Long live ISON!
Comet Ison streaks toward the sun and emerges from its encounter as not much more than a ball of dust. (Source: NASA/STEREO) |Update 10:30 a.m. 11/29/13: As I noted in my first update immediately below, Comet ISON seems to be showing new signs of life. I'm now working on a new post about that. I should be able to publish it by the end of the day, so please check back. In the meantime, a mea culpa: On its closest approach to the sun, ISON really did not seem to have a pulse — but I should have waited before declaring it dead. Although scientists were indeed speaking as if it had met its demise, I should have waited for a more definitive assessment. There is also one other intriguing possibility: Comet ISON may be alive and dead at the same time. For an explanation of that, please come back later today. In the meantime, I've changed the headline on this story. (It had read "Death of Comet ISON Captured by NASA's STEREO Spacecraft.") ||Update 9:30 p.m. 11/28/13: My headline might have been premature! After scientists were declaring ISON dead there's some fleeting evidence that maybe, just possibly, a small, intact chunk of ISON'S nucleus survived. Read about it in Karl Battam's "Schrödinger's Comet" (!!) blog post at the Comet Ison Observing Campaign web site. (Maybe it really is dead and alive at the same time! | This morning, hope was fading as fast as Comet ISON's glow itself — and whatever sliver remained was dashed when it became clear that the traveller from at least 400 billion miles away had disintegrated on its close approach to the sun. You can see it happen in the animation above, consisting of images from NASA's STEREO-A spacecraft. When you watch it, don't blink. ISON streaks toward the sun, circles around it, and emerges as not much more than a ghost of its former self. The comet's nucleus was probably no more than a mile across as it made its fateful approach, and the intense heat of the sun evidently melted all of the ice that had served as a kind of mortar to hold the more solid stuff together. As it whipped around the sun, ISON seems to have been reduced to a hurtling cloud of debris. Here's a stunningly beautiful image of ISON just as it appears to be blinking out:
NASA's SOHO spacecraft captured this image of Comet ISON blinking out as it neared the sun. The disk of the sun is blocked so its glare will not obscure the much fainter comet. The image was posted online by Czech comet watcher Jakub Cerny. Comet Ison, we hardly knew you! But I suspect you taught scientists a thing or two in the past few days — the subject of a future post here at ImaGeo.
