A threatening asteroid called Apophis is expected to come close to Earth in 2029. Scientists have long ruled out that it is at risk of impact, but still want to study it.
Asteroid the size of the Empire State Building will fly past Earth
Asteroid 99942 poses no threat to Earth, but will come close enough to be detected by telescopes and radar.
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- According to predictions, Apophis will fly past the surface of our planet at a distance of 32,000 kilometers on April 13, 2029. Astronomers say the threatening asteroid will fly past us harmlessly.
- Apophis is nearly a quarter mile long—about the size of a cruise ship—and large enough to be visible to the naked eye as it passes Earth.
- Space agencies and science institutes around the world plan to use this rare flyby to study Apophis from the ground using telescopes and even spacecraft.
Among professional and amateur astronomers, no asteroid is more notorious than Apophis.
If you’ve heard of Apophis before, you probably know that after its discovery two decades ago, it was considered a potentially dangerous space boulder that came way too close to Earth. It was originally believed that the asteroid could one day pose a serious threat to our planet.
And one day it might be.
But according to astronomers, that day will not come for another 100 years. Not even in 2029, when Apophis will come closer to Earth than any other asteroid of its size – at least none that scientists knew about in advance.
Thanks to additional observations of Apophis, astronomers have long been able to rule out the risk of an impact in 2029. According to NASA, Apophis will come to a distance ten times closer to Earth than the Moon. Even if the asteroid comes close to Earth again in 2036, it will not hit our planet.
Even though we and our children are safe from the wrath of Apophis, scientists still see a valuable opportunity to study the asteroid as it passes by Earth to learn as much as possible about other space rocks that could actually hit our planet.
Here you can find out everything you need to know about Apophis and how space agencies want to protect the Earth from other asteroids of this type.
Apophis is scheduled to fly past Earth in 2029
According to forecasts, Apophis will fly past the surface of our planet on April 13, 2029, at a distance of 32,000 kilometers.
For the superstitious people: Yes, it is a Friday after all.
On that day, Apophis will come closer than telecommunications satellites in a geostationary orbit, ESA said.
The close encounter with Earth will make the asteroid visible in the Eastern Hemisphere, including Europe, Africa and western Asia. It should look something like a bright star moving across the sky.
Earth’s gravity will have a significant impact on Apophis – pushing and deforming the asteroid as one side is pulled more strongly toward our planet than the other. While Earth will not feel any impact, Apophis could experience some quakes and even landslides, ESA said.
Will Apophis hit Earth?
In short: No. At least not in our lifetime.
Although Apophis is classified as a near-Earth asteroid because its orbit brings it within 30 million miles of Earth, you have nothing to fear from it.
After its discovery in 2004, Apophis was initially considered one of the most dangerous asteroids to impact Earth, but that assessment has changed as astronomers tracked it and learned more about its orbit.
Although the risk of it impacting Earth rose to as high as 2.7% during its 2029 flyby, Apophis has since been removed from NASA’s Sentry Impact Risk Table. This is thanks to a radar observation campaign in March 2021 during a distant flyby that – combined with precise orbit analysis – allowed astronomers to determine that the asteroid poses no risk of impacting Earth for at least a century.
How big is the asteroid Apophis?
Apophis is nearly a quarter mile long—about the size of a cruise ship—and large enough to be visible to the naked eye as it passes Earth.
The Planetary Society compares its size to the equivalent of about five football fields and estimates that it is taller than the Empire State Building in New York City.
It’s hard to say exactly what Apophis looks like because scientists don’t yet have images of it. However, radar observations have shown that Apophis is roughly shaped like a peanut – a relatively common shape for near-Earth asteroids over 200 meters in diameter, according to NASA.
Apophis is thought to be made of stone and is composed of silicate (or rock) materials and a mixture of metallic nickel and iron.
What would happen if Apophis hit Earth?
Although Apophis is not as large and devastating as the asteroid that theoretically wiped out the dinosaurs 66 million years ago, it would cause widespread destruction within a radius of several hundred kilometers around its impact site.
The energy released would be equivalent to more than 1,000 megatons of TNT or dozens to hundreds of nuclear weapons, estimates the Planetary Society, a nonprofit organization promoting space research.
What does “Apophis” mean?
Apophis is no different from other asteroids in that it is a remnant from the early formation of our solar system about 4.6 billion years ago. It formed in the main asteroid belt between Mars and Jupiter and has been modified over millions of years by the gravitational influence of large planets like Jupiter, NASA said.
Now Apophis is coming frighteningly close to the Earth in its orbit around the sun.
Partly because of its proximity and the enormous destruction its impact on Earth would cause, astronomers named the asteroid after an ancient Egyptian god of disorder.
More specifically, Apophis is named after the demon serpent that embodied evil and chaos.
ESA and NASA want to explore Apophis
Space agencies and science institutes around the world plan to use this rare flyby to study Apophis from the ground using telescopes and even spacecraft.
NASA’s OSIRIS-REx, which collected and returned a sample from asteroid Bennu in September, has been renamed OSIRIS-APophis EXplorer (OSIRIS-APEX) and sent on a trajectory that would allow it to cross the asteroid’s orbit in 2029. When it rendezvous with Apophis in June of that year, OSIRIS-APEX will spend 18 months mapping the asteroid’s surface and analyzing its chemical composition, according to NASA.
Ground-based telescopes will also observe Apophis, but they won’t be able to see as much as the spacecraft as the asteroid approaches the sun, NASA said. Unlike the Bennu mission, however, OSIRIS-APEX will not collect a sample from Apophis.
The European Space Agency, NASA’s counterpart across the pond, is planning to launch its own spacecraft called Ramses.
The Ramses spacecraft, which must be ready for launch a year in advance, will meet Apophis before its flyby of Earth and accompany it as it moves out of our orbit. During this time, the mission will observe how the asteroid’s surface changes as it approaches Earth, the European Space Agency said in July.
NASA takes on dangerous asteroids
The expedition is part of the measures that NASA and other space agencies have taken in recent years to protect humanity from the threat posed by asteroids and other approaching space rocks such as comets.
In September 2022, NASA intentionally piloted a spacecraft at about 22,500 km/h toward the small asteroid Dimorphos.
Although Dimorphos posed no threat to Earth, the mission served as the first demonstration of NASA’s Double Asteroid Redirection Test (DART). If an approaching asteroid ever finds itself on a collision course with our planet, the DART method could prove crucial to deflecting and changing the object’s orbit, according to the space agency.
And to test whether authorities are prepared to protect Earth from space objects, NASA has conducted a series of exercises. The fifth and final of these took place in April, with the results announced in June. It was the first such exercise, involving about 100 international government officials to play out a hypothetical scenario of an approaching asteroid.
The exercise was organized by the U.S. space agency’s Planetary Defense Coordination Office, which was created in 2016 to catalog near-Earth objects that could crash into the planet.
NASA is also working on an asteroid-hunting telescope called NEO Surveyor to find near-Earth objects that can cause significant damage. The telescope is scheduled to launch in June 2028. It is designed to detect 90% of all asteroids and comets that are 460 feet (140 meters) or larger and come within 30 million miles (48 million kilometers) of Earth’s orbit.
Contributor: Claire Thornton, USA TODAY
Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at [email protected]
