Twin Moon-Mapping Probes Begin Extended Mission

摘要

A pair of robotic spacecraft in orbit around the Moon began collecting data on lunar gravity again at the end of August as part of the probes' extended mission. NASA's twin Grail spacecraft (short for Gravity Recovery and Interior Laboratory) are studying the lunar gravitational field in unprecedented detail to help astronomers better understand how the Moon - and other rocky bodies in the solar system - formed and evolved.