August 19, 2014

Two Gaping Holes

image by Robert Reeves, San Antonio, Texas

I don't often get lost on the Moon, but I did with this photo. As you can guess, I am a fan of the big dramatic gaping holes along the terminator. I tripped over this scene Saturday morning while cruising for targets of opportunity at 7000mm focal length with my Skyris 274M camera. I am not sure what visual magnification that equates to, but it must be nearly 1000. At the time I didn't recognize the crater configuration due to the deep shadows. After processing it, it took me a while to realize the two big craters are Fracastorius at right and Piccolomini to the left. (North is to the right). I'll bet you can't say Piccolomini real fast five times and not have you day brightened! Fracastorius is a lava flooded horseshoe, bay-like crater on the southern shore of Mare Nectaris. Its central peak has been buried by mare lava flows. The crater is so wide that the natural curvature of the Moon is protruding the center of its floor up into the rays of the setting Sun that spill over the crater's rim. At the left, the tip of Piccolomini's central peak also just catches the setting sun.

Robert Reeves

Technical Details
Aug 16, 2014. Celestron 11 Edge HD, 2.5X Powermate, and Skyris 274M camera. Best 300 of 2000 frames stacked in Autostakkert2, wavelets in Registax 6, shake reduction filter and camera raw filter in Photoshop CC with attention to reducing noise in the deep shadows.

Related Links
21st Century Atlas chart 6.

---