Images of a possible new Lunar sunrise ray

On the evening of October 5, 2000, I set up my 8" f/6.8 Dobsonian telescope and my jackleg webcam video setup (Alaris QuickVideo weeCam USB, Gateway Solo 2500 laptop w/ 64 MB RAM, 300 MHz).  I was planning to try to photograph "my" ray, originally reported in April 1999, in Longmontanus, but it turned out I was in excess of 24 hours early; Longmontanus and even Clavius were still in full darkness (you can see Clavius in the image below as the large dark indent in the terminator WSW from Heraclitus).  Still, I had my telescope out and cooled, so I slid in a 25 mm eyepiece and 2x Barlow for 108x and patrolled the terminator to see what might be worth shooting some images.

As I scanned, I noted a crater very far south that showed a narrow ray.  After running inside for my Rukl atlas and doing a little crater hopping from the very distinctive Heraclitus complex, I identified the crater as Curtius. Since I didn't recall ever seeing  any reference to a ray in Curtius, I finished the setup to take images, and shot several 640x480 images and a few AVI video clips of that region.

Here you see an image (north at top) cropped from the best of the 640x480 images -- this was originally shot at f/13.6 including a 2x Barlow, then converted to grays, auto contrast enhanced, sharpened and brightened in ImageForge.  Near the top you can see the Heraclitus complex, and in the oval is Curtius.  The limitations of my webcam setup prevent seeing as much of the ray as was visible with an eyepiece; at 108x I was able to see more light extending toward the east crater wall, where a smaller crater interrupts the wall and allows the rising sun to shine through the gap onto the crater floor, creating the ray.

Curtius Sunrise Ray
Image Copyright © 2000 by Donald Qualls

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