(CNN) - NASA delayed its Thursday launch of a moon research mission because of weather issues and will retry on Friday.
The mission, called GRAIL, will study how the moon was formed. It will explore "the structure of the lunar interior, from crust to core... to advance understanding of the thermal evolution of the moon," NASA said.
Two lunar orbiters are aboard a United Launch Alliance Delta II rocket, which will launch from Cape Canaveral, Florida. NASA will retry the launch at 8:33 or 9:12 a.m. ET Friday.
The crafts - GRAIL-A and GRAIL-B - will eventually separate from the Delta rocket. GRAIL stands for Gravity Recovery and Interior Laboratory.
Once in orbit, the orbiters' speeds will increase when they pass over formations on the moon's surface, allowing scientists to measure those formations based on the distance between the two spacecraft.
GRAIL is also partnering with Sally Ride Science to set up "MoonKAM," an educational program. Teachers will be able to register their classes and allow their students to explore specific regions of the moon in detail through pictures taken by the spacecraft.