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CAPE CANAVERAL, Fla. -- At Space Launch Complex 17B on Cape Canaveral Air Force Station, the start of the rollback of the mobile service tower from the United Launch Alliance Delta II rocket that will launch NASA's Gravity Recovery and Interior Laboratory mission is moments away. GRAIL will fly twin spacecraft in tandem around the moon to precisely measure and map variations in the moon's gravitational field. The mission will provide the most accurate global gravity field to date for any planet, including Earth. This detailed information will reveal differences in the density of the moon's …
