, sort of, but I'm looking forward to returning to a normal lifestyle. Whereas comet astronomers are embarrassed by the term "Comet of the Century," they continue to refer to it as a once-in-a-lifetime opportunity to learn about comets. There will be no more updates on this web page for what I will always remember as the "Dud of the Decade.
Nov 30, 04.4 UT: Updated SOHO LASCO C3 animation. The comet seems to be fading
Nov 29, 15.6 UT: The coma and tail are beginning to re-form. We don't know how bright the comet will become, but it's unlikely that it will ever be naked eye visible. Ground-based telescopic observations may be possible starting about December 5.
Nov 28, 21.5 UT:
A remnant of the comet has emerged in C2 images, so the
break-up wasn't complete. Maybe the pieces that remain are exhausted of their volatiles which would explain why there is no coma and only a debris tail.
Nov 28, 20.1 UT: If nothing is seen after 20.9 UT, when the comet should reappear in SOHO LASCO C2 images, then we will be able to conclude that Comet ISON will have disappeared forever.
Nov 28, 19.0 UT: Professionals are commenting on the fact that tail brightness fades toward the nucleus which indicates that the nucleus has either broken-up or has been eroded to nothing. This means the comet will no longer be visible for ground-based observing, and won't be naked eye visible. Karl Battams commented on the double tail, suggesting that the thin tail (above the wider tail below) consists of large pieces of the nucleus that won't be moved by solar light pressure or the solar wind (due to their heavier mass), whereas the wider tail consists of small dust particles that are pushed away from the sun by sunlight pressure. In other words, the thin, bright tail is what's left of the nucleus break-up! Nov 28, 19.2 UT: The lack of any evidence of the comet in the SDO imaging is consistent with a break-up.
Nov 28, 15.5 UT: Whereas yesterday the comet brightened according to SOHO images, today it has faded. Could this be due to the nucleus losing so much material that there's almost nothing left? That's what the pro's are talking about. Nov 28, 18.4 UT: The comet is so far not bright enough to be seen in the SDO images (because SDO doesn't use an occulter disk).
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