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We got there a little before sunset, and drove up "Rhyolite Canyon" along some beautiful scenery. Fall colors were a little past peak among the sycamores along the canyon bottom, but still the rock formations formed of compressed ash from a long-extinct volcano were quite spectacular! Rock formations at left, and that is Laurie at right...
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Canyon parking lot - the plan was to mount the 500mm Canon camera lens to do some astrophotography for part of the night. Once set up, we both adjourned to Massai Point a half mile south for another project. I've always had a "thing" for the rock formation 5 miles to the north - the perfect profile of the Indian chief Cochise. While I've shot it many times before during the day, I was hoping to use the 4-day old moon's illumination to make it stand out a bit in the dark. At left is a shot right about sunset. Then after aligning the mount to Polaris and taking some sky flats, I returned to shoot Cochise with stars wheeling overhead. I found out that the moon was way too dim to even assist with locating the rock formation in the dark! I persevered and managed to take a passable frame.
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The next object was a "bright" comet, almost directly overhead. If it wasn't so close to Beta Andromeda (itself a guidepost to finding the Andromeda Galaxy) it might be harder to find. But being just north of Beta, I just put the bright star in the lower edge of the field and shot away - there it was, glowing green! This comet is 64P Swift-Gehrels, making a close appearance to the earth - only 43 million miles from the earth, and 130 million miles from the sun (the earth is about 93 million miles from the sun). The green glow is caused by solar radiation dissociating carbon molecules from the comet's nucleus, which glows green in the vacuum of space... The sharp-eyed among you might note a fuzzy spot just upper left from Beta Andromeda at the lower edge. That is NGC 404, long a test object to see if your telescope reveals it so close to a bright star. This is 10.5 minutes of stacked exposures.
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With the early sunset, we got in all the above observing, packed up and hit the road for the Tucson return about 10:30, hitting home about 12:30 - a productive night for the limited time on-sky!
Addendum!
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the wide-field shot of comet 65P Swift-Gehrels that also included the Andromeda Galaxy. Shown at left is a stack of 6 frames of 4 minutes total exposure taken with her T3i APS sensor camera with my 200mm lens. Please ignore the magenta halos around stars - they can sometimes be removed by adjusting focus slightly, but harder to remove in post-processing!
And at left is a labeled version - north is approximately at upper left... Note how obviously the greenish tint of the comet makes it so apparent! Unfortunately, it doesn't work when finding it visually as our eyes aren't sensitive enough to see colors on faint objects!
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