Seeing Double

Lucy, a NASA mission to the outer solar system, discovered that its first target, the asteroid Dinkinesh, is really a binary system, with a smaller asteroid orbiting the larger one. Lucy flew past the system on November 1, and snapped this image from a distance of roughly 270 miles (430 km), roughly one minute before its closest approach. Its observations show that the larger body is roughly one-half mile (.79 km) in diameter, with its companion about 0.15 miles (.22 km) across. Lucy's primary mission is to study Trojan asteroids, which share Jupiter's orbit around the Sun. Dinkinesh is in the main asteroid belt, between the orbits of Mars and Jupiter, and was added to the target after Lucy launched. In addition to adding to the knowledge of the asteroid belt, the encounter gave scientists and engineers a chance to test the spacecraft's targeting system and instruments. [NASA/GSFC/SwRI/JHUAPL/NOAO]