NASA's Grail project maps the moon's gravity field

Update, December 14: Here's a link to the NY Times story about the crash of the two satellites into the dark side of the moon, projected for Monday.

Ebb and Flow, two satellites that have been orbiting the moon collecting data about the moon's gravity field, have sent back enough data for NASA to release this video of the gravity field map.

As NASA describes it, the map shows:

an abundance of features never before seen in detail, such as tectonic structures, volcanic landforms, basin rings, crater central peaks and numerous simple, bowl-shaped craters. Data also show the moon's gravity field is unlike that of any terrestrial planet in our solar system.

Why is this important? The moon's surface preserves the record of impacts from other bodies (overgrown or underwater or fractured on Earth). There will be more data and more reports, until the two satellites crash later this month. Read more here.

You can see a map of the earth's gravitational field (it's not round) here.