Near-Earth object Near-Earth object A near-Earth object (NEO) is any small Solar System body whose orbit brings it to proximity with Earth. By convention, a Solar System body is a NEO if its closest approach to the Sun (perihelion) is less than 1.3 astronomical units (AU). If a NEO's orbit crosses the Earth's and the object is larger than across, it is considered a potentially hazardous object (PHO). Most known PHOs and NEOs are asteroids, but a small fraction are comets. There are over 19,000 known near-Earth asteroids (NEAs), over a hundred short-period near-Earth comets (NECs), and a number of solar-orbiting spacecraft
Near-Earth Object Camera Near-Earth Object Camera The Near-Earth Object Camera (NEOCam) is a proposed space-based infrared telescope designed to survey the Solar System for potentially hazardous asteroids. NEOCam would survey from the Sun–Earth Lagrange point, allowing it to look close to the Sun and see objects inside Earth's orbit. NEOCam would be a successor to the WISE mission; the principal investigator is also WISE's principal investigator, Amy Mainzer of NASA Jet Propulsion Laboratory. Proposals for NEOCam were submitted in 2006, 2010, and 2015 to the NASA Discovery Program, but it has not been selected for launch. The primary scientific goal of NEOCam is