Incoming Asteroid just might hit earth

Katrina Borthwick - 3 February 2025

It’s not a good day when a closer analysis of the path of a near-earth approaching asteroid doesn’t rule out impact, but instead shows that it might actually hit earth in 2032.

This asteroid, named YR24, is around 40 to 100 metres in size. It was observed on December 27th by ATLAS (the Asteroid Terrestrial Last Alert System) after its closest approach to earth two days earlier, when it was about 800,000 km out. NASA was asked to check whether it would come back and hit earth in the future, and its trajectory projection was also updated on 27 January.

Unfortunately, that projection came out worse, and says the asteroid has a 1.6% chance of hitting earth on 22 December 2032 - ranking it a 3 out of 10 on the Torino scale - a scale that ranks the danger to earth. The ESA (European Space Agency) confirmed this two days later.

This is not a doomsday asteroid by any means, but it would cause a horrific amount of damage if it hits earth. The impact would be equivalent to a 10 megaton bomb. As it is a rocky asteroid, rather than metallic, it is expected it would detonate in the atmosphere like the Tunguska river event that occurred in Siberia, Russia in 1908.

In the Tunguska event, people far away observed a light as bright as the sun moving across the sky, then observed light from the blast from the detonation. The shockwave registered on seismic stations across Europe, and even as far out as Washington D.C.. 2,150 square kilometres of trees were flattened. Fortunately, due to its remote location, it’s estimated only 3 people died. This was a 50-60 metre asteroid or comet that exploded 5-10 km high, with a force of anywhere between 3 and 50 megatons. Such an explosion is quite capable of taking out a city, even if it doesn’t hit the ground. If it hits the water, it could cause a tsunami.

YR24 could be a similar size to the Tunguska event, or it may be up to twice as big. So it could be more devastating, and of course may land somewhere with more people.

An amateur astronomer in Germany, Daniel Bamberger, has calculated the possible impact corridor. See the map below. New Zealand isn’t on the corridor at this stage, but bear in mind that this will be updated as we get more information, and our island nation is also vulnerable to tsunamis, so a direct hit isn’t needed for an impact to affect us.

The calculations and the Torino risk will be updated on an ongoing basis, but we probably won’t know for sure if it will hit until 2028, when it next flies by the Earth. As of the time of writing, preparations for a mission response should an impact be found to be imminent were due to start this week. This would likely take the same approach as a successful asteroid redirection%20asteroid%20called%20Didymos.) test that occurred in 2022, smashing something heavy into it so it changes direction. If that won’t work, then we would be looking at evacuation of the predicted impact region. Serious stuff.

These sorts of asteroids go by Earth quite often, and most of them don’t bother us. But they do definitely happen on a smaller scale, and they might be somewhat underreported where they aren’t hitting major western cities. For example, there was a detonation of a 20 metre wide asteroid over Chelyabinsk, Russia in 2013. It shattered windows and injured hundreds of people.

1.6% doesn’t sound very high, and it’s not a planet killer, but it is definitely not nothing. The chances of this one hitting the Earth is 16 times higher than your chance of dying in a motor vehicle accident in any one year in New Zealand. So this is definitely not something to dismiss if you are told to move out of the way of this one.

On a final, lighter note, I am guessing this asteroid will get a fancy new name, as YR24 doesn’t really seem dramatic enough. Many asteroids are named after famous people, but then there’s “88705 Potato” and “95962 Copito” - which is a specific Spanish albino gorilla. Although we’re also bound to hear some people claiming this new object is some sort of alien space missile. But that sounds a bit too Starship Troopers for me.