October 4, 2013
Raising the Bar
image by Damian Peach
About 18 months ago I added a new page to the Moon Wiki called The Best Ever! for LPOD images that are superb. I neglected that page for too long; we have another addition to that list today (and really many more to be added from the last few months). Damian's image captures an apparent string of bright and dark knots along the north wall of Posidonius that actually is one of the most sinuous rilles on the Moon. Previously we relied on a series of Apollo 15 images that revealed the true nature of this rille, and its continuation that hugs the crater's western rim, but now a single LRO mosaic shows nearly all of it (and a privately processed LRO is even more dramatic). On Earth, river meanders depend partially upon the slope of the ground traversed - steep is straight, and very flat meanders. Presumably this is also true on the Moon for sinuous rille lava flows. LRO altimetry data provide the opportunity to compare rille slope and sinuosity - an M.S. project waiting to be started. Finally, you might be a little embarassed to notice the dark fishhook - an apparent defect - on the wall of Posidonius J just northeast of the crater. Don't be, its a real lunar feature.
Sept 24, 2103. 356mm reflector. ASI120MM.
21st Century Atlas chart 8.
Damian's Facebook page
Yesterday's LPOD: Part of an Unseeable Universe
Tomorrow's LPOD: Peakly Pleasures