On Dec. 17, 2012, NASAs GRAIL objective crashed into the moon. GRAIL represents Gravity Recovery And Interior Laboratory, and the objective included two twin spacecraft named Ebb and Flow that had to do with the size of a washer and clothes dryer. Artists principle of the two Gravity Recovery and Interior Laboratory (GRAIL) spacecraft orbiting the moon. NASA launched the twin probes in September 2011 to study the moons gravitational field in extraordinary detail. (Image credit: Lockheed Martin )They orbited the moon in tandem to map the moons gravity field. The objective lasted about 9 months, and they even finished a prolonged objective before the spacecraft began to run low on fuel, so NASA chose it was time to power them down. Both spacecraft bit the lunar dust quite strongly, falling faster than 3,700 miles per hour.Catch up on our entire “On This Day In Space” series on YouTube with this playlist. On This Day in Space Archive! Still insufficient space? Dont forget to have a look at our Space Image of the Day, and on the weekends our Best Space Photos and Top Space News Stories of the week. Email Hanneke Weitering at [email protected] or follow her @hannekescience. Follow us @Spacedotcom and on Facebook..
