August 14, 2022
Originally published September 22, 2012
image by Raffaele Barzacchi
The rilles in Gassendi are not equally prominent. The ones on the right in Raf's image are deeper, sharper-edged, wider and more linear than the rilles along the bottom and on the left. Only one rille at upper left seems as sharp. The rilles on the right cut material that is smooth textured and light hued. If it is volcanic it isn't the same iron-rich lavas as the dark maria. The terrain on the left is rubbly and a wide swath of hilly material arcs across the top and left, and a ring of hills is along the bottom right. Does the difference in terrain cause the differences in the rilles? For example, it is possible that the smooth terrain is stronger so that when a rille forms it is sharply defined because its edges don't crumble. Or the right side rilles might be sharper just because they are younger. What evidence do you see that might explain the differences?
Sept 3, 2010, 01:31 UT. C14XLT, f/20, R+IR filter, PRG CCD@20 fps, res 90%.
Rükl plate 52
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