If any of these asteroids were heading our way, hell would probably break loose. A tabletop exercise (see PDF below for more information) conducted by NASA in May showed that at present there is nothing humanity can do to stop an asteroid from hitting Europe, for example, not even with six months of prior warning.
During the exercise, several defense scenarios were tested. The first was deflection, that is, hitting the incoming asteroid with something hard and fast enough to change its course. This was ruled out because, well, six months of warning and our current level of technology was not enough to significantly change the course of the simulated rock.
Then NASA envisioned how it would launch nuclear warheads at the thing, but got stuck in calculating how much force it would take to wipe out the asteroid. Because it was impossible to determine the make-up of the asteroid, it was impossible to determine the size of a nuclear bomb to send. The largest available was considered, but even that was deemed unnecessary for asteroids over ~ 100m to ~ 210m, and with densities ranging from 5g / cm3 to 1g / cm3.
What is more concerning is that with our current technological level, six months would not be enough to launch a mission to study the rock more closely, making all other efforts largely unnecessary.
Now NASA knows an asteroid impact is a matter of when, not if. And he’s planning to do something, at least to make us feel like we still have a chance to fight.
As of 2018, a number of agency branches have been working on something called DART. It’s short for Double Asteroid Redirection Test, and it’s essentially a suicidal spaceship sent into the void to prove if all that fancy talk about the deviation in movies, literature, and tabletop exercises is worth anything.
DART is expected to take off on top of a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in November. It will be heading into space, heading for a binary asteroid called Didymos, and plans to crash into the thing in the fall of 2022 at a speed of 15,000 mph (24,140 km / h), to see s’ it can change its trajectory.
DART is a very small thing, measuring 12.5 meters × 2.4 meters (41.0 feet × 7.9 feet). It includes a motor called NEXT to move around, Roll-Out Solar Arrays (ROSA) to give it energy, two batteries to store this energy, a star tracker to find your way around, and the Didymos Reconnaissance and Asteroid Camera for Optical ( DRACO) to record the moment of impact.
That’s it. No fancy lasers, no nuclear warheads, no humans on board. Just a small piece of metal and other material, thrown from a planet that Didymos probably doesn’t even know existed, and meant to prove a point.
Didymos’ main body measures 780 meters (2,560 feet) in diameter, while the smaller, orbiting, is only 160 meters (525 feet) in diameter, and DART is not expected to have such a big impact on the pair. of rocks floating in space.
It’s the smallest asteroid that DART is aiming for, and the goal it has set for itself may seem rather small: to change the speed and orbit of the asteroid around the main body by a fraction of one percent. . This does, however, translate into a change in the orbital period of several minutes – enough to be seen from Earth using telescopes and to prove that yes, humans could possibly deflect asteroids. Provided, of course, that we mature the technology quickly enough and another asteroid doesn’t hit us in the meantime.
While this is the first dedicated mission to see if deflection can be a thing, DART won’t be the first time humans have abused an asteroid. In 2019, the Japanese Space Agency (JAXA) fired a projectile called the Small Carry-on Impactor (SCI) from the Hayabusa2 spacecraft, directly at the surface of the asteroid Ryugu.
The slug hit the surface at a speed of 2 km per second (4,473 mph), causing a crater 2 meters in diameter (6.5 feet). Additionally, rocks on the surface were disturbed within 30 meters (98 feet) of the center of the impact crater, according to Kobe University.
This means that there is no reason for DART not to work. It only remains to see how quickly this can lead to something really useful for self-defense.