NASA space boffins hit an asteroid seven million miles from Earth last night at 15,000mph
What with the war in Ukraine, the spiraling cost of living crisis, and petty disagreements already bubbling on Strictly, there’s quite enough to worry about right now.
But as we all know, if it’s not one thing it’s another, and so now we’re suddenly awash with asteroid disaster stories.
An asteroid — crashing into Earth? Forget the economy. We’d be obliterated. Up in smoke. Lost forever with the poor old dinosaurs. We’ve all seen the end-of-the-world disaster movies. Even a smallish asteroid can wipe out an entire country.
Which is why at precisely 12.14am this morning, as most of us were tucked up in bed, an extraordinary drama was unfolding seven million miles away in space. The world’s first planetary defense test mission. An extraordinary galactic space battle.
On one side was the Double Asteroid Redirection Test, or Dart — a £300 million probe that is 19m (62ft) long and weighs half a tonne.
On the other was Dimorphos. A bulky asteroid (a mass of space rock, as opposed to a comet, which is a mixture of ice, rock and gas), it measures 163m (530ft) across and is currently orbiting a far bigger asteroid, Didymos (780m or 2,560ft) ), once every 11 hours and 55 minutes.
The big moment — the culmination of an epic mission starting last November when it took off atop a SpaceX Falcon 9 rocket from an air force base in California — was scheduled for just after midnight.
The Dart — piloted for the last part of its journey by software and thrusters, and fueled by large solar panels — would smash into its target, almost head-on, at approximately 15,000 miles per hour.
The impact would destroy the probe completely, and, fingers crossed, nudge Dimorphos off course sufficiently to tighten its orbit around Didymos to once every 11 hours and 45 minutes.
In the meantime, a LICIACube — a specialist Italian camera released some days ago from the probe — would record the moment of ‘deep impact’ from 31 miles back and beam the images back to Earth. At least that was the plan.
Or, as Professor Alan Fitzsimmons, an astronomer and member of the Nasa Dart investigation team at Queen’s University Belfast, has put it: ‘It’s a very complicated game of cosmic billiards. What we want to do is use as much energy [as we can] from Dart to move the asteroid.’
When you read this, it will either have worked, and Dimorphos will have been redirected, its course changed for ever, and the Dart rendered to dust.
Or it won’t. The Dart will be goodness knows where and the Dimorphos will be swirling happily in its original orbit.
NASA’s DART successfully impacted the Dimorphos asteroid on Monday at 7:14pm ET. This is the first planetary defense test and it could be used to save Earth
But before you start panicking, clutching your loved ones and channelling your best Bruce Willis in the 1998 asteroid disaster movie Armageddon, take a breath.
Because Dimorphos was one big lump of rock that was never going to hit Earth. Nowhere near. It never posed us any danger at all. This was all just a very expensive experiment to see whether devastating asteroids can be nudged off course if they’re heading straight for us. But a very important experiment.
There are plenty of asteroids that could hit us, which means that experts generally talk in terms of when, rather than if.
Indeed, while scientists have identified more than 95 per cent of the monsters that would wipe us all out, there are still a lot of smaller ones roaring about — barely a third of the 28,000 asteroids with a diameter of at least 140m (460ft) have been spotted.
(It doesn’t help that the smaller the asteroid is, the more dimly it shines and the harder it is to spot until it’s closer to Earth.)
Even the smallest of those are probably big enough to knock out Belgium, Wales or London. And the relatively small Dimorphos could easily create a crater over a mile wide, 200m (650ft) deep and cause intense damage for miles.
All of which sounds rather grim.
However, unlike earthquakes, volcanic eruptions and tsunamis, the upside here is that we get plenty of advance notice of the asteroids hurtling towards us at 20 miles a second.
Thanks to the epic distances they travel, we have years, decades, or centuries even, of notice of an impending strike.
‘Hollywood and movies, they have to make it exciting,’ explained Dr Lindley Johnson, NASA’s planetary defense officer, last week. ‘You know, they find the asteroid only 18 days before it’s going to impact and everybody runs around as if they’re on fire.’
Not that there hasn’t been plenty of real-life drama on the asteroid front. It was back in the 1980s when scientists realised that an asteroid had been responsible for the 112-mile-wide Chicxulub crater of Mexico’s Yucatan Peninsula, which killed off all non-avian dinosaurs.
And over the millennia, we’ve been properly battered by flying debris, with nearly 200 impact craters discovered around the world as evidence.
The Tunguska Event of 1908 was the last time Earth was hit by a big meteor — 76m (250ft) across.