LRO Sees Bouncing, Rolling Boulders on the Moon

[jakeXT]

Think nothing ever happens on the Moon? New images from the Lunar Reconnaissance Orbiter Camera shows spectacular views of the famous Tsiolkovskiy Crater, and a close-up look reveals boulders that have rolled down the slopes of the crater. In the larger image, below, it is easy to see where the boulders came from by following their rolling, bouncing tracks. These are not small rocks by any means: the largest boulder in this image is about 40 meters wide – half as big as a soccer field! Seeing where the boulders originated from is a great clue to geologists reconstructing the local geology. What do they see here?

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http://www.universetoday.com/2009/09/02/lro-sees-bouncing-rolling-boulders-on-the-moon/

[1620rock]

1. Fascinating. Thanks for posting!!!

[Warpy]

2. Moonquakes?

There's plenty of reason to think they exist.

They're not being blown down or washed down, after all.

[Posteritatis]

3. Or an impact or something

Given how static the lunar surface is, there's no real reason to believe those boulders and those tracks haven't been there longer than humans have existed.

[Ian David]

4. Could be caused by the same forces that bring rocks to the surface on Earth.

Repeated heating and cooling, contracting and expanding.

(Rocks deep in the earth are raised by tectonic forces. Rocks in topsoil are raised to the surface by repeated heating and cooling.)

Except in this case, instead of forcing rocks up from the surface of soil, it's shifting the balance of precariously situated boulders. Especially, perhaps, if the heating and cooling is uneven (like if half of a rock is in shade during the lunar day).

[formercia]

5. Gravity at work. n/t

[roguevalley]

6. wow.