The number of discovered near-Earth asteroids (NEAs) now tops 15,000, with an average of 30 new discoveries added each week. The number of discovered near-Earth asteroids (NEAs) now tops 15,000, with an average of 30 new discoveries added each week. This milestone marks a 50 percent increase in the number of known NEAs since 2013, when discoveries reached 10,000 in August of that year. Surveys funded by NASA’s Near Earth Object (NEO) Observations Program (NEOs include both asteroids and comets) account for more than 95 percent of discoveries so far. The 15,000th near-Earth asteroid is designated 2016 TB57. 2016 TB57 is a rather small asteroid — about 50 to 115 feet (16 to 36 meters) in size — that will come closest to Earth on Oct. 31 at just beyond five times the distance of the moon. It will safely pass Earth. Read more