NASA's DART spacecraft captured these images of Dimorphos, a small asteroid moonlet, just seconds before impact on September 26. The mission was designed to test the effectiveness of deflecting an asteroid by slamming a spacecraft into its surface at high speed. Astronomers will monitor Dimorphos to see how the 14,000-mph impact changed its orbit around a larger asteroid, Didymos. Dimorphos is about 525 feet (160 meters) long. The image at left, shot 11 seconds before impact, shows the entire body from a distance of roughly 42 miles (68 km). At right, DART's final full image, from seven miles (12 km), was taken just two seconds before impact, and covers an area roughly 100 feet (30 meters) across. [NASA/JHUAPL]