The asteroid came just over 13,000 miles from Earth, well below many communications satellites orbiting the planet, scientists said. The closest approach was to take place Thursday morning over the southeastern Pacific Ocean.
Scientists estimated the asteroid to be between 15 and 30 feet in diameter – the size of a school bus, according to some press reports. By asteroid standards, it’s considered puny. Asteroids this size hit Earth’s atmosphere and burn once a year or two, said Paul Chodas, director of the Center for Near-Earth Object Studies at NASA’s Jet Propulsion Laboratory. There could be as many as 100 million of these little asteroids out there.
The real threat is posed by considerably larger asteroids. The good news is that these are easier to spot much earlier than a few days.
Asteroid 2020 SW, as it is known, was discovered last Friday by the Catalina Sky Survey at the University of Arizona at Tucson.