New unmanned moon mission may unlock planet’s mysteries

Washington, Dec 17: NASA and MIT (Massachusetts Institute of Technology) have announced a mission to map the moon’s internal structure, gravity and reconstruct its thermal history, also helping to unlock secrets of evolution of the inner planets in our solar system.

Known as the Gravity Recovery And Interior Laboratory (GRAIL) mission, it will be led by MIT professor Maria Zuber and will be launched in 2011.

It will put two separate satellites into orbit around the moon to precisely map variations in the moon's gravitational pull. These changes will reveal differences in density of the moon's crust and mantle, and can be used to answer fundamental questions about the moon's internal structure and its history of collisions with asteroids.

GRAIL’s measurements of the gravitational field will come from very precise monitoring of changes in the distance between the two satellites. The resulting measurements will map the moon's gravitational field up to 1,000 times more accurately than any previous mapping.

The detailed information about lunar gravity will also significantly facilitate any future manned or unmanned missions to land on the moon. Such data will be used to program the descent to the surface to avoid a crash landing and will also help target desirable landing sites.

Moreover, the mission's novel technology could eventually be used to explore other interesting worlds such as Mars.

"After the three-month mission is completed, we will know the lunar gravitational field better than we know Earth's, " says Zuber, who is head of MIT's Department of Earth, Atmospheric and Planetary Sciences.

The new mission should also reveal details about lunar history, including the relative timing and effects of the myriads of huge impacts that created the craters and basins seen on the surface today.

The moon, with its airless, un-eroded surface, can help in the understanding the history of all the solar system's inner planets - Mercury, Venus, Earth and Mars. So, the mission should also help to unlock secrets of the evolution of all these planets.

"The moon has the best-preserved record of the solar system's early history, " said Zuber. “While on other planets, much of that record has been lost through erosion and other surface changes, ” she added.

“The technology used in this project can also be applied to future missions to map the gravitational fields of other interesting worlds such as Mars, where it could reveal the exchange of carbon dioxide between the polar caps and atmosphere or the movement of flowing subsurface water, ” said Zuber. "We could learn amazing things from such followup missions, ” she added.