NASA and the European Space Agency (ESA) had already announced back in 2015 that they would be collaborating on the Double Asteroid Redirection Test (DART) mission, which will see the duo send a craft to a binary asteroid system called Didymos, launching in 2021. The asteroid has been described as “non-threatening”, but a close approach from the space rock will allow the international space collaboration, known as Asteroid Impact and Deflection Assessment (AIDA), to test their machine by knocking Didymos off its course. By doing so, and if the mission is successful, NASA and the ESA will then be able to send a spacecraft to an Earthbound asteroid in the future and knock it off of its course, away from our planet.
Now, recent discoveries have reiterated the need for such objectives.
AIDA has been analysing the Japanese space agency’s, JAXA, mission to the asteroid Ryugu.
Then JAXA’s spacecraft, Hayabysa2, landed on Ryugu, it left a much larger impact crater than was expected.
This essentially proved that the gravity of Ryugu was stronger than expected, and might effect how AIDA can move a space rock.
Dr Patrick Michel, who is presenting in sessions on planetary defence at EPSC-DPS 2019, said, “The impact with Hayabusa2 showed that there was no cohesion on the surface and the regolith behaved like pure sand.
“Gravity was dominating the process, rather than the intrinsic strength of the material from which the asteroid is made.
“If gravity is also dominant at Didymos B, even though it is much smaller, we could end up with a much bigger crater than our models and lab-based experiments to date have shown.
“Ultimately, very little is known about the behaviour of these small bodies during impacts and this could have big consequences for planetary defence.”
READ MORE: NASA spots a 1,410ft ‘hazardous’ asteroid barreling towards Earth
Nancy Chabot, DART Mission Coordination Lead and Planetary Scientist at Johns Hopkins University Applied Physics Laboratory, said: “DART’s target, Didymos, is an ideal candidate for humankind’s first planetary defence experiment.
“It is not on a path to collide with Earth, and therefore poses no current threat to the planet. However, its binary nature enables DART to trial and evaluate the effects of a kinetic impactor.”
Didymos is a binary asteroid system, which means that one asteroid orbits a bigger one.
In this case, DART will hit the smaller asteroid, which is about 160 metres in length, “nine times faster than a bullet, approximately 3.7 miles per second” according to a statement.