What Would Happen If A ‘City-Killer’ Asteroid Hits London? Scientists Discuss Grim Scenario

Astrophysicist Neil deGrasse Tyson and cosmochemist Natalie Starkey recently discussed what would happen if the asteroid that caused the Chelyabinsk impact event hit a heavily-populated city instead.

In 2013, the Chelyabinsk Oblast region in Russia was rocked after a 20-meter-long meteor breached the Earth’s atmosphere and detonated mid-air. The explosion had a blast yield equivalent to 500 kilotons of TNT, which is 33 times more powerful than the atomic bomb dropped at Hiroshima, Japan in World War II. Fortunately, the bulk of the explosion was absorbed by Earth’s atmosphere.

The airburst damaged over 7,000 structures within the surrounding area. Although the incident caused a large number of injuries, no fatalities were reported.

Aside from exploding mid-air, another factor that prevented casualties during the incident was Chelyabinsk Oblast’s population. Compared to other major cities, this Russian region has a relatively small population.

Recently, Tyson and Starkey talked about the Chelyabinsk meteor event and what would happen if it occurred in a populated area such as London. The two scientists discussed the dark scenario during a previous “Cosmic Queries – Asteroids and Comets” episode of Tyson’s StarTalk podcast.

“It was fairly large, I guess kind of like a double-decker bus, and that didn’t actually kill anybody but it caused quite a lot of damage in the region and it had this big sonic boom as it came through the atmosphere,” Starkey said about the Chelyabinsk meteor event.

According to Starkey, if the same meteor hit London and actually collided with the ground, it would have been a major issue. This will be primarily due to the sheer volume of casualties, property damage and even fatalities that it will cause. Given the asteroid’s size, it has the potential of wiping out an entire city.

“That would be quite an issue if that had landed in the center of London, so it’s sort of lucky that most of the planet is empty and a lot of these asteroids tend to land in the ocean so we don’t see them and they don’t cause any harm,” she explained.

Even if an asteroid misses an entire city or state and lands in the ocean instead, it could still cause a lot of damage. As discussed by Tyson and Starkey in the same episode, a massive asteroid hitting the ocean could trigger a series of mega-tsunamis that can wipe out populated regions.