Difference between revisions of "December 19, 2011"
(Created page with "__NOTOC__ =Single Crater Septum= <!-- ws:start:WikiTextHeadingRule:0:<h1> --> <!-- ws:start:WikiTextLocalImageRule:6:<img src="/file/view/LPOD-Dec19-11.jpg/2...") |
|||
| Line 2: | Line 2: | ||
=Single Crater Septum= | =Single Crater Septum= | ||
| − | + | <!-- ws:start:WikiTextHeadingRule:0:<h1> --> | |
| − | + | <!-- ws:start:WikiTextLocalImageRule:6:<img src="/file/view/LPOD-Dec19-11.jpg/287252184/LPOD-Dec19-11.jpg" alt="" title="" /> -->[[File:LPOD-Dec19-11.jpg|LPOD-Dec19-11.jpg]]<!-- ws:end:WikiTextLocalImageRule:6 --><br /> | |
<em>left: image from LRO WAC mosaic, and right: close-up of Kies A from LRO WAC [http://target.lroc.asu.edu/da/qmap.html Act-REACT Quick Map]</em><br /> | <em>left: image from LRO WAC mosaic, and right: close-up of Kies A from LRO WAC [http://target.lroc.asu.edu/da/qmap.html Act-REACT Quick Map]</em><br /> | ||
<br /> | <br /> | ||
| Line 23: | Line 23: | ||
<br /> | <br /> | ||
<hr /> | <hr /> | ||
| − | |||
| − | |||
| − | |||
| − | |||
Revision as of 00:24, 3 January 2015
Single Crater Septum
left: image from LRO WAC mosaic, and right: close-up of Kies A from LRO WAC Act-REACT Quick Map
While looking at the wonderful nomenclature map Maurice Collins constructed with the LRO WAC mosaic I noticed a strange curved ridge
tangent to Kies A. It immediately reminded me of a similar curved ridge or septum between Plato K and KA. This latter case is explained
as being created by converging ejecta from two simultaneously formed craters, but Kies A is just a single crater, although its shape is non-
round. So I found a higher Sun LROC WAC view from the Quick Map - thanks ASU/NASA for two different mosaics! - that doesn't suggest
two almost completely overlapping simulataneous craters. There is a small scallop on the northeast side where a collapse removed a small
bite from the rim. Then I remembered a second case of a similar single crater arc at Cauchy. Cauchy is a perfectly normal circular crater so
the curved ridge does not require an unusual crater to form. I wonder if an oblique impact could produce such a curved septum? Neither
Cauchy nor Kies A is young enough to preserve rays to provide evidence for non-vertical impacts. Danny Caes had actually mentioned both
Kies A and Cauchy in an LPOD comment in 2009 and he wondered if there were more of them, which is still a good question. Finding more
examples might lead to clues as to their origin.
Chuck Wood
Related Links
Rükl plate 53
