A Once-in-a-Lifetime Approach
On April 13, 2029, an asteroid roughly 370 meters across will pass within 32,000 kilometers of Earth — closer than many of the geostationary satellites in our orbit. The event will be visible to the naked eye across Europe, Africa, and parts of Asia, making it the first asteroid large enough to be seen without optical aid to pass this close to Earth in recorded human history.
The asteroid is called Apophis, named after the Egyptian god of chaos. When it was first discovered in 2004, preliminary calculations suggested a small but alarming probability that it could strike Earth in 2029 or 2036. Further observations eventually ruled out both impact scenarios, and Apophis was removed from hazard lists. But the legacy of those initial alarm bells and the asteroid's extraordinary upcoming close approach have made it one of the most studied — and now most visited — small bodies in the solar system.
New reports confirm that the encounter has attracted not just government space agencies but private companies with plans to land on the surface. Multiple spacecraft, including landers, are expected to accompany Apophis during its flyby, making this potentially the first time a privately-developed spacecraft has attempted to land on an asteroid during a close Earth approach.
Who Is Going to Apophis
Several missions are already in development or planning phases targeting the 2029 flyby. OSIRIS-APEX, a NASA mission reusing the spacecraft that returned samples from asteroid Bennu in 2023, is already en route to Apophis and will rendezvous with the asteroid before its close approach, spending approximately 18 months studying the surface and conducting active operations.
The European Space Agency's Ramses mission (Rapid Apophis Mission for Space Safety) was approved in late 2024 specifically to study how the tidal forces of Earth's gravity during the close approach alter the asteroid's structure, rotation, and surface. ESA scientists hope that Ramses data will provide insight into how planetary flybys reshape small solar system bodies — processes relevant to understanding both asteroid behavior and the history of the solar system.
The private entrant adds a new dimension. A commercial company has announced plans to deploy a lander on Apophis's surface during or around the time of the close approach, a technically demanding mission given the asteroid's low gravity, rough terrain, and uncertain surface composition. Apophis is estimated to have a surface gravity roughly 100,000 times weaker than Earth's — making landing more akin to docking with a slow-moving object than setting down on a planet.
What Makes Apophis Scientifically Extraordinary
Even before the first spacecraft arrives, Apophis has already contributed to science. Ground-based observations have allowed astronomers to constrain its composition, likely a chondrite-type stony asteroid, measure its spin rate, and model the Yarkovsky effect — the subtle push of thermal radiation that causes small asteroids to drift from their predicted trajectories over time.
The 2029 flyby will allow scientists to observe something that has never been directly measured: the tidal deformation of an asteroid under the gravitational influence of a planet. At its closest approach, Apophis will experience tidal forces significant enough to potentially cause landslides, reshape the surface regolith, and possibly crack the interior. These are not theoretical concerns — radar observations suggest Apophis may have a rubble-pile structure, an aggregate of smaller rocks loosely bound by gravity rather than a monolithic solid, making it especially susceptible to tidal reshaping.
The data gathered by orbiting and landed spacecraft during the flyby could answer fundamental questions about how rubble-pile asteroids form, evolve, and respond to gravitational perturbations. This matters not just for scientific curiosity but for planetary defense: understanding how asteroids respond to close encounters helps engineers model how to deflect or disrupt an asteroid that actually poses an impact threat.
The Planetary Defense Dimension
Apophis itself poses no impact threat for at least the next century according to current models. But the massive campaign of observations and missions converging on its 2029 flyby reflects how seriously the planetary defense community now takes near-Earth objects — and how much the field has matured since the chaotic days of the 2004 panic.
NASA's DART mission successfully deflected asteroid Dimorphos in 2022, demonstrating for the first time that kinetic impactors can meaningfully alter an asteroid's orbit. ESA's Hera mission, launched in 2024, is now surveying the aftermath of that impact in detail. Apophis 2029 represents a different kind of test: an opportunity to observe a large asteroid up close under the influence of natural gravitational forces, providing data that no laboratory or small-scale mission can replicate.
- Apophis will be visible to the naked eye during its April 2029 flyby — the first such event in modern history
- At least three missions are targeting the encounter: NASA's OSIRIS-APEX, ESA's Ramses, and at least one private lander
- Tidal deformation during the flyby may reshape the asteroid's surface and reveal its internal structure
For the billions of people who will be able to look up and see Apophis crossing the sky — roughly the angular size of a moving star — it will be a reminder that the solar system is dynamic, that space is not empty, and that the line between safe and catastrophic is thinner than comfortable assumptions suggest.
This article is based on reporting by New Scientist. Read the original article.
