Posted: Sat, Sep 10, 2011, 12:56 PM ET (1656 GMT)
A Delta 2 rocket successfully launched a pair of NASA spacecraft that will study the Moon's interior. The Delta 2 7920H lifted off from Launch Complex 17B at Cape Canaveral Air Force Station, Florida, at 9:08 am EDT (1308 GMT) during the second of two one-second launch windows available Saturday. The rocket's upper stage deployed the twin Gravity Recovery and Interior Laboratory (GRAIL) spacecraft a little over an hour after liftoff. The two spacecraft will enter orbit around the Moon in four months, where they will map the Moon's gravity field to far higher precision than before, yielding new information about the Moon's interior. A launch attempt Thursday was scrubbed by high-level winds, while technical issues postponed Friday's launch attempt. The launch is the last scheduled Delta 2 launch from Cape Canaveral; one more Delta 2 is slated for launch next month from Vandenberg Air Force Base in California.
