The Apocalypse Barely Missed Us 115 Years Ago, But It Could Happen Any Moment

It’s Asteroid Day, which is one of the rare days on the calendar meant to serve largely as a warning.

On June 30, 1908—115 years ago today—there was a remarkable boom, bright lights in the sky and in an instant, an area the size of today’s Tokyo (or more than double the area of New York City) was leveled.

Fortunately, the area was in remote Siberia above the Tunguska River, and nearly all of the damage was done to trees. Asteroid Day is an occasion to consider what might happen if the next such incident struck a more densely populated locale instead, which could happen without warning any time.

The lack of many eyewitnesses to the “Tunguska Event” meant it took decades to determine what had actually happened, which is that a meteoroid had entered our atmosphere at high velocity and probably exploded in the sky over Russia, generating a powerful airburst decimating everything in an 800-square-mile area.

The offending space rock arrived without any warning and provided no time to prepare, respond or even brace for impact. A century later, history repeated itself when a similar bolide blazed a path across the sky, again over Russia, in 2013. There was a similar airburst that blew out thousands of windows and damaged buildings in the city of Chelyabinsk.

Again, there was no warning, despite the existence in this century of multiple sky surveys that watch for such threats from the near cosmos. (The Chelyabinsk bolide came from the direction of the sun, a notable blind spot in our surveys that an upcoming NASA mission aims to address).

In recent years, research into the two events, considered to be the most significant meteor impacts in modern times, found we got quite lucky in both cases. Analysis suggests that the Tunguska meteoroid may not have been much bigger than the one over Chelyabinsk, but approached the surface at a much steeper angle, which led to more widespread damage.

There were hundreds of minor injuries, but no one was killed at Chelyabinsk. It’s thought that three deaths may have been linked to the Tunguska airburst, likely from falling trees and a heart attack.

It appears we were fortunate that the more powerful blast of the two occurred over one of the least populated areas on Earth, while the blast that did target a city of one million residents was tame by comparison.

The Unlucky Scenario

What if we hadn’t been so lucky? What about the worst-case scenario in which a Tunguska-like blast happens over a densely populated area like Tokyo or New York? The few thousand miles that separate these locations from Russia is nothing compared to the millions of miles many asteroids travel in a year.

Imagine the airburst that decimates much of the New York City metropolis without warning instead of Siberian taiga. You might say it’s hyperbole to suggest such an event would trigger an apocalypse, with the damage being limited to a single geographic region.

But history is littered with fallen dominoes. The distance between German tanks rolling into Poland and humanity opening the Pandora’s Box of atomic weapons a continent away was less than a decade, and that was in an era where things moved much, much slower than today.

We’re still dealing with the geopolitical reordering that was initiated mere weeks after September 11, 2011 and society hasn’t exactly snapped back to where it was before March 2020 either.

Saving The Planet

So, as many Californians have been asking themselves for decades, we should all be wondering—what will happen when the big one comes? Be it a meteor, an earthquake or a solar flare? Yes, you can add an erupting supervolcano, too, if you’d like.

All of these are likely coming. I would argue that the meteor version of this disaster movie is the most concerning, given the track record. Two near misses in roughly a century and that notorious direct hit that took out the dinosaurs is plenty of reason to worry.

So on this Asteroid Day, it’s worth taking a minute to consider the things that are out of our control, that threaten our existence and which can’t be solved by free markets.

The phrase of art is planetary protection, and it requires more science, telescopes and engineers. NASA’s recent DART mission to redirect an asteroid was a key step to making us all safer, and others like NEO Surveyor will continue the process.

We just have to hope the big one doesn’t come while we’re still learning to defend ourselves.