The twin Grail spacecraft are expected to launch from Florida's Cape Canaveral Air Force Station today (Sept. 10) at 8:29 a.m. EDT (1229 GMT), with a second opportunity available at 9:08 a.m. EDT (1308 GMT), if needed, NASA officials said. But beyond new lunar science, the Gravity Recovery and Interior Laboratory, GRAIL, will also help cement NASA's legacy of lunar exploration in the public imagination. [Video: Grail's Mission to Map Moon Gravity] 
 
 Infographic shows how GRAIL mission maps the moon's gravity field Credit: Karl Tate, SPACE.com 
 
 The twin Grail spacecraft, called Grail-A and Grail-B, will closely examine the composition of the lunar interior, and will make detailed and precise maps of the moon's gravitational field.
– NASA's not done with the moon yet. It launched two unmanned spacecraft today (Grail A and Grail B) to study the lunar gravitational field and interior, reports Space.com. The $496 million mission has an interesting twist, notes the PopSci blog: a MoonKAM that will allow students to log in, scan the moon's surface, and request particular images for study. The two probes, which lifted off aboard a Delta 2 rocket shortly after 9am EDT, aren't expected to be in place until the end of the year. (If you like your moon missions with astronauts, click here for newly released images of the Apollo era.)