Just a month ago, astronomers at NASA didn't know 2015 TB145 existed. Now the space agency is offering close-ups of the asteroid, UPI reported. On Halloween, 2015 TB145 made its closest approach to Earth. Its trajectory sent it within 1.3 Earth-lunar distances, passing by on the other side of the moon, approximately 300,00 miles. During its flyby, Earthbound radio telescopes bounced microwaves off the face of the asteroid, revealing its size, shape and texture. On Tuesday, NASA shared the images online. The space rock is plainly spherical and measures 2,000 feet in diameter. "The radar images of asteroid 2015 TB145 show portions of the surface not seen previously and reveal pronounced concavities, bright spots that might be boulders, and other complex features that could be ridges," Lance Benner, head of asteroid radar observations at NASA's Jet Propulsion Laboratory, said in a press release. "The images look distinctly different from the Arecibo radar images obtained on October 30 and are probably the result of seeing the asteroid from a different perspective in its three-hour rotation period." The latest images were created by pointing the DSS-14 antenna at Goldstone, Calif., in the direction of the asteroid and blasting high-powered microwaves. The rebounding waves were fielded by the National Radio Astronomy Observatory's Green Bank Telescope located in West Virginia. "Working with our observatory partners, we were able to get our resolution down to less than 13 feet per pixel," said Shantanu Naidu, a postdoctoral student at the Caltech and a member of JPL's radar team. "It is a truly remarkable achievement -- one which we will later be able to apply when future flyby opportunities present themselves." The asteroid's orbit will bring 2015 TB145 back toward Earth in September 2018. In the meantime, JPL and its asteroid-seeking scientists will keep looking for other unidentified near-Earth objects.