- Space agencies around the world took part in a NASA simulation of an asteroid-impact scenario.
- The participating experts learned about a fictitious asteroid’s trajectory and had to react.
- In the exercise, they couldn’t stop it from hitting Europe, showing how unprepared we are for such a crisis.
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Scientists around the world have been bamboozled this week by a fictitious asteroid heading toward Earth.
A group of experts from US and European space agencies attended a week-long exercise led by NASA in which they faced a hypothetical scenario: An asteroid 35 million miles away was approaching the planet and could hit within six months.
With each passing day of the exercise, the participants learned more about the asteroid’s size, trajectory, and chance of impact. Then they had to cooperate and use their technological knowledge to see if anything could be done to stop the space rock.
The experts fell short. The group determined that none of Earth’s existing technologies could stop the hypothetical asteroid from striking given the six-month timeframe of the simulation. In this alternate reality, the asteroid crashed into eastern Europe.
As far as we know, no asteroids currently pose a threat to Earth in this way. But an estimated two-thirds of asteroids 460 feet in size or bigger – large enough to wreak considerable havoc – remain undiscovered. That’s why NASA and other agencies are attempting to prepare for such a situation.
“These exercises ultimately help the planetary-defense community communicate with each other and with our governments to ensure we are all coordinated should a potential impact threat be identified in the future,” Lindley Johnson, NASA’s planetary defense officer, said in a press release.
6 months is not enough time to prepare for an asteroid impact
The fictitious asteroid in the simulation was called 2021PDC. In NASA’s scenario, it was first “spotted” on April 19, and after a week scientists were able to calculate that it had a 5% of hitting our planet on October 20, six months after its discovery date.
But they concluded that such missions wouldn’t be able to get off the ground in the short amount of time before the asteroid’s impact.
“If confronted with the 2021PDC hypothetical scenario in real life, we would not be able us to launch any spacecraft on such short notice with current capabilities,” the participants said.
They also considered trying to blow up or disrupt the asteroid using a nuclear explosive device.
“Deploying a nuclear disruption mission could significantly reduce the risk of impact damage,” they found.
Still, the simulation stipulated that 2021PDC could be anywhere from 114 feet to half a mile in size, so the chance that a nuke could make a dent was uncertain.
Day 3 of the exercise skipped ahead to June 30, and Earth’s future looked grim: 2021PDC’s impact trajectory showed it headed for eastern Europe. By Day 4, which fast-forwarded to a week before the asteroid impact, there was a 99% chance the asteroid would hit near the border between Germany, the Czech Republic, and Austria. The explosion would bring as much energy as a large nuclear bomb.
All that could be done was evacuate the affected regions ahead of time.
It’s tempting to assume that in the real world, astronomers would spot an asteroid akin to 2021PDC with much more notice than six months. But the world’s ability to surveil near-Earth objects (NEOs) is woefully incomplete.
Any space rock with an orbit that takes it within 125 million miles of the sun is considered an NEO. But Johnson said in July that NASA thinks “we’ve only found about a third of the population of asteroids that are out there that could represent an impact hazard to the Earth.”
Of course, humanity hopes to avoid a surprise like the dinosaurs got 65 million years ago, when a 6-mile-wide asteroid crashed into the Earth. But in recent years, scientists have missed plenty of large, dangerous objects that came close.