ISON lives! (Sort of!)

Comet ISON as seen after its close approach to the SUn.  (Image credit: ESA/NASA/SOHO/GSFC)

Comet ISON as seen after its close approach to the SUn.  (Image credit: ESA/NASA/SOHO/GSFC)

Yesterday was comet ISON's fateful encounter with our Sun.  So did it live, or has it melted away forever?  Well, um, we're not really sure.  Here's what we know so far.

Sometime around lunchtime in the US yesterday (28 Nov), the comet approached so close to the Sun that it passed behind the coronagraph of the SOHO solar telescipe.  The coronograph is that dark disk you can see in the images above.  It's designed to block out the (extraordinarily bright) disk of the Sun to protect the cameras.  At this time it was lost from view by all observers.  Many telescopes, such as NASA's Solar Dynamics Observatory, never saw the comet again.  SOHO, however, picked the comet back up after it exited the area obscured by the coronograph.  Look at this incredible GIF to see what SOHO has observed.

What we're still not sure of is whether ISON survived this close approach, or whether SOHO has simply picked up the debris field left over after its destruction.  Certainly a significant portion of the comet was disrupted.  NASA's best guess right now is that a small nucleus has survived and that ISON will exit this incredible encounter alive, but a shadow of its former self.

We'll keep you updated as things develop.

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