Cookie consent

AstroBin saves small pieces of text information (cookies) on your device in order to deliver better content and for statistical purposes. You can disable the usage of cookies by changing the settings of your browser. By browsing AstroBin without changing the browser settings, you grant us permission to store that information on your device.

I agree
Valle Schroteri and Aristarchus Crater, 


            Bruce Rohrlach

Valle Schroteri and Aristarchus Crater

Technical card

Resolution: 1574x1599

Date:Jan. 19, 2019

Focal length: 7000

Seeing: 4

Transparency: 7

Locations: Boronia, Melbourne, Victoria, Australia

Data source: Backyard


Cropped image of the eye-catching pair of lunar craters Aristarchus and Herodotus on the Aristarchus Plateau (a 200km wide tilted crustal block) which arises out of Oceanus Procellarum. Obtained quite good resolution of the terraces on the inner walls of the Aristarchus crater last night when Aristarchus was located near the terminator. The Aristarchus area is one of the highest lunar albedo regions, and particularly its central crater-floor peak. This bright region can be seen with the naked eye on a clear night, but is truly dazzling in a high aperture telescope. The inner parts of the outward projecting rays of Aristarchus are visible here but not well high-lighted. They are asymmetric and spread out on the east and southeast sides (left in image) indicating an impact coming in from the north/northwest direction (from the right) at a significantly inclined angle. Vallis Schroteri is a stunning feature (similar in scale to the Grand Canyon on earth) and is one of the longer lunar rilles, emanating from a 6-km-wide crater associated with the “Cobra Head” and meandering across the Aristarchus Plateau for 160 km.

The rille has a maximum 10km width and narrows to 1 kilometre wide near its terminus at a 1-km-high precipice on the edge of Oceanus Procellarum. It contains an inner valley-floor rille that has a total length of 204 km. This sinuous feature is of volcanic origin although the exact mechanics of formation is being debated: carved lava channel Vs collapsed mega-scale lava tube Vs some combination of lava tube and contemporaneous surface flow and side-wall channel caving. Regardless of the exact mechanism, a 160-km-long by up to 10-km-wide river of lava scorched down the Schroteri valley (rille) before pouring onto the mare of Oceanus Procellarum on the edge of the plateau. The Aristarchus and Herodotus impacts formed later, the youngest being the Aristarchus crater which is so young (~450 million years old) that the solar wind has not yet had time to darken the excavated material by “solar weathering” - hence the extremely high albedo nature of this region.

Imaged from home in Boronia, Melbourne 19 January 2019: Skywatcher 8 inch/f5 telescope, ASI1600mm Pro camera and 5X Televue powermate. System Focal Length ~7000mm.



Bruce Rohrlach
License: None (All rights reserved)


Valle Schroteri and Aristarchus Crater, 


            Bruce Rohrlach