Two Unusual Craters
Jay Albert - 2013
Pictured below is an unusual pair of craters near the southwest limb of the Moon. Schickard is humongous at just over 140 miles long. The crater’s width appears slightly squished due to the normal foreshortening of objects near the edge of the Moon’s sphere. One of Schickard’s stranger features is its broad strip of light material between the darker lava plains on either side of the crater’s floor. The crater was named for the early 17th Century German astronomer who was the first to attempt to determine a meteor’s path through our atmosphere by simultaneous observations from different places.
The crater Wargentin lies to the south of Schickard. While not as large as Schickard, it’s no shrimp at 54 miles in diameter (about the size of the better known crater Tycho). Wargentin was named for the 18th Century director of the Stockholm Observatory. What makes the Wargentin crater so unusual is not its size, but that it is filled to the rim with dark lava that had actually flowed over its northwest wall and covered the plain below. The crater’s elevated floor also has an interesting “Y” shaped pattern of low wrinkle ridges on its surface.
The image below of the Schickard and Wargentin craters was taken on August 18, 2013 at 11:24pm EDT with my Celestron 11” SCT and Celestron Neximage 5 Solar System Camera. This is a stack of the 5 best images out of a 10 second video of 199 frames. The video was first aligned, stacked and processed in Registax 6, then finished in Photoshop Elements 9. Schickard’s large white patch on the floor and the raised level of Wargentin’s floor over that crater’s northwest wall and the shadow on the smooth plain beyond are easily seen.Jay Albert