Have you ever stared at the stars and wondered about the giant rocks speeding through space? One of the most famous of these is the Apophis asteroid. It captured the world’s attention because early predictions suggested it might collide with Earth. Its name comes from an ancient Egyptian god of chaos, a serpent-like monster that tried to swallow the sun each night. The dramatic name fit perfectly, especially when scientists originally believed it had a small but real chance of striking our planet.
But here’s the good news: as of November 2025, experts say the Apophis asteroid will not hit Earth for at least a century. It remains an object of high interest, but not high danger. This article explores what Apophis is, how it was discovered, what it looks like, how close it will come, what would happen if it ever hit Earth, and why it matters to science—and we’ll keep the explanations simple and clear.
The Discovery of Apophis
The Apophis asteroid was discovered on June 19, 2004, by astronomers Roy Tucker, David Tholen, and Fabrizio Bernardi. Using a telescope at Kitt Peak National Observatory in Arizona, they spotted a faint moving object among the stars. At first, they labeled it with a temporary designation: 2004 MN4. Only later, in 2005, did it receive its official name: 99942 Apophis.
The astronomers chose “Apophis” because the asteroid’s unpredictable early orbit reminded them of the Egyptian god of chaos. Some fans noticed that Apophis is also the name of a villain in the TV show Stargate SG-1, but the discoverers say that was simply a fun coincidence.
When the Apophis asteroid was first discovered, it didn’t seem particularly unusual. But soon after, computer models showed something shocking: the asteroid had a small chance—about 2.7%, or nearly 3 in 100—of hitting Earth in 2029. That made Apophis the highest-risk asteroid ever recorded at the time, earning a ranking of 4 on the Torino Scale, which measures asteroid danger.
News stories exploded. Scientists received constant questions. Nicknames like the “God of Chaos asteroid” spread online.
Fortunately, more observations changed everything. By 2006, better data proved Apophis would safely miss Earth in 2029.
What Does the Apophis Asteroid Look Like?
The Apophis asteroid isn’t round like a planet. Instead, it has a lumpy, stretched shape—something between a peanut and a potato. Its longest dimension is about 450 meters (1,480 feet), while its shortest is around 170 meters (560 feet). On average, scientists describe it as a roughly 340–375 meter-wide object—about the size of three or four football fields laid side by side.
Apophis is extremely heavy, weighing around 61 million metric tons. It belongs to a class called stony asteroids, made mostly of rock, nickel, and iron. Radar images taken in 2012 and 2021 revealed a rough, uneven surface covered in boulders and debris.
Another interesting detail: Apophis spins slowly. It completes one full rotation in roughly 30 hours, and it doesn’t spin smoothly—it tumbles slightly, like a football thrown off-balance. This wobble makes its orientation tricky to predict, so scientists rely on radar and reflected sunlight measurements to refine its motion.
The Apophis asteroid likely originated in the asteroid belt between Mars and Jupiter, but gravitational interactions nudged it into a path that crosses Earth’s orbit. This makes it a near-Earth asteroid—a space rock that occasionally passes close to our planet.
Apophis’s Journey Around the Sun
Apophis orbits the Sun in an elongated path that takes about 324 days, slightly shorter than Earth’s 365-day year. This places it in the Aten group of asteroids, which have orbits mostly inside Earth’s own orbit.
While the Apophis asteroid comes near Earth from time to time, most flybys are distant and harmless. One upcoming flyby, however, is extraordinary.
The 2029 Flyby: A Once-in-a-Lifetime Event
On April 13, 2029, the Apophis asteroid will pass only 31,600 kilometers (19,600 miles) from Earth’s surface—closer than many satellites. For comparison, GPS satellites orbit around 20,200 kilometers above Earth, meaning Apophis will sweep beneath them.
This event will be visible from parts of Europe, Africa, and Western Asia, where the asteroid may appear as a slowly moving point of light bright enough to see without a telescope.
During this close pass, Earth’s gravity will tug at Apophis, slightly altering its orbit. The encounter may shake its surface, causing small landslides or “asteroid quakes.” Scientists expect this to reveal fresh material and help them understand how rubble-pile asteroids react to gravitational forces.
