CONTACT BINARY ASTEROID: When mountain-sized asteroid 2014 JO25 flew past Earth on April 19th, it looked like a fast-moving speck of light in backyard telescopes. NASA radars saw much more. The 70-meter antenna at Goldstone CA pinged the asteroid, illuminating it with radio energy as it passed by. The resulting images reveal a peanut-shaped asteroid that rotates about once every five hours:
"The asteroid has a contact binary structure - two lobes connected by a neck-like region," says Shantanu Naidu, a scientist from NASA's Jet Propulsion Laboratory in Pasadena, California, who led the Goldstone observations. "The largest of the asteroid's two lobes is about 2,000 feet (620 meters) across."
These images have a resolution as fine as 25 feet (7.5 meters) per pixel. Additional radar observations are being conducted at both Goldstone and Arecibo on April 20 and 21, and could provide even greater detail. Stay tuned!