The asteroid was only discovered Sunday due to its size.
To be honest, that's a sketchy report. Space.com has more details in Watch Big Asteroid Buzz Earth This Weekend: 2 Live Webcasts.
An asteroid the size of a city block is due to make a close pass by Earth on Saturday (March 9), and you can get a front-row view via two back-to-back webcasts.The article notes why people, as exemplified by the WCPO clip, are interested in this event.
The asteroid 2013 ET was discovered March 3 by the Catalina Sky Survey based at the University of Arizona. During the flyby, the space rock will fly within 2.5 times the moon's distance from Earth. On average, the moon is about 238,000 miles (about 383,000 kilometers) from Earth.
Asteroid 2013 ET is about 210 feet by 460 feet (64 meters by 140 m) in size, with some astronomers comparing its width to a football field. Its close approach to Earth comes just days after another space rock, the 33-foot (10 meters) asteroid 2013 EC, buzzed the Earth on Monday (March 4) at a range just inside the moon's orbit.
This asteroid pass comes less than a month after two major space rock events: the close flyby of asteroid DA14 near Earth, and the impact of a meteor into Russia. And 2013 ET's approach comes just days after the asteroid 2013 EC flew within 230,000 miles (370,000 km) of Earth early Monday.Keep up the good work. Maybe one day, the U.N. will do something about space rocks the way it is now doing something about space weather.
"The recent flurry of asteroidal close calls and near misses, including the double whammy of DA14 and the Siberian meteor on February 15, is starting to make our region of space seem like a video game or pinball contest," astronomer Bob Berman, columnist and contributing editor of Astronomy magazine, said in a statement. "This latest interloper arrives just as serious debates are unfolding as to the obvious need for more and better monitoring of potentially hazardous asteroids crossing our orbit — and even whether we should develop a 'deflection' system."