The twin GRAILl lunar probes are slated to blast off from Florida's Cape Canaveral Air Force Station on Thursday. The mission has two instantaneous (one-second) launch windows on that date, one at 8:37 a.m. EDT and another at 9:16 a.m. EDT (1237 and 1316 GMT), NASA officials said.
The two unmanned spacecraft should reach the moon around New Year's Day, at which point they'll begin probing the moon's composition from crust to core. GRAIL's observations should help scientists better understand how the moon formed and evolved, researchers said.
NASA to launch twin moon probes
