On September 24, 2182, asteroid Bennu could collide with Earth. Although the chance is small – only 0.037% (equivalent to a 1 in 2700 chance), Bennu remains one of the most dangerous asteroids in the Solar System. Scientists from South Korea have modeled the consequences of such a collision, which include global cooling and planetary-scale famine.
Possible consequences of collision
According to a study published in the journal Science Advances, a medium-sized asteroid colliding with Earth would have catastrophic consequences for the climate. Emitting hundreds of millions of tons of dust into the atmosphere would cover the Sun and reduce the heating of the Earth’s surface. This would result in a 4°C decrease in temperature, a 15% decrease in precipitation, and about 32% depletion of the ozone layer. Such changes would negatively impact plant photosynthesis, reducing its efficiency by 20-30%, causing widespread disruption to food chains across the planet.
Despite the significant risks, the researchers note that the dust could help ocean plankton grow. Plankton recover much faster than land plants – in six months versus two to three years. This could be a key factor in partial ecosystem recovery.
Features of Bennu
Bennu is a near-Earth asteroid about 500 meters in diameter that passes close to Earth every six years. It formed about 700 million to 2 billion years ago, breaking off from larger asteroids. NASA’s OSIRIS-REx mission in 2020 sampled Bennu and brought it back to Earth, allowing its composition to be studied. In particular, the asteroid contains organic matter – the building blocks of life.
Threat to humanity
Compared to the Chicxulub asteroid that caused the extinction of the dinosaurs 66 million years ago, Bennu is much smaller. Chicxulub had a diameter of about 10 km, while Bennu was only 0.5 km. However, medium-sized asteroids like Bennu fall to our planet more often – approximately every 100,000 to 200,000 years. According to Axel Timmermann, director of the IBS Center for Climate Physics, such events may have influenced human evolution.
Humanity has already taken important steps to protect the planet from space threats. In 2022, NASA’s DART mission successfully altered the asteroid’s trajectory with a kinetic collision, proving that a potential threat to Earth could be averted. This opens up prospects for further innovations in collision avoidance.
Although a collision with Bennu is unlikely, astronomers have already detected asteroid 2024 YR4, which has a high probability of colliding with Earth at 1.9% in 2032.
Earlier we explained the interesting features of the asteroid Bennu.
According to CNN
