Asteroid Apophis to Pass Earth on April 13, 2029
The 340-meter asteroid will fly 19,400 miles above Earth, offering a rare opportunity for planetary science missions.
Updated on Oct. 24, 2026 in Space
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Asteroid 99942 Apophis is set to pass just 19,400 miles from Earth on April 13, 2029. This event offers a rare chance to observe how terrestrial gravity alters the path and surface of a 340-meter asteroid.
Why it matters
Scientists plan to use the close flyby to study the physical effects of Earth's gravity on the asteroid. Because an object of this size only passes this near every 5,000 to 10,000 years, the encounter provides a unique natural laboratory for planetary defense research.
The 340-meter asteroid will pass well within the 22,236-mile altitude of geostationary satellites. Researchers will utilize tools including the 12U-sized LUMIO CubeSat to monitor the object during this rare encounter.
The players
NASA
The United States government agency responsible for the nation's civilian space program and aeronautics research.
European Space Agency
An international organization with 22 member states dedicated to the exploration of space and space science.
OSIRIS-APEX
A NASA spacecraft mission repurposed from its previous identity as OSIRIS-REx to study asteroid Apophis.
RAMSES
A European Space Agency mission designed to rendezvous with and observe the asteroid during its 2029 flyby.
LUMIO
A CubeSat mission tasked with detecting flashes caused by meteoroid impacts on the lunar surface.
The details
Multiple missions, including the European Space Agency's RAMSES and NASA's OSIRIS-APEX, will monitor the asteroid to gather data on its physical state. The flyby will be visible to the naked eye from regions across Europe, Africa, Asia, Australia, and eastern South America.
Timeline
2004: Discovery of asteroid Apophis.
2021: Astronomers officially ruled out an Earth impact for 2029.
2023: NASA's OSIRIS-REx returned samples from asteroid Bennu.
2028: Scheduled launch of the RAMSES and LUMIO missions.
April 13, 2029: Apophis reaches its closest approach to Earth.
The Big Picture
This event serves as a pivotal test for NASA's planetary defense research by providing real-world data on near-Earth object behavior. It marks a departure from theoretical modeling, offering a rare look at how gravitational forces influence large asteroid trajectories.
For the general public, the asteroid will be visible to the naked eye in 2029 across much of the Eastern Hemisphere. This event also helps scientists refine tracking models for future near-Earth objects that could one day pose a security threat.
The takeaway
The 2029 flyby of Apophis represents a historic scientific opportunity to observe an asteroid at close range without launching a dedicated landing mission. Amateur astronomers and the public can prepare to witness the event, as the asteroid is expected to be bright enough for naked-eye viewing.
What happens next
The RAMSES and LUMIO missions are scheduled to launch in 2028 ahead of the April 2029 close approach.
Further reading
Learn more about upcoming missions and celestial events on the Space section page.
Source note: This article includes information reported by Forbes.
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