A section of the Sutter's Mill meteorite, dubbed "Darth Vader," is studied at a lab at the University of California, Davis. The meteorite is made of carbonaceous chondrite, which contains materials that formed the planets of the solar system. UC Davis hide caption

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The GRAIL mission's gravity map of the moon. Very precise measurements between two lunar probes orbiting the moon allowed researchers to study the moon with great detail. NASA/JPL/Caltech hide caption

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This picture received from North Korea's official Korean Central News Agency on Wednesday shows an orbit image of the satellite Kwangmyongsong-3, being monitored on a large screen at a satellite control center in Cholsan county, North Pyongan province in North Korea. AFP/Getty Images hide caption

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Cmdr. Eugene Cernan tests the lunar vehicle on the surface of the moon during the Apollo 17 mission. NASA hide caption

itoggle caption NASA