NASA weighs options for potential post-Arecibo planetary radar capability

With the decommissioning of the Arecibo radio telescope, NASA is continuing to explore alternatives for potential planetary radar technologies, like a collaboration with the United States Space Force.¬†For decades, NASA has been using the radio telescope, which has a 305-meter-diameter¬†at Puerto Rico’s Arecibo Observatory as a radar, especially for near-Earth asteroid studies. Although the radar is not used to track asteroids, their orbits can be refined and characterized.

But the NSF (National Science Foundation), which does own the observatory, declared on November 19 that the telescope would be decommissioned after engineering tests revealed that the telescope was facing the risk of failure. The possibility of an unregulated failure is too high to enable crews to fix the damage; two cables that facilitate an instrument base hanging over the dish broke, one in the month of August as well as the other November 6, engineering studies concluded. NSF reported earlier, December 1, that with no casualties confirmed, the instrument base collapsed overnight.

At a November 30 discussion of the Agency’s Planetary Science Advisory Committee, Lindley Johnson, who works as the director in charge of the Planetary Defense Coordination Office of NASA, said that that was a difficult chance to take. His office finances Arecibo’s planetary radar job. Arecibo’s closing, he said, would have a “small negative impact” on the planetary defense work of NASA. NASA agency does have another radar facility that can also detect near-Earth asteroids as well as other objects. The facility is at Goldstone Observatory, California.  Since the latest installation of a new Klystron, the Goldstone radar is back in service. Compared to Arecibo, the Goldstone radar has certain perks, including the potential to see even more of the sky as well as higher resolution. The more efficient radar of Arecibo has a larger range, enabling it to identify more distant objects.

Another downside for Goldstone is it is situated within small military airspace, requiring radar observation teamwork that can make it impossible for time-sensitive studies. That procedure has enhanced slightly, Johnson said. The closing of Arecibo, Johnson concluded, provides an opportunity to explore planetary radar systems’ viability. “It is just about time to look at the next generation of capabilities for planetary radar,” he added. Instead of one monolithic dish, like Arecibo, clusters of smaller dishes are likely to be used.

He added that old buildings are “high maintenance” and hard to maintain running. “Technology moved on 30 years ago,” he said when Arecibo first gained planetary radar capability. “New technologies need to be taken advantage of.” Every future planetary radar system is expected to be carried out in cooperation with other organizations. With a few exceptions, including the Hawaiian observatory of the Infrared Telescope Facility, NASA Agency does not run ground-based telescopes but instead relies on the space-based observatories.