How Astronomers Missed the Massive Asteroid That Just Whizzed Past Earth

By Yasemin Saplakoglu A large asteroid just whizzed past our planet — and astronomers weren’t expecting it. Ranging in size from 187 to 427 feet (57 to 130 meters) wide, the space rock named 2019 OK snuck up on us Thursday morning (July 25). It swung as close as 45,000 miles (73,000 kilometers) from Earth, …