Would it be possible to use electromagnets on the outside surface of the ISS to stay anchored to it or is it made with non-ferromagnetic materials?


3 Answers 3


Sadly, they are made mostly of aluminum, as explained in this quora answer and also on this NASA page.

Because each of the aluminum-can shaped components of the Station has to be lifted into orbit, minimizing weight is crucial. Lightweight aluminum, rather than steel, comprises most of the outer shell for the modules.

  • $\begingroup$ Hmm... Maybe not total sadness - see this question. $\endgroup$
    – uhoh
    Oct 8, 2016 at 1:37

Let's see if there are any advantages to using magnetic grapples instead of the current system.

Those magnetic grapples would have to be electromagnets. Permanent magnets strong enough to prevent an astronaut from flying away would be very hard to remove.
So instead of passive elements (two short cables and carabiners), you'd need a power source, electric cables and switches, and two magnets, plus a backup (two short cables and carabiners) in case you have a power failure. So you'd add several kg worth of equipment, plus two more cables to get tangled in.
On the plus side, you'd be able to place the magnet anywhere on the hull (if you made the entire outer hull/Whipple shield out of steel), and you'd save a few seconds because you don't have to manipulate a carabiner through those really thick gloves.

  • $\begingroup$ The hull doesn't need to be ferromagnetic, and the EVA astronaut doesn't need an electromagnet. The magnets could be operated by an astronaut on the inside of the hull. They are only needed where the EVA astronaut is at the moment. Could that work? $\endgroup$
    – LocalFluff
    Oct 8, 2016 at 8:54
  • $\begingroup$ Most of the hull surface is not reachable from the inside. The modules are covered in instrument racks. $\endgroup$
    – Hobbes
    Oct 8, 2016 at 9:28
  • $\begingroup$ Magnetic "tracks" from the airlock could help the space walkers get quickly to the vicinity of where they need to go, and use tethers as today from there. But a spaceship better be designed for that from the beginning. If magnetic anchoring is useful, maybe a test could be done at the ISS? Not much electric power seems to be needed, unless working through the hull increases that dramatically. But powerful magnets could interfere with other equipment. An arm could transport them instead, and have other uses. Maybe magnets are good for anchoring to metallic asteroids like Psyche? $\endgroup$
    – LocalFluff
    Oct 8, 2016 at 9:39

Magnetic grapple points could be quite useful. They would not be as failure resistant as caribiners so they would likely only be used for anchoring tools and equipment, not crew.

A small patch of magnetic stainless would likely wight less than a carabiner eye-bolt. Or existing eye bolts could be made of magnetic SS.

The magnet would not need to be an electromagnet. In precision machining, instruments are routinely held in position by permanent magnet mounts. The magnetic field of the mount is engaged or disengaged mechanicaly. They are easier to reposition than Velcro.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.