This updated set of images of the Halloween asteroid released yesterday. Very nice detail for radar images. Be sure to click the image above for a larger version.
Asteroid 2015 TB145 is depicted in eight individual radar images collected on Oct. 31, 2015 between 5:55 a.m. PDT (8:55 a.m. EDT) and 6:08 a.m. PDT (9:08 a.m. EDT). At the time the radar images were taken, the asteroid was between 440,000 miles (710,000 kilometers) and about 430,000 miles (690,000 kilometers) distant. Asteroid 2015 TB145 safely flew past Earth on Oct. 31, at 10:00 a.m. PDT (1 p.m. EDT) at about 1.3 lunar distances (300,000 miles, 480,000 kilometers).
To obtain the radar images, the scientists used the 230-foot (70-meter) DSS-14 antenna at Goldstone, California, to transmit high power microwaves toward the asteroid . The signal bounced of the asteroid, and their radar echoes were received by the National Radio Astronomy Observatory’s 100-meter (330-foot) Green Bank Telescope in West Virginia. The images achieve a spatial resolution of about 13 feet (4 meters) per pixel.
Image Credit: NASA/JPL-Caltech/GSSR/NRAO/AUI/NSF