How It Works
ARM spacecraft concept 1

NASA’s daring mission to capture an asteroid

ARM spacecraft concept 1

NASA’s next big plan for space exploration is the Asteroid Redirect Mission (ARM), which is on track to send a robotic spacecraft to capture an asteroid and redirect it into the Moon’s orbit in 2020. Astronauts will then visit it aboard an Orion spacecraft in the 2020s and collect samples that could hold clues to the origins of our Solar System and life on Earth. It is also hoped that the mission will prove a number of the capabilities humans will need to reach Mars, something NASA is hoping to achieve in the 2030s.

Along with citizen astronomers, NASA has been using telescopes to study the thousands of near-Earth asteroids and identify good candidates for the mission. The space rock it is currently planning to target is the 400-kilometer-wide asteroid 2008 EV5, and it hopes astronauts will be able to bring back a two-to-three-meter, 20-ton boulder from the surface. Although it is hoped the mission will also demonstrate techniques for defending Earth from impacts in the future, the asteroid chosen for the ARM mission won’t pose any threat to us. It could remain in the Moon’s orbit for hundreds of years and even if it did approach Earth, it would be so small that it would burn up in the atmosphere and disintegrate before reaching the surface.

Asteroid Redirect Mission
Asteroid Redirect Mission

Robotic spacecraft concepts

ARM spacecraft concept 1
ARM spacecraft concept 1

The first of the two concepts for the ARM robotic spacecraft involves capturing a small asteroid in a 15-metre (50-foot)-long inflatable bag before towing it toward the Moon’s orbit. The second uses robotic arms to retrieve a small boulder from the surface of a much larger asteroid. Both concepts use advanced solar electric propulsion (SEP), an efficient way to move large payloads into deep space that could be crucial for getting humans to Mars. It involves using the craft’s many solar panels to generate electricity, which is then used to ionise the atoms of propellant gas. Magnets are then used to push the ions out the back of the craft and repel them away to create thrust. Although the thrust is weaker than that produced by traditional rocket fuel, it can be sustained for longer to build up acceleration, making it ideal for long deep-space missions.

ARM spacecraft concept
ARM spacecraft concept 2

Take a look at how the mission will work with NASA’s ARM concept animation….

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