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Asteroid Apophis, a 375-meter-wide space rock once thought to threaten Earth, will pass closer than some satellites on April 13, 2029. The approach, at about 32,000 kilometers, will be visible to the naked eye from parts of Europe, Africa, and western Asia. NASA and other agencies confirm it poses no risk, but the close flyby offers a rare chance for scientists to study its surface, structure, and orbit in detail.
Apophis will be the largest asteroid to pass this close in history. Its path will take it just below geostationary satellite orbits, creating a bright, fast-moving point of light in the night sky. Observers in the Eastern Hemisphere will have the best view without telescopes or binoculars. Researchers aim to measure its spin, composition, and surface features during the event.
Earlier calculations suggested possible impacts in 2029, 2036, and 2068, raising fears that Apophis could be a “planet killer.” Updated data from NASA’s tracking programs have ruled out any chance of collision for at least the next century. A study by astronomer Paul Wiegert notes a very small chance that a collision with another asteroid could alter its course, but the probability of a 2068 impact remains about one in 150,000.
Is Apophis a planet killer?
With all impact risks removed for over a century, Apophis is not considered a planet killer. While its unusual orbit once caused concern, scientists now agree the asteroid will pass safely by Earth in 2029 and 2036.
What would happen if Apophis hit Earth?
If Apophis struck Earth, the damage would be regional but severe. The Planetary Society estimates the energy released would equal about 1,200 megatons of TNT. Such an event could cause strong earthquakes, widespread fires from heat and debris, and, if it hit the ocean, massive tsunamis.
Discovery of asteroid Apophis
Apophis was discovered in 2004 at Arizona’s Kitt Peak Observatory by Roy Tucker, David Tholen, and Fabrizio Bernardi. Initial tracking placed it among the most dangerous known asteroids, but improved observations over the years proved those early predictions wrong. By 2021, new measurements confirmed it will not impact Earth in the foreseeable future.
Structure and formation
The asteroid is made of silicates mixed with iron and nickel, with a peanut-like shape consisting of two lobes. It originated in the main asteroid belt between Mars and Jupiter before being moved into its current orbit by gravitational interactions.
Dimensions and details
Apophis spins once every 30 hours and completes an orbit around the Sun in 324 days. Its 2029 path will take it near satellite altitudes, but the likelihood of hitting one is extremely small. The best viewing will be from Europe, Africa, and western Asia.
Where does the name Apophis come from?
The name comes from Apophis, the Greek form of Apep, an ancient Egyptian deity representing chaos and an enemy of the sun god Ra. The name reflects the asteroid’s once-feared potential.
Future missions to study Apophis
NASA has adapted its OSIRIS-REx spacecraft into OSIRIS-APEX, which will rendezvous with Apophis after the 2029 flyby. The probe will orbit for 18 months, map the asteroid, and use bursts of gas to expose subsurface material.
The European Space Agency is also developing Ramses, a mission planned for a 2028 launch if approved in 2025. Ramses would accompany the asteroid during its close approach, deploying CubeSats for additional data.
