Friday, August 26, 2011

Outside Giordano Bruno

Impact melt outside Giordano Bruno. LROC Narrow Angle Camera (NAC) observation M161646501R, LRO orbit 8956, June 2, 2011; illumination from the southwest, incidence angle 71° and resolution 55 centimeters per pixel. View the full-size LROC Featured Image HERE [NASA/GSFC/Arizona State University].

Sarah Braden
LROC News System

Giordano Bruno (35.9°N, 102.8°E) is a Copernican-age impact crater known for interesting impact melt features. The crater is named after the famous Italian philosopher Giordano Bruno who lived during the Renaissance.

Today's Featured Image shows an impact melt flow outside of the crater walls. This impact melt was thrown from Giordano Bruno and landed about 6 km away from the rim. Some of the material was hot enough that it continued to flow after being emplaced on the surface. The direction of flow is toward the top of the frame, away from the rim of Giordano Bruno. Although formed by a different process, impact melts flow in much the same way as lava flows, forming lobes and exhibiting channels and levees. Like lava flows, they cease to move when their source is depleted or the melt cools and freezes into solid rock.

Bright, relatively young Giordano Bruno impact melt, visible in LROC NAC frame M161646501R, in context of a crop from a 76 meter/pixel resolution, 604nm mosaic of four LROC Wide Angle Camera (WAC) observations swept up in orbits 3044-3047, February 23, 2011. See a wider field of view HERE [NASA/GSFC/Arizona State University].

Giordano Bruno is one of the youngest large craters (22 km diameter) on the Moon. How old is "youngest"? Most of the time, geologists classify the youngest craters into a group called Copernican-aged craters. However, if humans went back to the Moon they could sample some of the impact melt outside of Giordano Bruno, bring the sample back to Earth, and then use radiometric age dating to estimate the age of the rock. Impact melt rocks can be used to measure the age of an impact since the rock's "isotopic clock" is reset when it returns to a molten state.

One hundred meter per pixel LROC WAC context image of Giordano Bruno. The red box shows the extent of LROC NAC frame M161646501R. The impact melt outside of Giordano Bruno is in the lower end of the frame. See the full-size context image HERE [NASA/GSFC/Arizona State University].

Full width view of NAC frame M161646501R. The LROC Feature Image released August 25, 2011 focuses in on the lobe of flash-frozen impact melt from Giordano Bruno above left [NASA/GSFC/Arizona State University].

Explore the entire NAC frame for more impact melt flows outside of Giordano Bruno!

Related Images:
King crater ejecta deposits
LROC: Mare Undarum "Action Shot"
Fragmented Impact Melt
Impact Melt Flows on Giordano Bruno
Delicate Patterns in Giordano Bruno ejecta
Young Giordano Bruno

Giordano Bruno captured by the Planetary Camera onboard Japan's Kaguya (SELENE-1) lunar orbiter in 2007 [JAXA/SELENE].

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