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Center for NEO Studies (CNEOS)

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.

In the event of a predicted impact such as for 2008 TC3, CNEOS predicts the impact time, location and geometry. Hypothetical impact scenarios are developed for use at the Planetary Defense Conferences and similar exercises at other meetings. In collaboration with the Aerospace Corp., CNEOS provides the NEO Deflection App, which computes how far a hypothetical asteroid would move if deflected by a known amount at an earlier time.

CNEOS provides a data page for every NEO, giving its orbital parameters, a close approach summary, an interactive orbit viewer and other ancillary data such as discovery circumstances. Parameters are archived in the JPL Small-Body DataBase (SBDB), which can be searched using a highly configurable filtering tool.