Nasa plans to knock an asteroid out of orbit by launching a spacecraft to deliberately crash into it in what is thought to be the first ever test of a planetary defence system.
The ambitious mission is set to prove whether the Earth could be defended if an asteroid was on course to devastate the planet by smashing into its surface.
A project called Double Asteroid Redirection Test (DART), which aims to throw an asteroid off course in three years’ time, has been approved by the space agency.
Nasa expects to launch the probe into space between December 2020 and the following May, and will eventually collide with an asteroid known as Didymoon.
Didymoon is a 150-metre moon asteroid and is part of a double asteroid system which will be within 11million kilometres of Earth upon impact, Nasa has said.
“The collision will change the speed of the moonlet in its orbit around the main body by a fraction of one percent, enough to be measured using telescopes on Earth,” the space agency added as it released a description of the mission.
“[The spacecraft] will intercept Didymos’ moonlet in early October 2022, when the Didymos system is within 11 million kilometers of Earth, enabling observations by ground-based telescopes and planetary radar to measure the change in momentum imparted to the moonlet.”
The spacecraft will also be accompanied by a European Space Agency (ESA) spacecraft called Hera, which will be responsible for collating data about the asteroid.
Following the crash, scientists are to study how Didymoon's path around its parent rock changes. This will help researchers understand how to develop strategies humans could use to deal with a space rock that is aimed directly at Earth.
The launch of the special probe is scheduled to take place between December 2020 and May 2021.
