Friday, January 19, 2018

A Fine Winter Night!

Those of you who know me knows it doesn't take much to get me under a dark sky, so when buddy Laurie Larson expressed interest in coming down for a visit and a camera session under the stars, my answer was, of course, YES! So last weekend we headed west towards one of my favorite pieces of sky, that over Kitt Peak National Observatory. It was a job on that mountaintop that got me to Tucson, and after a stint as a full-time employee there in the '80s, another as a docent in the '90s, and another with their nightly observing programs in the '10s, it is still a favorite place to go, though one can't interfere with the night time activities there. I use one of the pull offs on the west side of the mountain for a sky that can't be beat! We made it to the Observatory well before they closed to the public and wandered around for a bit, finding I no longer know anyone working in the visitor center! The photo at left shows a view of the 4-meter telescope atop Kitt Peak from the road far below through a 500mm lens and a 6-frame mosaic assembled in Photoshop...

A bit later, after we finished atop the mountain, we went to the first pullout below the 4-meter telescope and set up my TEC 140 to do some real telephoto-lens imaging! With a focal length of 1,000mm, it works great if the seeing allows. Case in point is the shot at upper right. At right foreground is the San Xavier Mission, likely just under 40 miles distant. Above that is the Tucson International Airport, above that the Pima Air Museum and at top is the "Boneyard" of spare airplane parts at the Davis-Monthan Air Force Base!

Also, a couple months ago I documented the LBT shooting off the ARGOS laser from Mount Graham 120 miles distant! While easy at night, I've never spotted it during the day. While I couldn't see it in the viewfinder, I shot blind and sure enough, is also easy with a little Photoshop adjustment of brightness and contrast...

We moved down a few miles to my favorite pullout and set up a small tracking mount for wide-angle lenses, and the big AP1200 mount here to mount the 500mm lens, as well as another piggyback 300mm without breaking much of sweat! That is Laurie doing her best Vanna White impersonation...

The first object of the night was an unusual comet - 2016 R2 PanSTARRS. It has been putting on a good show in larger telescopes and digital detectors, with an unusual blue color due to an overabundance of CO. Not quite as impressive through the smallish 500mm lens (compared to some telescopes), but the color still comes shining through! This is 15 minutes of total exposure through the 500mm. The 10 exposures were stacked on the comet nucleus, so the star images are trailed due to the comet's motion.

Laurie was interested in chasing down some of her favorite sky objects through the 500mm telephoto, and took these of the Rosette Nebula at left, and the Horsehead Nebula at right. In both images, the colors are real - the red is mostly from ionized Hydrogen gas, the most common element in the universe! Also in both images, the gas is condensing to form new stars. In the Rosette Nebula at left, you can see there is a loose cluster of stars that have used up and/or blown out the gas from the center of the nebula accounting for its hollow appearance. The Horsehead nebula is similarly composed of dust and gas also forming new star systems. the cream-colored nebula at upper left is actually a "reflection nebula", reflecting starlight from nearby stars, compared to the red glow caused by the gas' fluorescence! The "horsehead" part of the nebula is a dark cloud blocking the glow from the hydrogen cloud behind it. The Rosette is 10 minute total exposure, the Horsehead is 22 minutes!


I was content with some wider-angle fields, so went with the small tracking device after the comet photo above. At left is the Winter Milky Way rising over the southern slopes of Kitt Peak. While we thought it was clear, the photos make it obvious that it was not, with thin clouds being lit up by distant city lights. Over looking towards the west was a different kind of light! While parts of the Milky Way is visible in both images, the searchlight-looking beam reaching nearly the zenith at the Pleiades is the Zodiacal Light - meteoritic dust in the plane of the solar system reflecting sunlight to us. It is bright this time of year in the evening sky, even outshining much of the Milky Way! Both of these frames are with the 16mm Fisheye, and are each 70 seconds long.

As the night wound down, I did a 2-frame mosaic of Orion with a "normal" 50mm lens. The effect of doing the mosaic is retaining a little more resolution, though blog limitations remove most all of those advantages! Visible through most of the Orion shot (at left), are a plethora of red hydrogen clouds, including the above Rosette Nebula in the upper right corner, and the Horsehead under the left-most star of the belt of Orion...

I took another Fisheye shot to close out the night as the night's attendees also departed the mountain, illuminating the roadway with their headlights. Just above the southern horizon near the "blip" of Baboquivari is the bright star Canopus. I never saw this star growing up in the Midwest as it never clears the horizon there. The "light domes" of a couple towns are visible - I think the glow just to the left of Canopus is the border town of Sasabe about 30 miles to the south. And on the right hand edge of the horizon, the largish town of Caborca about 90 miles away illuminated the cloud deck.

Even given the clouds it was a great, mild night for January. They just don't come often enough for my taste!

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