Partial Solar Eclipse

Today, much of the western United States got to see a partial solar eclipse.  For some lucky observers, they got to see an annular eclipse (where the silhouette of the moon was completely centered in the sun).  Here in Fort Collins, it was "only" partial - but pretty spectacularly partial (up to 85% obscured).  Unfortunately for me, the clouds completely eclipsed the maximum eclipse.  However, I got a nice sequence of the rest of it up until sunset.  This is a composite of images taken roughly every 5 minutes during the eclipse.

Edit - here is an edited version to bring out the contrast a little better.  Note the limb-darkening of the Sun versus the very sharp edge of the Moon.




The sharp-eyed might note that there is a stray "sun spot" on one of the images.  It is a bird who flew through during the exposure...

Notes - this series was taken with a Canon EOS 5D Mk II camera - most exposures were 1/1000 sec at ISO 400.  The camera was attached to a 1000 mm f/10 Schmidt-Cassegrain telescope with a solar filter on the front.

Edit - below is the original version of this composite.



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