Porosity of the moon's crust reveals bombardment history: The moon sustained twice as many impacts as can be seen on its surface, scientists find. - Science Daily

Researchers find that, early in its history, the moon was highly porous, which was likely a result of early, massive impacts that shattered much of the crust. They reached their conclusions with simulations and data from NASA's GRAIL mission.

Around 4.4 billion years ago, the early solar system resembled a game of space rock dodgeball, as massive asteroids and comets, and, later, smaller rocks and galactic debris pummeled the moon and oth… [+5934 chars]

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