The annual (almost) winter solstcie sunset trip

Several years ago my friend Dean Ketelsen carefully scouted the Catalina Highway to identify a location from which he could take a picture of the Sun setting behind Kitt Peak National Observatory, some 60 miles distant.  Dean maintains an excellent blog and I highly recommend visiting-  In addition to being a knowledgeable amateur astronomer, his professional career has led him to work at the Steward Observatory Mirror Lab, where among other projects they fabricate the largest telescope mirrors in the world.  His blog often features work from the lab, such as this post yesterday.

Each year Dean organizes a trip up to the spot on the Catalina Highway to observe and take pictures of the Sun as it sets behind Kitt Peak- and it does this very near the winter solstice.  Approximately 3 days before solstice the alignment is favorable, and again 3 days following the solstice just as the Sun is again trekking northward in our sky.  I have done this trip a few times in the past and you can read about these adventures on my blog from 2013 (my favorite images), 2012, and I even attempted a time-lapse in 2013.

This year I headed up with Dean and a few others on Thursday, December 17th and set up with my TEC 140 triplet refractor, Solar Prism (i.e. Herschel Wedge) Canon 6D DSLR.  I focused on the Sun in advance and had the mount tracking as the Sun moved towards the Horizon.  I had planned to try another time-lapse but unfortunately I forgot to turn off the tracking on the mount until halfway through sunset- so instead of seeing the sunset, the time-lapse would have shown Kitt Peak rising. First, a single shot of the Sun taken just after set-up with addition of a 1.6x Barlow lens (a converter).

Below is a single shot from the moment when all the structures atop Kitt Peak were illuminated by the Sun.  Note the green rim on the upper limb of the Sun caused by refraction of the sunlight through the Earth's atmosphere.

As always, click the above images to enlarge them and finally, Happy New Year to all!