(PhysOrg.com) -- NASA has invited 150 followers of the agency's Twitter accounts to a two-day launch Tweetup Sept. 7-8. The Tweetup is expected to culminate in the launch of the twin moon-bound GRAIL spacecraft aboard a Delta II rocket from Cape Canaveral Air Force Station in Florida.
The launch is targeted for 5:37 a.m. PDT (8:37 a.m. EDT) on Sept. 8. The two GRAIL spacecraft will fly in tandem orbits around the moon for several months to measure its gravity field in unprecedented detail from crust to core. The mission also will answer longstanding questions about the moon and provide scientists with a better understanding of how Earth and other rocky planets in the solar system formed.
Tweetup participants were selected from more than 800 people who registered online. They will share their Tweetup experiences with their followers through the social networking site Twitter.
Participants represent the United States, Australia, Brazil, Canada, India, Indonesia, Spain and the United Kingdom. Attendees from the U.S. come from 32 states: Alabama, Arizona, California, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Illinois, Indiana, Kentucky, Louisiana, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, New Hampshire, New York, North Carolina, Ohio, Oregon, Pennsylvania, South Carolina, Tennessee, Texas, Utah, Virginia, Washington and Wisconsin.
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