Brussels (Brussels Morning Newspaper) – NASA has assigned the asteroid named “2024 YR4” an impact probability of 3.1% for the year 2032 – the highest risk level ever recorded for a near-Earth object. Heads up, it’s a “city killer”.
Highest risk ever assigned to an asteroid
For the first time in recorded history, The National Aeronautics and Space Administration (NASA) has assigned an asteroid a 3.1% chance of hitting earth, a percentage that has been rising for the past few days as it was sitting at 2.3% on February the 7th. The asteroid named “2024 YR4”, a relatively small but significant space rock, would be on course to hit Earth on the 22nd of 2032 – that’s a 1-in-32 chance. This level of uncertainty is unprecedented, and while most space threats are judged null as more data refines calculations, this particular asteroid has forced scientists to confront a disturbing reality: there is a real chance we are getting hit.
Danny Steeghs, head of the Astronomy and Astrophysics Group at the University of Warwick, attempted to put the risk into perspective, stating:
“Once every five years, you might have something like this, but mostly the threats disappear. Actual impact events are one every hundreds of years”
The last truly devastating asteroid impact on Earth was 66 million years ago, when a 10-kilometer-wide asteroid wiped out the dinosaurs and a few scientists have been vocal about the fact they believe it is not a matter of if but when another impact occurs. The fact that “2024 YR4” has been flagged with such a high probability should serve as a reminder that humanity is still at the mercy of space.
With less than eight years until its potential impact, global space agencies are already putting efforts to track, analyze, and – if necessary – prepare for the asteroid.
Is there a real danger to humanity?
There is no danger to humanity as a whole, but there is a danger to humans. With an estimated diameter between 40 and 100 meters, this asteroid falls into the category of a “city killer” – large enough to flatten an entire city upon impact. Historically, asteroids of this size have only struck Earth once every few thousand years, but probability and history are of little comfort when facing a 1-in-32 roll of the cosmic dice.
If “2024 YR4” hits Earth, it would strike at 17 kilometers per second, unleashing an energy equivalent to 8 megatons of TNT – that’s 533 times the power of the Hiroshima bomb used by the American in World War II. It’s important to keep in mind that this level of energy is still not enough to cause a civilization threatening catastrophe.
Humanity has new tools to play with
On a brighter note, humanity is no longer as defenseless against cosmic threats as they have been throughout their existence. Several deflection strategies are already under consideration by NASA and the European Space Agency, and there are some concrete options. One leading option for instance is kinetic impact, a technique inspired by NASA’s DART mission, which envision a potential spacecraft that would crash on the asteroid and significantly alter its trajectory.
The Space Mission Planning Advisory Group (SMPAG), a coalition dedicated to planetary defense, is set to reconvene in late April or early May 2025 to reassess the situation. If the threat is judged as necessary of a response, they will recommend concrete actions – potentially marking the first real-world test of asteroid deflection on such as threatening scale.
