Impact Melt Fingers

Impact melt from an unnamed lunar crater forms ghostly fingers stretching across the Moon's surface. LROC NAC frame M126091916L, image width is 560 m [NASA/GSFC/Arizona State University].

When impact melt is ejected from a crater the melt forms flows or ponds. In today's Featured Image we see an example of multiple flows spreading out from what was initially the same impact melt deposit. The "fingers" of impact melt are flowing radially away from the rim of the parent crater. What caused the impact melt to split into separate flows? Was it the velocity and direction of the initial impact of the melt, the shape of the existing topography, or another change that occurred moments after the parent crater's formation?

This impact melt deposit originates from a young, unnamed lunar crater (located at 66.63°S, 128.61°E, ~13 km in diameter) inside another larger crater called Grotrian (located at 66.17°S, 128.23°E, 36.78 km in diameter). Both craters are north of the Schrödinger basin (79.30°S, 126.50°E). In the LROC WAC context image below you may also notice a long valley oriented north-south starting from north of crater Grotrian. This is Vallis Planck (451 km long), which was probably formed as a result of ejecta from the Schrödinger basin impact.

LROC WAC context image of the crater Grotrian and the surrounding geology. The white asterisk to the west of the unnamed crater marks the location of the Featured Image [NASA/GSFC/Arizona State University].

More interesting impact melt features are located around the western rim of this unnamed crater. Explore the entire NAC frame!

Related posts:

Herigonius K Impact Melt Flow

Rootless impact melt flows

Forked Impact Melt Flows at Farside Crater

Published by Sarah Braden on 8 May 2012