AIM: the mission to deflect an asteroid

ESA and NASA are collaborating on a future mission to examine how asteroids might be deflected away from Earth.

The AIM spacecraft analyses the moment of impact in infrared. Credit: ESA -
Published: June 30, 2017 at 12:00 pm
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The detection of asteroids remains a primary concern for astronomers and space agencies, as new methods are being developed that could save Earth from a massive impact. One such mission being developed by ESA and NASA is the Asteroid Impact & Deflection Assessment (AIDA) mission.


This initiative will see two spacecraft launched into space to measure how human technology could alter the course of an asteroid before it hits Earth.

Binary asteroid 65803 Didymos provides one such opportunity, as this asteroid and its orbiting moon will come within 16 million kilometres from Earth in October 2022.

The AIDA mission is split into two separate projects.

The first is ESA’s Asteroid Impact Mission (AIM), which is due to launch in October 2020.

This spacecraft will arrive at the binary system to carry out visual, thermal and radar mapping of its moon, informally named Didymoon.

The second part of the mission is NASA’s Double Asteroid Redirection test (DART), which will see a probe approach the binary system and smash straight into the moon at a speed of 6 kilometres per second.

The AIM spacecraft will observe the effect of the crash, analysing the structure of the moon and how its orbit has changed.

This will give scientists an idea of how future asteroids might be deflected out of Earth’s path.


The data collected would form a baseline for future planetary defence studies, as well as providing information on an asteroid’s strength, physical properties and structure.


Iain Todd, BBC Sky at Night Magazine
Iain ToddScience journalist

Iain Todd is BBC Sky at Night Magazine's Content Editor. He fell in love with the night sky when he caught his first glimpse of Orion, aged 10.


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