Rain of meteorites makes the moon hum

THE man in the moon is humming a tune, but thankfully the noise won't drown out sensors on future missions peeking at the lunar interior.

A steady barrage of small meteorite impacts should cause the moon to "ring", but no seismometers sent to the moon to date have been sensitive enough to hear it. So Philippe Lognonné at the Institute of Earth Physics of Paris and colleagues decided to work out how loud the ring is....