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Asteroid Apophis, which poses a potential threat to the Earth, will approach our planet in April 2029 at a record distance - only 32 thousand kilometers. This is closer than some artificial satellites. Due to the gravitational influence of the Earth, its surface undergoes serious changes, including earthquakes and landslides. Such data were presented in a new study on arXiv site.
The approach of the Apophis asteroid to Earth in April 2029, although it will be quite close, will not cause a direct physical impact on our planet. However, there are several aspects that may be of interest. According to NASA, probability of collision with Earth in 2029 absent, since its trajectory does not cross the Earth's orbit. Detailed observations made it possible to completely exclude the risk of a collision during this approach. The Earth's gravitational field itself can significantly change the surface and rotation of Apophis.
Open source photos
How will convergence with Earth affect Apophis?
Apophis has a diameter of about 340 meters and a shape similar to a peanut. After its discovery in 2004, scientists initially thought it might collide with Earth. However, the refined data of 2021 made it possible to exclude this possibility. To predict possible changes on the asteroid's surface, an international team of scientists conducted simulations using information about the Itokawa asteroid, which has similar physical characteristics.
As a result of the study, two main processes that can take place on the surface of Apophis under the influence of Earth's gravity were revealed:
1. Seismic tremors. An hour before maximum approach, and for some time after, our planet's gravity will cause oscillations inside the asteroid. Although these tremors will not be significant by Earth standards, due to the weak gravity of Apophis, even small fluctuations can cause changes on its surface. In particular, it can cause the ejection of small rocks into space, although a large part of the debris will return again, leaving traces on the surface.
2. Changing the rotation speed. The Earth's gravitational field can slightly change the speed and rotation pattern of the asteroid, which will lead to a gradual destabilization of the tilted rocks on the surface. These landslides can last tens of thousands of years, changing the surface structure of Apophis for a long time.
NASA plans to test the results of the study with the OSIRIS-APEX mission, which will meet with Apophis in 2029. The spacecraft will spend 18 months studying its chemical composition and documenting all the changes on the surface after the record approach to Earth.
Open source photos
The approach of Apophis is a great opportunity to test existing asteroid observation systems and improve methods for predicting their trajectories. This rapprochement will allow to test readiness for monitoring objects that may be potentially dangerous in the future.
Other dangerous near-Earth asteroids
• Terrestrial observatories have already discovered more than 30 near-Earth objects, of which approximately 1 are classified as potentially dangerous.
• An asteroid the size of a car in 2020 flew at a distance of only 2950 kilometers from the Earth. The planet's gravity changed its orbit.
• The second Trojan asteroid in Earth orbit confirmed in 2021. This celestial body shares an orbit with our planet for about 500 years.
