At least we don't have to worry about asteroids wiping us out – not yet, anyway

An artist's illustration released by Nasa on Nov 4, 2021, showing the view from behind a probe just before it hits the Didymos binary system. The mission took place on Sept 26, 2022, but it will take a while to determine if the probe managed to knock the system's Dimorphos asteroid off course. — AFP/Nasa/Johns Hopkins Applied Physics Laboratory

There's a lot to worry about in the world right now: We seem to be teetering on the edge of a global recession and the nuclear threat is the most dangerous it’s been in decades. Not to mention the climate crisis and what that’s doing to our planet.

I don’t have any good news on any of that.

But remember the idea that Earth could be hit by an asteroid? We’ve made some progress there!

For those who have never opened a science book or watched a movie, an asteroid colliding with the Earth has long been thought of as one of the most probable ways our planet ends. In the past, collisions with asteroids have been the root cause of planet-level extinctions. And the statistics say it’s not a question of if but when Earth will be struck again.

To be fair, Earth is being hit by asteroids all the time. But those are smaller asteroids that the planet shrugs off like a rock star. Bigger asteroids hit Earth with less frequency. And that’s good because those are the devastating ones. Asteroids about 1km in diameter hit our planet every 500,000 years, while objects that are over 5km in diameter hit Earth every 10 million years.

And the last time our planet was hit by an asteroid over 10km in diameter was 66 million years ago – 66 million years ago, does that sound familiar? Yeah, because that was the time of the Cretaceous-Paleogene extinction event in which about 80% of all species of animals on the planet died. What caused it? You guessed it, that giant asteroid.

You might be thinking that these time frames sound huge so what are we worried about? And you might be right. The chances of Earth getting hit by one of these extinction-causing asteroids is pretty low. Especially if you think about them hitting Earth in the time frame of one’s lifetime. But, hey, odds are you won’t win the lottery either, and that happens to people every day, just not you. Or me. (Poor us.)

But back to dealing with that numerically improbable but still frightening threat of extinction due to asteroid: On Sept 26, 2022, Nasa (that’s the National Aeronautics and Space Administration in the United States) hit an asteroid with a probe to see if it could change its trajectory.

The target asteroid, Dimorphos, wasn’t headed toward Earth. In fact, it orbits another asteroid, Didymos, and both were minding their own cosmic business when Nasa decided to smash a probe into one of them – well, we have to test this on something. Nasa crashed a DART probe into Dimorphos. Dart stands for Double Asteroid Redirection Test. And the plan was pretty simple: If you run something into something else hard enough, that something you hit should change direction.

The space agency is pretty chuffed about the mission so far, with director of Planetary Science Dr Lori Glaze quoted in a BBC article as saying “We’re embarking on a new era of humankind, an era in which we potentially have the capability to protect ourselves from something like a dangerous hazardous asteroid impact. What an amazing thing; we’ve never had that capability before.”

And that’s true. Up to this point, Earth has been at the mercy of the cosmic fates, and we still are, but being able to slap an asteroid off its path of hitting our planet is a step in the right direction. OK, slap is a strong word, nudge is the word Nasa uses. But nudging your way to safety isn’t quite as dramatic.

So, how goes the asteroid nudging mission so far?

Well, a trail of debris thousands of kilometres long has been spotted and that is a direct impact of Nasa’s direct impact. So Dimorphos definitely felt the DART probe.

But has Dimorphos’ trajectory been altered?

The jury is still out on that.

Glaze said "potentially", remember – Nasa states it’s going to take a few weeks to see if Dimorphos’ path has shifted. And all the agency was aiming for was a slight shift in its orbit around Didymos anyway.

But in a world of increasing worry about economics and war and environmental devastation, we can at least stop worrying about getting hit by an asteroid. Not because we’ve got the technology to stop an asteroid from hitting us – clearly we’re a few steps away from that – but mostly because the frequency with which Earth gets hit by large asteroids spans hundred of thousands if not millions of years. Let’s just hope we don’t mess up our planet on our own before an asteroid has a chance to do it.

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Big Smile, No Teeth columnist Jason Godfrey – a model who once was told to give the camera a ‘big smile, no teeth’ – has worked internationally for two decades in fashion and continues to work in dramas, documentaries, and lifestyle programming. Write to him at [e-mail] and follow him on instagram.com/bigsmilenoteeth and facebook.com/bigsmilenoteeth. The views expressed here are entirely the writer's own.