Arecibo Radar Observations

The Arecibo Observatory in Puerto Rico housed the world’s most sensitive and most powerful planetary radar system. Radar observations by Arecibo refined the orbits of over 850 near-Earth asteroids (NEAs) as well as characterized many of their shapes, sizes, spins, and surfaces. Arecibo planetary radar was invaluable in confirming the existence of NEAs with their own moons (i.e., binary and triple asteroid systems), verifying how sunlight slowly changes the orbits and spins of NEAs over time, and imaging a number of NASA spacecraft mission targets, including Bennu, explored by the OSIRIS-REx mission, and the Didymos binary system, target of the upcoming DART mission.

This data repository includes information on NEAs studied by Arecibo, along with radar echo-power spectra and a sample of radar images when available. In some cases, when sufficient imaging of an NEA is available, an animation of a sequence of radar images is also provided. To learn more about how Arecibo created these data products, check out the “How Radar Works” section!

The Arecibo Observatory in Puerto Rico is a facility of the National Science Foundation. The Arecibo Observatory planetary radar project is fully funded by NASA through the Planetary Defense Coordination Office by a grant from the Near-Earth Object Observations program.

This database is currently in its beta version. We are working to fully populate it with Arecibo planetary radar data. Downloadable formats of the posted data, rather than images, will be made available in the future. For access to raw data, please contact the planetary radar staff at Arecibo Observatory.

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