New Mission Artemis Studying The Moon

Two small NASA probes that had been used to study space weather now are ORBITING THE MOON to study its interior and surface composition. The spacecraft, called Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS), began their journey away from Earth's orbit in July 2009. The first spacecraft entered lunar orbit on June 27, and the second on July 17, 2011.

The probes will now approach the moon's surface to within sixty miles once per orbit. The data will provide scientists with new information about the moon's internal structure for the next seven to 10 years.

Both spacecraft were previously in areas called the Lagrangian points, areas on either side of the moon, where the moon and Earth's gravity balance perfectly. These locations were ideal spots to study Earth's distant magnetic field and how the solar wind, made up of ionized gas known as plasma, flows past the moon and tries to fill in the vacuum on the other side.

The ARTEMIS mission was made possible by repurposing two spacecraft that would otherwise have ceased operations in 2010. The spacecraft were part of NASA's Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission launched in 2007.

Source: space-wanderers.blogspot.com