The first of two NASA spacecraft that will map the gravity field of the Moon entered into orbit around the Moon today.
The Grail-A probe arrived at its destination after a three-month journey and put itself into lunar orbit at 4:21 pm ET this afternoon, Space.com reported. A second probe, Grail-B, is scheduled to join its twin tomorrow afternoon.
According to Space.com:
The Grail team will use the twin probes' measurements to construct highly detailed maps of the moon's gravitational field. These maps are expected to reveal a great deal about lunar composition, allowing scientists to draw insights about how the moon formed and how it has changed over time, researchers said.
"Grail will improve our knowledge of the Moon's nearside gravity by over 100 times what was previously known, and by over 1,000 times what was known on the far side," lead scientist Maria Zuber told BBC News.
One of the mysteries that scientists hope the probes will help them solve is why the near side of the Moon, which is smooth, looks so different from the rugged, mountainous far side, the New York Times reported.
The first gravity-mapping mission will take 82 days, BBC News reported. In early June, the Moon will go into eclipse behind the Earth. If the probes can outlast the darkness on their battery power, scientists will likely send them even closer to the surface later in 2012 to conduct a second study, according to BBC News.
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