Washington, Sep 11 : US space agency NASA Saturday launched a new lunar mission that will enable scientists to better understand the moon's gravitational field and the lunar interior from crust to core.

Near-identical Grail-A and Grail-B -- short for Gravity Recovery and Interior Laboratory -- blasted off at 9.08 a. m. (1308 GMT) aboard a Delta II heavy rocket from Cape Canaveral Air Force Station in Florida, Xinhua reported.

The two craft will journey to the moon for more than three months, and enter a lunar orbit one after the other around New Year's Day.

The mission is relatively short in duration - just 90 days once the two spacecraft reach the orbit.

This is the first mission devoted to studying the core of the moon (IANS)