Agreed that the whites are blown out. I had a couple of thousand shots taken from a photo drive from Fairbanks to Seattle and I've gone through most of them with the exception of some bison and caribou shots, but I haven't done any careful finishing on them, which I don't worry about till I actually choose something to print. With my workflow like that sometimes I end up with an aurora post that has a minor pano-overlap mistake or a small blown out area here or there. The original is raw of course and it does have enough headroom that I'll be able to recover the blown area.
Here's another from the same period (last week, Nov 08).
That's a pretty baldy too! Whites are a bit hot but a good catch for both of you 
(the whites are hot)