NASA - National Aeronautics and Space Administration

Spacecraft: GRAIL
Launch Vehicle: United Launch Alliance Delta II Heavy
Launch Site: Cape Canaveral Air Force Station
Launch Pad: Space Launch Complex 17B
Launch Date: Sept. 10, 2011
Launch Time: 9:08:52 a.m. EDT



Image at right: At Cape Canaveral Air Force Station's Space Launch Complex 17B, a United Launch Alliance Delta II heavy rocket lifts off carrying NASA's GRAIL spacecraft on its lunar mapping mission. Image credit: Thom Baur, United Launch Alliance
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Twin GRAIL Spacecraft Begin Journey to the Moon Aboard Delta II Rocket

A United Launch Alliance Delta II rocket successfully sent NASA's twin moon-bound GRAIL spacecraft on their way at 9:08 a.m. EDT on Sept. 10, 2011. The launch came during the second window of the day when upper-level winds proved out of limits during the day's first opportunity, just as they had during the first launch attempt on Sept. 8.

The twin spacecraft will study the moon in unprecedented detail. GRAIL-A is scheduled to reach the moon on New Year's Eve 2011, while GRAIL-B will arrive New Year's Day 2012. The two solar-powered spacecraft will fly in tandem orbits around the moon to measure its gravity field. GRAIL will answer longstanding questions about the moon and give scientists a better understanding of how Earth and other rocky planets in the solar system formed.

› GRAIL/Delta II Summary (PDF 650KB)

GRAIL Webcast