October 24, 2011
Tele And Wide Views
imageS by André van der Hoeven, Netherlands
André submitted some images to LPOD, each including a closeup and a broader context view. I like them. This pair emphasizes how different imaging is from visual observing. I can only barely glimpse the rille infestation of Gassendi and the linear rille to the west, but André captures them clearly. It makes me think that in the old days of a hundred or so years ago (and up to a few years ago) observers had a difficult time increasing understanding of the Moon because they were never completely sure of what was actually there. Now with images like this the reality is there waiting to be interpreted and put into a story. The synoptic view is the place to start. Gassendi sits on an inner ring of the Humorus Basin - the ridge at center left that used to be called the Percy Mountains. Two outer rings are hinted at by the isolated collection of hills to the left and then beyond that an eroded scarp. Gassendi was tilted toward the center of Humorum as it subsided due to the increasing load of mare lavas. The lavas covered the crater's ejecta and rose up fractures under the crater to raise the floor, creating the rilles by fracturing, and some of the magma leaked onto the lowest part of the floor. At some point the large crater, Gassendi A, smashed into Gassendi's north rim, dislodging a massive landslide of rim material onto the big crater's floor, perhaps covering some of the rilles.
Oct. 22, 2011. C11 with powermate (2,5x) and an ED110. All images are made with a DMK21-618 version.
Rükl plate 52
Yesterday's LPOD: Relictland
Tomorrow's LPOD: Big & Little