For many years, Apophis was considered the most dangerous known asteroid. Astronomers calculated it had a small chance of hitting our planet either in 2029 or, if that was a miss, in 2036. More precise observations of its orbit over the years have shown that it will actually come as close as 40,000 kilometers to Earth in 2029 but will definitely miss us – as long as a natural collision between Apohis and another passing object doesn't change its orbit. Astronomers have now calculated what that risk is.
For those on Team Asteroid, you should know that a 335-meter (1,100-foot) object such as Apophis wouldn’t send us the way of the dinosaurs. It would create vast devastation though and for this reason, scientists remained alert and curious about the possibilities. On April 13, 2029 (yes, a Friday 13th), Apophis will get just 37,399 kilometers (23,240 miles) from Earth. A little nudge from another object between now and then might create a large deviation in the future. After all, when NASA's DART mission redirected asteroid Dimorphos, it demonstrated just that (as well as completely changing its shape).
“Given how closely Apophis will pass Earth, there is a possible risk that a deflection from its current trajectory may move Apophis closer to impacting us,” co-author Benjamin Hyatt, an undergraduate student at Waterloo University, said in a statement. “Hypothetically, another asteroid colliding with Apophis could cause such a deflection, motivating us to study this scenario, however unlikely it may be.”