[AZ-Observing] Changes in 17P/Holmes in Six Hours

My earlier notes for the comet were taken at around 5:30 UT on the 25th.  I 
just took a look at 11:30 UT.  There have been some changes.

Earlier, I would have put the brightness at only a couple tenths brighter than 
Delta Persei, or 2.8.  Now I have it as not quite midway between Delta and 
Alpha Persei, which puts it at 2.5, or maybe 2.4.

Through the scope, I have been comparing its by using two 10th (?) magnitude 
stars within a few arcminutes.  In the earlier view, it was located between 
these two stars, but has now moved off of this line.  Earlier, I could line up 
5 shells between the stars; now I would say that value is closer to 3.  So that 
shell has grown by between 50 and 100%.  It's late (or early), so I am hoping 
that these are the same two stars, and I'm not just too tired to make a good 
observation.

Finally, the fainter "outer halo" that has been mentioned appears to be more 
easily visible.  The moon's altitude is quite a bit lower, so that could be 
helping sky brightness.  I don't see anything but a spherical form to this 
halo, and have not picked up any elongation or faint tail structure throughout 
the night.

Here's one case where it would be nice to live at a more northerly latitude, 
where the night would last longer.  But then again, there can't possibly be 
more comfortable observing weather than what currently exists in southern 
Arizona.

Tom
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