A newly-discovered asteroid, designated 2018 DU, made a close pass to the Earth over the weekend, coming within 280,000 kilometers (174,000 miles) of the planet on February 25. The ten-meter (33-foot) rock is the 17th known asteroid to have passed within the Moon’s orbit this year.

2018 DU wasn’t spotted until February 23, two days before its close approach, due to its small size–less than half of the size of the meteor that exploded over Chelyabinsk, Russia, in 2013. It was first spotted by the Virtual Telescope Project (VTP), through the Rome-based organization’s Tenagra III telescope in Arizona. Although VTP made the 10-meter size estimate, the International Astronomical Union’s Minor Planet Center says that 2018 DU could be as small as 4 meters (13 feet).

This is the 17th known near-Earth object to have passed within the Moon’s orbit this year, marking a notable increase in the number of close passes being made, including asteroid 2017 AG13’s January 9 flyby, and 2017 BX’s close pass fifteen days later.