Ison Update Fragmented Ison serverly spinning out of Control

1) The nucleus of ISON has disrupted into many smaller pieces. It is this cloud of mini-nuclei that continues to sublimate. Rather than a condensed coma we now have a diffuse extended coma that should continues to spread out and fade as individual mini-nuclei move apart (due to variable solar radiation pressure and velocities from the disruption event) and disrupt further. This is what we've seem with other disintegrated comets such as C/1999 S4 (LINEAR) and C/2010 X1 (Elenin). Disruption does not mean the comet disappears instantaneously as the mini-nuclei can last for some days or weeks after disruption. In a way, the comet seems to just fall apart. Based on the SOHO images I've seen this is my guess for what is going on with ISON. 2) Much of ISON's coma consisted on small dust particles that were vaporized by the intense heat of the Sun. We saw something similar with C/2011 W3 (Lovejoy) as pointed out by Joe Marcus, Zdenek Sekanina and Paul Chodas in their papers on the subject. If this is the case with ISON, it should 'regrow' a strong coma and tail as it moves away from the Sun. 3) Phase angles effects are at play. While this could explain the decrease in brightness, it does not explain the smeared appearance of the coma. 4) We are seeing something we've never seen before. John Bortle has mentioned the case of Seki-Lines in 1962. Like ISON, a dynamically new comet that approached to within a few hundredths of an AU of the Sun. Though it was bright prior to and after perihelion, it was not observable at the time of perihelion though it should have been an easy object. It was almost as if the comet turned off near perihelion. Perhaps it was the vaporization of its dust coma by the intense solar heat or something else, but it gives a second example of a comet (with Lovejoy) that seemed to fade out near perihelion only to come back strong afterwards. Time will tell though the continued diffuseness and smeared look of ISON's coma makes me think a significant disruption has occurred. If we're lucky, enough of the nucleus remains in one piece to reform a more substantial coma and tail.



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