AIM Didymos

ESA is planning to launch Asteroid Impact Mission (AIM) in October 2020, to evaluate planetary defence techniques to prevent asteroid collision, which could include changing the orbit of asteroids headed towards earth.

The agency has started preliminary design work on AIM spacecraft, which will travel to the paired Didymos asteroids that are expected to travel within 11 million kilometres of the Earth in 2022.

The binary asteroid system is orbited by a moon called ‘Didymoon’.

AIM will carry out visual, thermal and radar mapping of the moon to create plans of its surface and interior structure. It will also launch a lander on to the small body.

In addition, CubeSats will be deployed to gather scientific data in the vicinity of the moon.

AIM is said to be Europe’s contribution to the Asteroid Impact and Deflection Assessment mission (AIDA).

The NASA-led part of AIDA will launch a double asteroid redirection test (DART) spacecraft to the Didymos binary system in late 2022. DART will crash into the asteroid moon at around 6,000m per second.

"We will gain insight into the kind of force needed to shift the orbit of any incoming asteroid, and better understand how the technique could be applied."

ESA mission head Ian Carnelli said: "AIM will be watching closely as DART hits Didymoon.

"In the aftermath, it will perform detailed before-and-after comparisons on the structure of the body itself, as well as its orbit, to characterise DART’s kinetic impact and its consequences."

The results will allow scientists to understand how an asteroid will react to this type of energy.

"In addition, DART’s shifting of Didymoon’s orbit will mark the first time humanity has altered the dynamics of the solar system in a measurable way," Carnelli added.

"We will gain insight into the kind of force needed to shift the orbit of any incoming asteroid, and better understand how the technique could be applied if a real threat were to occur."

AIDA is a joint international collaboration of the ESA, German Aerospace Center (DLR), Observatoire de la Côte d´Azur (OCA), NASA and John Hopkins University Applied Physics Laboratory.

The programme is designed to study a spacecraft impact on a potentially hazardous near-earth asteroid and measure the deflection caused by the impact.


Image: AIM and Didymos binary system. Photo: courtesy of ESA-Science Office.