ESAScience Office An illustration of the plume and crater left by NASA's dart probe after crashing into an asteroid a test of technologies intended to help us deflect asteroids in the future.

In 2022, NASA plans to send a probe crashing into an asteroid at more than 13,000 miles per hour to deflect it off its course.

This particular asteroid isn't a threat to us. But NASA is trying to figure out how it might defend Earth from asteroids more generally in case a big one really does head our way in the future.

This is all part of a joint mission NASA's planning with the European Space Agency called Asteroid Impact & Deflection Assessment (AIDA). It will start with the launch of a European craft in 2020 to study and map the asteroid first. ESA entered the preliminary design phase of that initial reconnaissance mission earlier this week.

The goal is to develop the technology and expertise that might be necessary to nudge an asteroid out of its orbit if we ever discovered one heading for Earth. It might sound far-fetched, but the truth is that asteroids are a potentially serious threat and foresighted missions like this could theoretically be the difference between a closely averted disaster and catastrophe.

1. The plan to crash into an asteroid

In 2020, the European Space Agency plans to launch its Asteroid Impact Mission, or AIM probe. It'll travel to an asteroid named Didymos, which is orbited by a relatively small (about 550 feet wide) asteroid called Didymoon.

Over the course of a year or so, AIM will orbit Didymoon, mapping its surface and collecting data on its mass and overall structure. Current plans also call for it to send out a pair of smaller satellites to collect more data, as well as a lander that would touch down on Didymoon itself becoming just the fourth craft (if Japan's current Hayabusa-2 mission is a success) to make a controlled landing on an asteroid.

Then, in 2021, NASA would launch another probe, called the Double Asteroid Redirection Test, or DART. When it arrives in late 2022, the 660-pound probe would crash into Didymoon at a speed of more than 13,000 miles per hour, likely creating a crater and slightly changing the path of the asteroid's orbit. AIM would continue to collect data on Didymoon, providing valuable information on the physics of redirecting asteroids in space.

2. NASA is trying to avoid a chain reaction of asteroids

Originally posted here:

NASA wants to deflect an asteroid in 2022: 4 reasons why