ISON entering the sun’s outer plasma atmosphere on 27 Nov 2013 as seen by NASA’s SoHo spacecraft.Reports of Comet ISON’s suicide by sun have been premature. The plucky little nucleus, now thought to be less than a mile across, is streaking closer to its perihelion tomorrow at about 1:37 EDT. The next two days are the time of greatest danger for ISON. If it survives there’s a chance residents in the northern hemisphere will have a clear view of the comet in the first half of December, stretching across as much as a degree or two of arc, as it passes above the earth’s orbital plane at warp speed on its way out of the solar system forever:

Bad Astronomy — The fact that ISON is blooming means it’s getting very bright, probably around magnitude 0.5, about as bright as Mercury as seen from Earth. This is expected, and a good sign! It means gas is pouring off the solid nucleus of the comet and being illuminated by the intense light of the Sun. If it manages to hold itself together, ISON will get even brighter over the next day, and the pictures from SOHO will be spectacular.

Don’t forget: I’ll be participating in a NASA Google+ Hangout Thanksgiving day at 18:00 UTC (I’ll be on at 18:30 for an hour), talking about the comet with several scientists, and showing live images from SOHO and other observatories. Stay tuned to the blog and I’ll have the link and an embedded video so you can watch it live. The Planetary Society also has links where you can get more ISON info, and the Comet ISON Observing Campaign is another great source of news.

I plan to post on this tomorrow and throughout the holiday weekend, providing more viewing info in the hope ISON survives the next few days.