Experts estimated the closest it got to earth was 202-thousand miles away, at about 3:30 Tuesday afternoon.
If it hit, scientists say it could have blasted out a crater four miles across and 17-hundred feet deep and cause a tsunami 70 feet high.
Scientists discovered this asteroid six years ago and have been monitoring it.
Asteroids are leftovers from the formation of the solar system from about four and a half billion years ago.
