Continuous Refinement

Precovery on Risk List Asteroids

The service developed constitutes a robust system that consistently executes asteroid precovery searches, scouring an extensive indexed database of point source catalogs. Utilizing the ADAM platform, this pipeline conducts daily checks against the most recent asteroid risk lists from NASA's Jet Propulsion Laboratory (JPL) and the European Space Agency (ESA).

This system is capable of finding singleton observations in archival data, which can be submitted to the Minor Planet Center. Through this continuous process of orbital refinement using precovery, the service contributes significantly to our understanding and tracking of potentially hazardous asteroids, enhancing our preparedness for potential asteroid encounters.

Precovery on Risk List Asteroids


Orbits Refined


New Observations


Objects Derisked


Total # Risk List Objects

Updated September 20, 2023 at 03:31 AM

Recent Notable Precoveries

2019 TU

The orbital uncertainty is reduced the most when the observations are ‘outside the arc’, meaning the number of days the observations span is extended. In this case, all prior observations were found between 10/3 and 10/8. Our precovery search found a single observation on 10/1, extending the arc by 2 days. Single observations are often left out by other searches.

2015 GB1

2015 GB1 was completely removed from both the JPL and ESA risk lists after submitting these new observations. There has not been another opportunity to observe this object since its close approach in 2015 (and there likely will not be again until LSST is online).

Service Diagram