While tracking the asteroid, which is named after the Egyptian god of chaos, scientists found it has sped up due to an orbital process called the Yarkovsky effect.
“The new observations we obtained with the Subaru telescope earlier this year were good enough to reveal the Yarkovsky acceleration of Apophis,” University of Hawaii astronomer Dr. David Tholen said in a statement. “[T]hey show that the asteroid is drifting away from a purely gravitational orbit by about 170 meters per year, which is enough to keep the 2068 impact scenario in play. Small, but non-zero.” He also noted that even without the acceleration, “Apophis is still a threatening object, just not in 2068.”
Per Gizmodo, the Palermo Technical Impact Hazard Scale "suggests there’s a 1 in 150,000 chance of Apophis hitting Earth on April 12, 2068."
According to the report, Apophis—which Tholen and his team discovered in 2004—is slated to pass the Earth in 2029 as well. Their research reveals that while it won’t hit our planet then, the large asteroid will come very close during its April 13, 2029 approach, instead passing between Earth and a network of communication satellites. It’ll also be visible to the unaided eye.
While astronomers previously dismissed the likelihood that it could crash into our planet, calculations show that we can’t eliminate that option. The asteroid’s orbit has shifted due Yarkovsky effect. This acceleration happens because “asteroids absorb sunlight as they tumble through the solar system,” Popular Mechanics writes. “In order to maintain thermal equilibrium, an asteroid will emit that solar energy as heat. This generates a force that causes them to speed up and, in turn, change the asteroid's orbit.”
NASA and various space agencies are always surveying possibly risky objects for these sorts of orbit-shifting effects.