Radar Data Yields High-Resolution Views of Near-Earth Asteroid HQ124

On June 8th, with a radio source beamed at the asteroid designated 2014 HQ124 (less formally, "the beast") while two other telescopes tracked that beam's reflections, NASA was able to gather high-quality images of the object as it zipped by a mere 776,000 miles from Earth. (Some asteroids are closer, and a vast number of them could soon be better known, but none have allowed as good an opportunity for radar obvservation.) Astronomy Magazine's account adds a bit more detail: To obtain the new views, researchers paired the 230-foot (70m) Deep Space Network antenna at Goldstone, California, with two other radio telescopes, one at a time. Using this technique, the Goldstone antenna beams a radar signal at an asteroid and the other antenna receives the reflections. The technique dramatically improves the amount of detail that can be seen in radar images. To image 2014 HQ124, the researchers first paired the large Goldstone antenna with the 1,000-foot (305m) Arecibo radio telescope in Puerto Rico. They later paired the large Goldstone dish with a smaller companion, a 112-foot (34m) antenna, located about 20 miles (32km) away. ... The first five images in the new sequence — the top row in the collage — represent the data collected by Arecibo and are 30 times brighter than what Goldstone can produce observing on its own.