Arecibo, Puerto Rico - April 23, 2020
The Arecibo Observatory is using its powerful radar system to track (52768) 1998 OR2, a near-Earth asteroid that will safely pass the Earth at a distance 16 times further than the distance to the Moon on April 29.
The radar data confirm that 1998 OR2 is approximately 2 km in diameter and rotates once every 4.1 hours, as was suggested by optical observations. The range-Doppler images uniquely revealed the overall shape of the asteroid and some smaller-scale topographic features, such as hills and ridges.
(Left) Mosaic of range-Doppler radar images of (52768) 1998 OR2 obtained on April 19-20 UT reveal the near-Earth asteroid to be approximately 2 km in diameter (7.5 m/pixel vertically) with a crater-like concavity rotating across the radar-illuminated side (top of image) during roughly 2 hours of radar imaging. (Right) Animation of delay-Doppler images from Apr 18 UT. Image credit: Arecibo Observatory/NASA/NSF.
The scientists and telescope operators at the observatory have been adhering to health and safety guidelines, limiting the number of observing scientists at the telescope and wearing masks during the observations in response to the COVID-19 pandemic.
Arecibo radar observations were collected April 13th and every day between April 16th through April 23rd. The team of observers includes Drs. Anne Virkki, Flaviane Venditti, and Sean Marshall from UCF/Arecibo Planetary Group, Dr. Patrick Taylor of the Lunar and Planetary Institute in Houston, TX, and the Arecibo telescope operators Israel Cabrera, Elliot Gonzalez, and Daniel Padilla.
In an international collaborative effort, the Svetloe Radio Astronomical Observatory near St. Petersburg, Russia, has also been receiving the AO radar waves that were bounced off of 1998 OR2 with their 32-meter radio telescope.
Click here for the press release about these observations!
The Arecibo Planetary Radar program is a project of the Near-Earth Object Observations Program in NASA’s Planetary Defense Coordination Office.