The asteroid Apophis will pass closer to Earth than some satellites in 2029

On April 13, 2029, an asteroid wide enough to cover several city blocks will sweep past the planet at a distance smaller than the orbits of many communications satellites. The object, named 99942 Apophis, will approach within roughly 20,000 miles of Earth’s surface, close enough to be seen with the naked eye by observers across parts of the world, yet posing no danger of a collision.

How close 2029 will bring it

During the 2029 flyby, Apophis will come to about 32,000 kilometers, or roughly 20,000 miles, from Earth’s surface. That places it nearer than the ring of satellites in geosynchronous orbit, which circle the planet at an altitude of about 36,000 kilometers, or around 22,000 miles. In other words, for a brief stretch the asteroid will pass inside the zone occupied by some of the spacecraft that relay television signals and weather data, as NASA describes on its Apophis mission page.

Such a near miss by an object of this size is rare. Encounters this close involving an asteroid large enough to see without a telescope happen only once every several thousand years on average, making the event a notable opportunity for scientists and skywatchers alike.

The size and shape of the visitor

Apophis measures roughly 340 to 375 meters across, a scale often compared to a large stadium or a cluster of tall buildings. It is a stony asteroid, one of the countless rocky bodies left over from the early solar system that now trace orbits carrying them near Earth’s path around the Sun. Its orbit intersects the region Earth travels through, which is why the two occasionally draw close.

As it slips past in 2029, the asteroid is expected to be visible to the unaided eye from much of Europe, Africa and western Asia, appearing as a moving point of light crossing the night sky. That naked-eye visibility sets the event apart, since most asteroid flybys are detectable only through telescopes.

The name Apophis carries an ominous ring by design. It was drawn from an ancient Egyptian figure associated with chaos and darkness, a fitting label for an object that briefly stirred concern after its discovery. That early reputation, combined with its size and the closeness of the 2029 approach, is part of why the asteroid has attracted so much public attention compared with the many smaller rocks that pass near Earth each year.

Why there is no cause for alarm

When Apophis was discovered in 2004, early calculations could not immediately rule out a future impact, and for a time it ranked among the more closely watched near-Earth objects. Continued tracking and refined orbital analysis have since removed that concern. Astronomers have determined that Apophis poses no risk of striking Earth for at least a century, effectively clearing the 2029 pass and the decades that follow.

The reassurance rests on precise measurements of the asteroid’s path. Radar observations and optical tracking have tightened the predictions of where Apophis will be, allowing scientists to project its motion far into the future. The European Space Agency’s planetary defense office, which monitors hazardous objects, provides its own assessment of the asteroid on its Apophis page.

A natural experiment for planetary science

Rather than a threat, the 2029 encounter offers a chance to study an asteroid at unusually close range. Earth’s gravity will tug on Apophis as it passes, and researchers want to learn whether that gravitational stress can alter the object, potentially triggering landslides on its surface, shifting its rotation, or subtly changing its shape. Watching how a rubble-strewn body responds to such a close gravitational encounter would sharpen models of asteroid structure and behavior.

Those insights feed directly into planetary defense. Understanding how asteroids are built, how they spin and how they react to outside forces informs any future effort to deflect an object that might one day be on a collision course. Apophis, by passing so close while posing no danger, delivers that information without the stakes of an actual threat.

A spacecraft waiting to greet it

NASA plans to study the asteroid up close with a repurposed spacecraft. After delivering a sample of the asteroid Bennu to Earth in 2023, the OSIRIS-REx probe was redirected toward Apophis and renamed OSIRIS-APEX. The spacecraft is set to reach the asteroid in late June 2029, shortly after the April flyby, and will spend time surveying its surface and measuring any changes caused by the close pass with Earth. Additional background on the asteroid is available through NASA’s Apophis facts overview.

Together, the naked-eye flyby and the follow-up mission promise a detailed look at an object that once inspired worry and now serves as a scientific prize. When Apophis threads between Earth and its outermost satellites in 2029, it will offer a vivid demonstration that a close approach can be an occasion for discovery rather than fear.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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