A newly discovered asteroid more than 200 feet wide will zoom in between Earth and the moon Saturday afternoon in an occurrence NASA says happens only once a decade. 

The asteroid, 2023 DZ2, was discovered in February by astronomers at the observatory of La Palma in the Canary Islands, Spain, according to EarthSky. Since then, astronomers have continued to observe the asteroid to get a better idea of its size and orbit. NASA says the asteroid could be anywhere from 134 to 305 feet in diameter.

The asteroid is expected to pass the Earth at about 100,000 miles away – about half the distance to the Moon – at about 3:51 p.m. EDT, NASA said Saturday on Twitter.