Near-Earth object NEOs pass Earth closer than the distance of the Moon. On August 10, 1972, a meteor that became known as the 1972 Great Daylight Fireball was witnessed by many people; it moved north over the Rocky Mountains from the U.S. Southwest to Canada. It was an Earth-grazing meteoroid that passed within of the Earth's surface, and was filmed by a tourist at the Grand Teton National Park in Wyoming with an 8-millimeter color movie camera. On October 13, 1990, Earth-grazing meteoroid EN131090 was observed above Czechoslovakia and Poland, moving at along a trajectory from south to north. The closest approach
Near-Earth Asteroid Scout mission researchers argue that "characterization of NEAs that are larger than 20 m in diameter is also of great relevance to inform mitigation strategies for planetary defense." The planned target, subject to change, is near-Earth object 1991 VG. 1991 VG was discovered shortly before passing just 0.003 AU from earth on 6 November 1991, and returned within 0.06 AU of Earth in August 2017. It raised interest due to the close approach, and the expectation that such an Earth-similar orbit would not have long term orbital stability. Once the flyby is complete, and if the system is still fully functioning,