image by Mike Wirths
When a magnificent image comes in to LPOD there are usually many well defined features to discuss. For example, Mike’s new image of the Lambert to images, but this may be the first time it has been imaged from Earth. This Pytheas I rille (I just named it) is a slightly sinuous rille starting in the south and winding northward until it hits the tip of a mare ridge. The Metric Camera view shows that the rille cuts through the ridge and continues northward another 20-30 km; the northward extension is also visible on Mike’s image. This faint rille and similar ones that show up where ever there are very high resolution mare images with low lighting illustrate how mare lavas were emplaced. Lava erupts onto the surface and flows rapidly downhill, zigging and zagging around small topographic obstacles. Levees form along the margins of the flow, constraining it within a channel that we call a rille. Probably rilles occurred widely across the mare but have been eroded by the steady rain of small random impacts, or in this area by the splat of secondary clusters.
17 August 2006. 18″ Starmaster + camera Lumenera Infinity 2-2 + 2.5X Powermate barlow + red filter; Registax 3 MAP processing (18 points). CAW stretched this beyond the tonal smoothness of Mike’s original to better show the rille.
Rükl charts 20
Lunar Orbiter IV view
Yesterday's LPOD: Better Than Orbiter
Tomorrow's LPOD: A Single Twin