On a spring evening in 2029, an asteroid roughly the size of a large stadium will sweep past Earth so closely that it will slip beneath the ring of satellites that supply weather forecasts and television. The object is Apophis, named for an ancient Egyptian god of chaos, and its approach on April 13, 2029, will bring it within about 32,000 kilometers of the surface, closer than the highest-flying communications satellites orbit. It will be visible to the naked eye from parts of Earth, a rare chance to watch a space rock streak by.
Despite the ominous name and the dramatic proximity, Apophis will not hit the planet. Astronomers have tracked it closely enough to rule out an impact for at least the next century. What remains is a once-in-a-generation scientific opportunity to watch Earth’s gravity reach out and physically alter an asteroid in real time.
A closer pass than the weather satellites
The most striking fact about the 2029 flyby is its distance. Geostationary satellites, including many weather and communications platforms, orbit at roughly 35,786 kilometers above the equator, so as Apophis passes at about 32,000 kilometers it will briefly be nearer to Earth’s surface than that entire satellite ring. For an object of its size, this is the closest predicted approach scientists have ever been able to forecast far in advance.
That distance is still comfortably beyond the atmosphere and the orbits of most active spacecraft, and the asteroid’s path is inclined so that it does not thread through the crowded equatorial belt where geostationary satellites sit. There is no meaningful risk of a collision with orbiting hardware.
Passing that near, and being a few hundred meters across, Apophis will be bright enough to see without any equipment, which is extraordinarily rare for an asteroid. Most near-Earth objects remain faint points visible only through telescopes, but this one will briefly resemble a moderately bright star drifting against the constellations over the course of an evening. For skywatchers it will be a chance to watch a chunk of the early solar system move across the sky in real time.
How big Apophis actually is
Apophis measures roughly 340 meters across, large enough that it once ranked among the more worrying near-Earth objects when it was first discovered. Early observations in the mid-2000s could not immediately exclude a future impact, and for a time the asteroid held an unusually high place on hazard scales. Additional tracking steadily shrank the uncertainty until the danger was eliminated.
Refined orbital measurements, including radar observations, allowed astronomers to map its trajectory decades into the future and formally remove it from the risk list. The 2029 encounter that once caused concern is now anticipated as a purely observational event.
The one lingering worry after 2029 was a phenomenon known as a gravitational keyhole, a small region of space that, if the asteroid passed through it, could have bent its path toward an impact years later. Precise tracking has since shown that Apophis will miss those keyholes, closing off the scenarios that had kept it on watch lists. That is why agencies now speak of the flyby with anticipation rather than caution, treating it as a scheduled opportunity instead of a threat to be managed.
What Earth’s gravity will do to the asteroid
Passing so close, Apophis will feel Earth’s gravity strongly enough to change it. The planet’s pull is expected to tweak the asteroid’s orbit and may also stress its structure, potentially triggering small landslides, shifting surface material, or subtly altering how it tumbles through space. Studying those changes offers a natural experiment no laboratory could reproduce, revealing how a rubble-pile asteroid responds to a powerful gravitational squeeze.
To capture it, NASA is repurposing the spacecraft that returned a sample from asteroid Bennu, redirecting it under the name OSIRIS-APEX to rendezvous with Apophis after the flyby and inspect whatever the encounter changed. The European Space Agency is also planning a mission to study the asteroid before and during the close pass, giving scientists complementary vantage points on the same rare event.
A dress rehearsal for planetary defense
Beyond the immediate science, the 2029 approach doubles as practice for the broader task of tracking and understanding potentially hazardous objects. Watching a known asteroid interact with Earth’s gravity, and testing whether predictions of its behavior hold up, sharpens the tools that planetary defense would rely on if a genuinely threatening object were ever found.
For most people, though, Apophis will simply be a moving point of light crossing the sky, an asteroid that came remarkably close and passed harmlessly by. The viewing geography favors the Eastern Hemisphere, with observers across Europe, Africa and western Asia best placed to follow the asteroid as a slow-moving star, bright enough to track without a telescope under dark skies. According to planetary scientists, up to a large share of the world’s population will be positioned to glimpse it, turning what was once a source of worry into one of the most anticipated sky-watching events of the coming decade.
This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.
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