Discovered in 2004, 99942 Apophis is an asteroid with an estimated diameter of about 1,066 feet. This near-Earth object was originally given a 2.7 percent chance of a collision with Earth in 2029. However, subsequent calculations showed that there is no risk of impact in that year.
On April 13, 2029, Apophis will come within 19,400 miles of the Earth and will be the closest an asteroid of that size has come to impacting Earth in recorded history. The asteroid will also make another near-Earth approach in 2036, and scientists estimate that the chance of collision in that year is less than one in 1 million.