The JPL Center for NEO Studies (CNEOS) computes high-precision orbits for Near-Earth Objects (NEOs) in support of NASA’s Planetary Defense Coordination Office. These orbit solutions are used to predict NEO close approaches to Earth, and produce comprehensive assessments of NEO impact probabilities over the next century. Continually updated calculations of orbital parameters, close approaches, impact risks, discovery statistics, and mission designs to possibly human-accessible asteroids are made available on this website and to user scripts through an Application Program Interface (API). CNEOS supports observers through the JPL Horizons high precision ephemeris computation capability.

CNEOS is the home of JPL’s Sentry impact monitoring system, which performs long-term analyses of possible future orbits of hazardous asteroids, searching for impact possibilities over the next century. Similarly, the CNEOS Scout system monitors the MPC webpages of new potential asteroid discoveries and computes the possible range of future motions even before these objects have been confirmed as discoveries.