According to calculations, the asteroid Apophis should strike Earth in 2029. The risk has been eliminated - but the asteroid comes very close.
- The asteroid (99942) Apophis was named after the god of chaos in Egyptian mythology
- After his discovery, there was a chance that he would hit Earth in 2029
- It is now known that a collision between Apophis and the earth is ruled out for the time being
His name does not bode well: Apophis, god of chaos . This is the name of the asteroid (99942) Apophis , which was discovered by astronomers at the Kitt Peak National Observatory in Arizona in June 2004. In Egyptian mythology, Apophis is the god of chaos and darkness. And for a short time, there was a real fear that asteroid Apophis could cause chaos on Earth: after its discovery, it was calculated that the asteroid was 2.7 percent more likely to collide with Earth in 2029.
But the concern was unfounded: shortly after the calculation, Asteroid Apophis was discovered on older images and the path was more precisely calculated. It turned out that a collision with the earth in 2029 is impossible, in the subsequent period an impact on the earth in 2036 was also excluded.
Asteroid Apophis does not hit Earth - but there was a danger
Apophis is approximately 370 meters in diameter, an impact of the asteroid on Earth would have released an energy of around 900 megatons - 18 times the largest man-made nuclear explosion. The impact this would have on Earth depends heavily on where and at what angle the celestial body strikes.
What is certain is that an asteroid of this size would cause regional damage if struck - a so-called "global killer" like the asteroid, which was responsible 66 years ago * for the dinosaurs becoming extinct *, would have to have a significantly higher impact energy.
Apophis was the asteroid with the (briefly) greatest risk of impact
To this day, Apophis is considered the asteroid for which (at least for a short time) the greatest risk of impact was calculated. On the Turin scale, which ranges from 0 (no danger) to 10 (safe collision that threatens civilization), Apophis was briefly rated 4 (closer approximation, which requires the attention of astronomers). In the meantime, Asteroid Apophis is rated 0 again.
Although the risk of impact has long been averted, asteroid researchers are eagerly waiting for April 13, 2029 . This is the day that Apophis comes very close to Earth. The asteroid will then approach the earth's surface at a speed of around 25,000 kilometers per hour. This is closer than the orbit of geostationary satellites, such as telecommunications satellites, which are located at an altitude of approximately 36,000 kilometers above the earth. Apophis, however, poses no threat to the satellites because it does not intersect the geostationary orbit.
How Asteroid Apophis Approaches Earth
Asteroid Apophis flies past Earth - rare event
That a large asteroid * like Apophis flies so close to Earth is a rare event and a good opportunity that astronomers want to take. "We will observe the asteroid with optical and radar telescopes," said NASA scientist Marina Brozovic in a message. “With radar observation, we might even be able to see surface details that are only a few meters tall.”
The asteroid * is so large and comes so close to Earth that it will even be visible to the naked eye. At the time of its closest approach to Earth, it will travel across the Atlantic - tracked by numerous telescopes.
The path of asteroid Apophis in April 2029
Encounter with Earth will change course of Asteroid Apophis
"We know that close contact with Earth will change the course of Asteroid Apophis ," explains astronomer Davide Farnocchia from the Center for Research on Near-Earth Objects (CNEOS). It is even possible that the approach also changes how the asteroid rotates. "It is also possible that there are some changes on the surface, such as small avalanches," says Farnocchia.
Research currently knows more than 2,000 potentially dangerous asteroids. "Observing Apophis during its 2029 flyby gives us important scientific knowledge that could one day be used for planetary defense," said Paul Chodas, director of CNEOS.
Can you distract an asteroid that threatens Earth? Esa and Nasa want to test the defense against an asteroid with the "AIDA" mission *. Researchers hope that artificial intelligence can help identify potential dangerous asteroids in the future.
By Tanja Banner
* fr.de is part of the nationwide Ippen-Digital central editorial office.
Rubric list image: © NASA / JPL-Caltech