Saturday, August 18, 2012

LROC: Fresh crater in Komarov's fractured floor

A fresh crater splashing ejecta across the edge of a fracture in Komarov crater. Field of view is 2.5 kilometers, from LROC Narrow Angle Camera (NAC) observation M191967463R, LRO orbit 13324, May 18, 2012; native resolution 1.52 meters. View the 1650 x 1650 LROC Featured Image, HERE [NASA/GSFC/Arizona State University].
Sarah Braden
LROC News System

The wispy, bright rays of this small crater (~475 meters in diameter, 24.801°N, 151.687°E) extend down into the fracture (graben).

You can see that this small crater is younger than the fracture because the bright rays of the crater are not visibly deformed by the edges of the fracture.

Gradually, cratering events like this contribute to the erosion and infilling of fractures and other craters on the lunar surface.

Komarov crater is on the southeastern edge of Mare Moscoviense and is located at 24.59°N, 152.25°E (diameter 80.43 km). The floor was long ago filled with mare basalt, and then cut with a spectacular set of intersecting fractures, or graben. Graben form when a section of the crust sinks as two parallel faults pull the crust apart. Note that the northwestern section of Komarov's rim has an irregular shape. the irregular shape is likely due to a preexisting impact crater. The older crater influenced the formation of Komarov's rim, and may have been partially flooded with molten mare material when Komarov's floor was filled in.

LROC Wide Angle Camera context image of Komarov Crater; the red box marks the total area imaged in the LROC NAC frame containing the field of view in the LROC Featured  Image. View the original LROC context image HERE [NASA/GSFC/Arizona State University].

Explore the rest of Komarov's fractures in the full resolution LROC NAC frame, HERE.

Related Images:
Alphonsus crater mantled floor fracture
Gassendi's Fractures

Virtual view from an imaginary point 93 km over the lunar farside, south of Komarov. The LROC 302 ppd WAC mosaic draped over LOLA 128 laser ppd topography shows how pyroclastic flow overran the mare-filled Moscoviense floor. Both the famous long floor and Komarov are each well inside the larger, circular and less obvious Moscoviense basin [NASA/GSFC/LMMP/Arizona State University].

1 comment:

John Moore said...

Did a 3D (anaglyph format – red/cyan glasses etc.,) flyover of Koromov about a year back, but took it down as the final product was somewhat jerky. I’ll put it up again as parts in the video gives the viewer a 3D idea of the grabens that Sarah mentions.

The ‘bulbous nature of the crater’s central region is obvious, as, too, the irregular (pre-existing crater?). Sarah’s bright crater is just about seen at the end (0.41s), but note it’s not the bright one in the foreground.

Here’s the link (YouTube)