Jupiter's Trojan asteroids lead and follow the giant planet around the Sun occupying stable locations where Jupiter and the Sun's gravity balance each other. Humans have discovered only a tiny fraction of the million of them larger than one kilometer or about 3,300 feet in diameter that are suspected to exist. Upon NASA's selection of the Lucy mission, Dr. Harold Levison of the Southwest Research Institute in Boulder, Colorado commented “Because the Trojans are remnants of the primordial material that formed the outer planets, they hold vital clues to deciphering the history of the solar system. Lucy, like the human fossil for which it is named, will revolutionize the understanding of our origins.”