Giz Explains: How To Catch An Asteroid

Giz Explains: How To Catch An Asteroid


That Pet Rock of yours lose a bit of its lustre over the years? Not to worry, NASA plans to put one big enough for the whole world to share in orbit around the moon by the start of the next decade. Here’s how.

You Should Do This If:

You’ve ever wanted to study a 7m long, 450-tonne space rock up close, maybe unlock some secrets of the early galaxy and jump start an entirely new space-based industry of asteroid mining.

Moment of Satisfaction:

Giving the moon a satellite of its very own or, as Xzibit would say, “Yo dawg, I heard you like moons so I got a moon for your moon.” It’s going to be an asteroid orbiting a moon, orbiting a planet, orbiting the sun — put there through human ingenuity and man-made technology — which is pretty freakin’ awesome.

Biggest Pain in the Arse:

Since the asteroid we capture will likely be spinning on more than one axis, making it nearly impossible to set into a stable orbit around the moon, the Asteroid Capture and Return (ACR) spacecraft sent out to retrieve it will have to precisely de-spin the rock using reactionary engines before towing it back.


Materials and Tools Required

  • 1x Near Earth Asteroid, roughly 7m in diameter — small enough to pose no threat to humanity in the event that the mission goes all Armageddon on us and the asteroid smacks into the planet.
  • 1x ACR spacecraft, powered by a pair of deployable solar panels and driven by a xenon-gas Hall-effect ion thruster.
  • 1x 15m diameter deployable capture bag for securing the asteroid as it’s being towed back to Earth
  • 1x Atlas V rocket


Difficulty and Cost

It will cost $US2.6 billion in total, on par with the massively successful Curiosity Mars rover mission. $US100 million has already been set aside in the FY2014 budget for ACR protoype design and testing.

The mission will take most, not all, of our cunning to accomplish but is within the realm of our current technology. “Return of a near-Earth asteroid of this size would require today’s largest launch vehicles and today’s most efficient propulsion systems in order to achieve the mission,” said Chris Lewicki, CEO of Planetary Resources and former flight director for NASA’s Spirit and Opportunity Mars rovers. “Even so, capturing and transporting a small asteroid should be a fairly straightforward affair.”

Building It


First, load the ACR onto an Atlas V rocket and blast it into space. The ACR will separate from the rocket and spend two years spiralling away from Earth as its ion thrusters gain momentum. Next, use the moon’s gravitational well to slingshot deeper into the solar system and meet up with the asteroid almost two years later in 2019.

Once contact with the target asteroid has been confirmed, deploy the capture bag and gently ensnare the space rock using the ACR’s manoeuvring thrusters. stabilise the asteroid by de-spinning and securing it within the capture bag — this process should take about 90 days. Point the ACR towards Earth and start towing the rock to its new home circling the moon. Since the asteroid is going to add an extra 500 tons of mass to the spacecraft, the return trip will take between four and six years.

Once home, the ACR will once again slingshot around the moon to release the rock into a stable orbit whereupon manned missions will begin. Researchers will be shuttled to the moon aboard the Orion crew capsule and, barring any massive delays, we should be standing on our very own captive asteroid by 2021.

Or if you’re lazy:

Go rent Armageddon and remember why we’re sending robots out there first.

[Earth Sky, Space, Space, Wikipedia]

Top picture: Mopic/Shutterstock; bag deploymant image: NASA; capture image: Rick Sternbach/KISS


The Cheapest NBN 50 Plans

It’s the most popular NBN speed in Australia for a reason. Here are the cheapest plans available.

At Gizmodo, we independently select and write about stuff we love and think you'll like too. We have affiliate and advertising partnerships, which means we may collect a share of sales or other compensation from the links on this page. BTW – prices are accurate and items in stock at the time of posting.