The short answer: no. Apophis will not hit Earth in 2029, and NASA's current calculations rule out an impact for at least the next century. But the longer answer is more interesting, because Apophis was once one of the most feared asteroids ever found.
Apophis was discovered in June 2004. Within months, early orbit calculations, based on only a few days of observations, showed a small but real chance of an impact on April 13, 2029. At one point it reached level 4 on the Torino Scale, the highest rating any asteroid has received. Level 4 means "close encounter with a 1% or greater chance of a collision capable of regional devastation."
That number was not a prediction. It was a measure of uncertainty. When an asteroid is first found, astronomers know its path only roughly. As more observations come in, the uncertainty shrinks and risks almost always drop to zero.
The old worry was about a "gravitational keyhole": a tiny region of space that Apophis could pass through in 2029. If it did, Earth's gravity would bend its path just enough to set up a collision on a later pass. Measurements show Apophis will miss the keyhole, so that scenario is off the table.
Apophis is affected by the Yarkovsky effect, a very slight thrust caused by the way a rotating asteroid absorbs sunlight and radiates heat. It is tiny, but it adds up over years. Scientists include it in their models, and the 2029 flyby will give them a rare chance to measure it more precisely.
The flyby itself will also change Apophis. Earth's gravity will alter its orbit and may change its spin and shape. After 2029, astronomers will re-calculate its path, but nothing suggests the outcome will bring a threat.
Orbit predictions are not guesses. Astronomers measure an asteroid's position in the sky many times over months and years. Each measurement tightens the range of possible paths. They then run computer models that include the gravity of the Sun, the planets and the Moon, and small forces such as the Yarkovsky effect. Independent teams, including NASA's Center for Near Earth Object Studies and European groups, run these calculations separately and compare the results. When different teams reach the same answer, confidence rises.
Radar is especially powerful. By bouncing radio waves off an asteroid, scientists can measure its distance and speed to a precision that optical telescopes cannot match. The radar observations of Apophis played a major role in clearing the 2036 and 2068 questions.
Could the risk come back? Orbits can be refined, but a hit is not a hidden possibility. After 2029, astronomers will measure the new orbit again, and the risk will be reassessed as a matter of routine.
Do we need to deflect Apophis? No. There is no threat to deflect. The 2029 flyby is a chance to study a large asteroid up close instead.
Apophis will pass about 32,000 km above Earth's surface. That is close for its size, but far from a collision. It will not cause earthquakes, tides or any noticeable effect on Earth. Learn more in our complete Apophis guide.
Apophis is a case study in how planetary defense works: find the object, track it, and let the numbers settle. The scary headlines of 2004 turned into a safe, spectacular flyby, and a great scientific opportunity. See also: how humanity learned to move an asteroid.
Facts in this article are drawn from public scientific sources. For primary information, see: