NASA crashed two of its probes into the moon on Monday in order to find out what's underneath the lunar surface.
The twin Grail probes, known as Ebb and Flow, successfully smashed into a mountain on the moon surface at 5:28 p.m. ET Monday, ending their one-year mission.
"We have lost signal," a voice reported during a live video stream, as engineers and onlookers at NASA clapped. "We have passed the point of impact."
Maria Zuber, a professor of geophysics at MIT, told a reporter immediately following the successul impact that "NASA has approved the Grail team's request to name the final resting place of Ebb and Flow after our teammate, Sally Ride." Ride, a pioneering female astronaut, died earlier this year.
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Viewers were able to catch the action live on NASA's website, beginning at 5 p.m. EST, or on Space.com.
Viewers got a behind-the-scenes look at the mission, although anyone hoping for a glimpse of the actual crash was out of luck.
The impact site was in shadow at the time, so no video of Ebb and Flow's actual violent demise was available.
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Scientists carefully controlled the impact of the "washing machine-sized probes," monitoring them to "avoid the risk of obliterating Neil Armstrong's footsteps on the moon," SKY News reported.
The $496 million Grail mission — short for Gravity Recovery and Interior Laboratory — launched in September 2011, and Ebb and Flow have been zipping around the moon ever since, mapping its gravity field in unprecedented detail, according to Space.com.
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