Massive Asteroid the Size of Chrysler Building to Pass Earth Today On 2/1/21 at 10:03 AM EST A huge asteroid will zoom past Earth today, data from NASA's Center for Near Earth Studies (CNEOS) shows. The space rock, dubbed 2016 CL136, is set to make its closest approach to our planet at 5:26 p.m. on February 1, according to CNEOS. Based on its observed magnitude, astronomers estimate that the asteroid could measure anywhere between around 460 feet and 1,017 feet in diameter. Read more At the upper end of this estimate, the space rock would be around the same size as the Chrysler Building in New York City or the Eiffel Tower in Paris, France.