Way back in September, NASA'sJet Propulsion Laboratory sent a duo of Lockheed Martin-produced spacecraft toward one of its favorite test subjects, the Moon, as a part of its GRAIL mission -- Gravity Recovery And Interior Laboratory. Now, nearly four months later, the administration has announced that the GRAIL-A and -B twin crafts have planted themselves within our Moon's orbit. According to NASA, they're currently in "a near-polar, elliptical orbit with an orbital period of approximately 11.5 hours," and it plans to execute more "burn maneuvers" in the coming weeks to shorten that time frame to less than two. By March, the research crafts will be positioned in a "near-polar, near-circular orbit" 34 miles above its surface, at which point they'll begin surveying its gravitational pull, by using radio signals to determine the distance between both units.
With this information, NASA hopes to better understand how gravity works, both above and below the Moon's surface, by detailing the findings in a high-resolution map. NASA also says that scientists can utilize it to get further insight into how our planets formed. Notably, both spacecraft feature a MoonKAM (Moon Knowledge Acquired by Middle school students), that will allow students request pictures of specific areas the lunar surface for later study. Best of all, using NASA's "Eyes on the Solar System" web app, you'll be able to follow the paths of both spaceships in detail. You'll find full details about the GRAIL mission at the source links below.