Two NASA Probes Tackle New Mission: Studying the Moon
WASHINGTON -- A NASA led team of scientists and engineers has repositioned two small probes from Earth’s orbit where they studied space weather to begin orbiting the moon to study its interior and surface composition.
The probes, called Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s Interaction with the Sun (ARTEMIS), began their lunar orbit journey over a year and a half ago. The first spacecraft was successfully inserted into lunar orbit on June 27. The second was positioned July 17. Both spacecraft were previously in an area called the Lagrangian points, or points on either side of the moon where the moon and Earth's gravity balance perfectly. This location was an ideal spot to study magnetism 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 probes will now orbit the moon’s surface at approximately less than one hundred miles once per orbit. The data will provide scientists with new information about the moon’s internal structure for the next 7-10 years.
"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. “ARTEMIS will also provide information needed to understand the moon’s environment in space.”
Engineers used complex orbit maneuvers to relocate the spacecraft to their new locations. The journey required many gravity assists from the moon and Earth and used minimal amounts of fuel.
“This is a good example of how new research goals and existing space flight assets can be used to do additional science by innovative use of an existing spacecraft,” said Dick Fisher, director, Heliophysics division, Science Mission Directorate, NASA Headquarters.” The quality of the original design and construction the spacecraft creates a double win: a new research opportunity for the space science community with no additional cost to the nation’s taxpayers.”
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. The mission consisted of five identical spacecraft that studied magnetic environment around Earth, the aurora, and how these are affected by the sun. The other three THEMIS probes continue their original science mission. Substorms are atmospheric events visible in the Northern Hemisphere as a sudden brightening of the Northern Lights. The findings from the mission may help protect commercial satellites and humans in space from the adverse effects of particle radiation.
The ARTEMIS mission is a joint effort between Goddard, NASA's Jet Propulsion Laboratory in Pasadena, Calif., the Space Sciences Laboratory at Berkeley, and UCLA. Goddard manages the program for NASA’s Science Mission Directorate.
THEMIS was the fifth medium-class mission under NASA’s Explorer Program. The program, managed by the Explorers Program Office at Goddard, provides frequent flight opportunities for world-class space investigations in heliophysics and astrophysics. The University of California, Berkeley’s Space Sciences Laboratory in Berkeley, Ca., managed the project development and operated the THEMIS mission. ATK Space (formerly Swales Aerospace) of Beltsville, Md., built the THEMIS satellites.
For more about the ARTEMIS mission, visit:
Goddard Release No. 11-042
Goddard Space Flight Center, Greenbelt, Md.