NASA Sentry is an automated monitoring system developed by NASA's Center for Near-Earth Object Studies (CNEOS) to track and assess potential asteroid impact risks. The system continuously scans newly discovered near-Earth objects (NEOs) and calculates their future orbital paths to determine if they pose any threat to Earth.

Using advanced algorithms and observational data, Sentry predicts possible collisions over the next 100 years, assigning a probability score to each potential impact scenario. If a new object is found to have a non-zero impact probability, it is listed in the Sentry Risk Table, which is regularly updated as new data becomes available.

Sentry plays a crucial role in planetary defense, allowing scientists to anticipate and prepare for potential asteroid threats well in advance. In 2023, NASA introduced Sentry-II, an upgraded version with improved computational capabilities, capable of handling complex gravitational interactions more accurately.

By providing early warnings and precise impact probability calculations, NASA’s Sentry system helps ensure Earth’s safety from potential cosmic hazards.