Asteroid 2024 YR4: Cataclysm in the offing?

Astronomers recently discovered a 60-meter-diameter asteroid that will cross Earth's orbit on December 22, 2032. It's been dubbed 2024 YR4, and while NASA calls it a "potentially hazardous object," it also says the probability of impact is 3.1%, but now it's only 0.005%.

Okay, 0.005% isn't much... But it's not zero! Imagine an object like 2024 YR4, the size of a 20-story building, hitting Earth at 50,000 km/h. The energy released would be about 8 megatons of TNT, equivalent to 500 Hiroshima bombs. Get it? 500 nuclear bombs exploding all at once in the same spot.

Impact over Barcelona. What would it be like?

I know the chances are minimal, but let's imagine that in 2024 YR4 falls on Barcelona, right in the middle of Plaça Catalunya, for example. It would be apocalyptic! The initial impact alone would reduce all the buildings and monuments in the Eixample district to rubble, leaving a crater 5 or 6 km in diameter.

But that wouldn't be all: the immense amount of material thrown into the air by the force of the initial impact would trigger a shower of incandescent rocks, like a massive firestorm, which would set fire to and destroy an area of about 30 kilometers in all directions.

Not only would Barcelona be burned to the ground, but also Badalona, Masnou, Premià, Mataró, Cerdanyola, Mollet, Sant Cugat, Hospitalet... Anyway, I'll stop! The result would be millions of deaths and a completely devastated country. It would probably take generations to recover. But don't worry: the probability of it colliding with Earth is only 0.005%, and much lower for it to fall right on Barcelona.

Should we fear asteroids?

Of course. As Neil de Grasse Tyson, the famous astrophysicist and science communicator, says: "The dinosaurs didn't have a space program, and that's why they're no longer here to talk about asteroids. But we are there, and we do have the power to do something. I don't want to be the shame of the galaxy, having the ability to deflect one or all of them. If this happened, we'd be the laughingstock of the aliens of the cosmos.".

And since we don't want to be the laughingstock of the aliens of the cosmos, we're already working on it. Asteroids and other things that pass close to Earth are called NEOs (near-Earth objects, I mean, near-Earth objects) and a network of telescopes from NASA and other agencies around the world is constantly working to detect and track them.

So far, more than 36,000 NEOs have been discovered, 950 of which are one kilometer or larger in diameter. The most worrying are the 2,418 classified as PHAs (potentially hazardous asteroids), that is, if these asteroids were to collide with us, we would take a lot of damage. It is believed that we could deflect them by crashing a heavy aircraft into a specific point on their surface. NASA, with the DART mission, recently demonstrated that this is possible.

Now, to act, it takes time. If we knew that in 20 or 30 years a large asteroid would collide with the Earth, governments would allocate all the necessary resources to avoid it. And if we couldn't avoid it, at least we would have time to evacuate the impact zone, prepare shelters and stockpile resources to survive the post-disaster.

As Carolyn Shoemaker, astronomer and discoverer of quotes, says: "Every asteroid we find is one less threat. Patience and observation are our best weapons." Come on!