Astronomers have identified a new asteroid, 2024 YR4, whose trajectory gives it a 3,1% chance of colliding with Earth on December 22, 2032. A low risk but the highest ever recorded since monitoring of celestial objects began.
The asteroid, estimated to be between 40 and 90 metres in diameter, could cause major destruction if it were to crash into Earth. Its impact would be 500 times more powerful than the Hiroshima bomb, enough to wipe out an entire city or trigger a tsunami if it fell close to the coast.
However, experts are warning about the prediction. "I'm not panicking," says Bruce Betts of the Planetary Society, stressing that the data are preliminary and will evolve with further observations.
The previous record for impact risk was held by the asteroid Apophis, which briefly showed a 2,7% chance of collision in 2029. But more precise analyses quickly ruled out any danger.
Scientists are now counting on the James Webb Space Telescope, which will observe 2024 YR4 in March, to refine its characteristics and trajectory. The challenge is considerable: the asteroid is gradually moving away from Earth and will not become visible again until 2028.
If the risk of collision remains high in the coming years, the scientific community could consider a deflection mission. In 2022, NASA demonstrated that this type of intervention was possible by changing the trajectory of a harmless asteroid through a controlled impact.
For the moment, no worst-case scenario is to be expected, but monitoring continues, because even a very rare event can have considerable consequences.
