April 21, 2009

Just a Piece

south up image by Yuri Goryachko, Mikhail Abgarian, Konstantin Morozov, Minsk, Belarus

This is just a piece of a huge new mosaic by the Minsk Miracle Imagers, but it is enough to reinvigorate the discussion of the origins of smooth plains
in the highlands. Just in from the terminator on the bottom right side of the image there is strong contrast between the small craters and hillocks that are
almost everywhere and the very smooth material on the floors of some craters. To discuss these ponds we need to agree on what is visible here - at the
top center, the large bright rim on the terminator is Moretus, and the eastern rim of Clavius is at center right. The smooth material on crater floors and
between craters is most visible to the left and bottom left of Clavius. The standard interpretation is that this material is ejecta from the formation of the
Orientale Basin. Seventy-cm radar images document that ejecta does travel this far, and in fact, made me think that that is what the smooth material
probably is. But the Minsk image reminds me of how localized and discontinuous the smooth plains are. I would think that the smooth-flowing ejecta should
be more widespread and continuous. But if the smooth stuff is some sort of volcanism there are no apparent vents anywhere. I don't see compelling evidence
for either interpretation.

Chuck Wood

Technical Details
April 3, 2009, 15:35 UT. 230 mm Mak-Cass, F=3000 + 2X barlow + Unibrain Fire-i 702 CCD camera (IEEE-1394, 1388x1040, 18 fps) + Astronim red filter. Processing in Registax, Avistack and Maxim DL.

Related Links
Rükl plate 73
Minsk Miracle Imagers website

Yesterday's LPOD: Why not Venus?

Tomorrow's LPOD: The Kiss of Fire

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