After 2029, Apophis will return in 2036, but much farther away. Earlier concerns about a potential 2068 impact have now been ruled out. According to NASA, the asteroid poses no known threat for at least 100 years.
What Would Happen If the Apophis Asteroid Hit Earth in 2029?
Even though a collision is not expected, it’s worth exploring what such an impact would mean.
Apophis would release energy equivalent to more than 1,000 megatons of TNT—over 1 billion tons of explosive force. This is thousands of times more powerful than the largest nuclear weapon ever tested.
If it hit land:
- A crater around 5 kilometers (3 miles) wide would form.
- Everything within hundreds of kilometers would be destroyed.
- Shock waves would shatter windows and collapse weak structures far beyond the crater.
- Fires could ignite from the intense heat.
- Dust and debris would darken the sky temporarily.
If it struck the ocean:
- Massive tsunamis could rise hundreds of meters high.
- Coastlines could be devastated across entire regions.
Still, Apophis is not large enough to cause a global extinction like the 10-kilometer asteroid that ended the age of dinosaurs 66 million years ago.
Early models—back when scientists still thought a 2029 impact was possible—showed potential paths of destruction over the Pacific Ocean, Russia, Central America, and other regions. Today, since the chance of impact is essentially zero, these scenarios are now academic.
How Scientists Watch and Study the Apophis Asteroid
NASA, the European Space Agency (ESA), and observatories worldwide track Apophis using telescopes and radar. The Goldstone Solar System Radar in California provided some of the clearest images and path measurements in 2021, confirming that the asteroid is not a threat.
The most exciting future research will come from spacecraft.
OSIRIS-APEX Mission
NASA’s OSIRIS-APEX spacecraft—formerly OSIRIS-REx, which returned samples from asteroid Bennu—will rendezvous with Apophis shortly after the 2029 flyby. It will:
- Orbit the asteroid for about 18 months
- Map its surface in detail
- Measure how the Earth flyby changed its rotation and structure
- Potentially use thrusters to blow dust off the surface for analysis
ESA has discussed joining the effort with a proposed mission called Ramses, though its status remains undecided.
These missions do more than study Apophis—they help prepare humanity to protect Earth from future threats. Techniques such as NASA’s successful DART mission in 2022, which knocked a small asteroid off course, may one day be used to steer dangerous objects away from Earth.
Why the Apophis Asteroid Matters
Apophis is one of the best examples of how planetary defense works in real life. It shows that:
- Asteroid threats can be identified early.
- Better observations can dramatically change predictions.
- International cooperation matters for space safety.
- Close flybys give scientists rare opportunities to learn.
Apophis also reminds us that space is dynamic and full of surprises. Thousands of near-Earth asteroids exist, and even though most are harmless, understanding them helps us protect our planet and uncover clues about the history of the Solar System.
As we move toward the historic 2029 flyby, scientists continue to study how Apophis might react—will rocks shift, will its spin change, will dust rise? These questions make Apophis not just a once-dangerous asteroid, but a scientific treasure.
So next time you look up at the night sky, remember that the so-called “God of Chaos” is simply passing by—harmless, fascinating, and full of cosmic lessons. Be sure to check out other articles like this on our Astronomy Page.
FAQ: Asteroid Apophis (99942 Apophis)
What is asteroid Apophis?
Apophis is a near-Earth asteroid about 340 meters wide. It follows an orbit that occasionally brings it close to Earth.
Will Apophis hit Earth in 2029?
No. Current observations confirm Apophis will safely pass Earth on April 13, 2029, at about 31,000 km — closer than some satellites but not a collision.
Will Apophis be visible during the flyby?
Yes. Because it passes so close, Apophis will be visible to the naked eye from some regions as a fast-moving point of light.
How close will Apophis get during the 2029 flyby?
It will pass roughly 1/10th the distance to the Moon — closer than many geosynchronous satellites.
What would happen if Apophis ever did hit Earth?
An impact of a 340-meter object would cause regional devastation but not global extinction. However, all current data shows no impact threat.
Why is it named Apophis?
The asteroid was named after the Egyptian serpent deity Apep (Apophis), associated with chaos.