Grail Spacecraft

Two Gravity Probes Science Mission is Ready to Get Under Way

NASA two gravity probes are successfully in orbit around the moon, and their science mission is ready to get under way. NASA’s twin Grail spacecraft arrived at the moon over the New Year’s weekend, seamlessly slipping into lunar orbit after more than three months of journeying through space. The probes are designed to map the moon’s gravity in unprecedented detail. By shedding light on the lunar gravity field, researchers hope to better understand how the moon formed and evolved. Currently, both spacecraft are operating independently, but after a series of engine maneuvers, the two probes will be placed in a tandem orbit just 34 miles (55 kilometers) above the moon’s surface. Then, the Grail probes will be ready to begin collecting data in early March, accordinhg to Maria Zuber, Grail principal investigator at the Massachusetts Institute of Technology in Cambridge, Mass..One spacecraft will fly in front, and the other behind, in a polar orbit as the moon slowly rotates beneath them. In that way, scientists will map the moon, determine the gravity field, and gain understanding of the inside of the moon.