The second of two repurposed NASA probes reached lunar orbit July 17, the agency said, setting the stage for up to a decade of lunar observation.

The two craft, the first of which reached lunar orbit June 27, will study the internal composition of the Moon for the next seven to 10 years, NASA said in a July 19 press release.

The spacecraft have been dubbed Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s Interaction with the Sun, or ARTEMIS. They were formerly part of a cluster of five spacecraft called Time History of Events and Macroscale Interactions during Substorms, or THEMIS. Three THEMIS craft will continue their original mission: studying the magnetic environment around the Earth, its auroras and how these are affected by the sun.

Meanwhile, “from their new orbits about the Moon, ARTEMIS will collect important data about the Moon’s core, its surface composition, and whether it contains pockets of magnetism,” said Dave Sibeck, ARTEMIS and THEMIS project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md.

The ARTEMIS and THEMIS spacecraft were built by ATK Spacecraft Systems and Services of Beltsville, Md. The project is managed out of Goddard. The University of California, Berkeley, operated the THEMIS mission out of its Space Sciences Laboratory.

The THEMIS probes’ observations could help scientists work out ways to protect people and satellites in low Earth orbit from the harmful effects of particular radiation, NASA said in its press release.



NASA’s THEMIS Satellites Given New Moon Mission