You probably weren’t worried that there might be a nuke hanging out in a satellite over our heads right now. There isn’t—that we know of. But that knowledge gap was enough for an MIT physicist to publish a paper in Nature proposing a theoretical device that could fly alongside a satellite and determine whether it’s carrying a nuclear weapon.
“But,” you might argue, “the 1967 Outer Space Treaty explicitly bans nuclear weapons in space!” While that’s true, there is a glaring loophole: we have no way to verify whether anyone has already put one up there. That treaty could have been defied 10 times over by now, and we would have no idea.
To combat this, MIT nuclear physicist Areg Danagoulian proposes taking advantage of the Van Allen radiation belts, which are regions packed with high-energy particles trapped by our planet’s magnetic field. As satellites pass through them, those particles naturally bombard everything in orbit. If a satellite is carrying uranium or plutonium, the incoming protons would knock loose bursts of neutrons in a process called spallation.
This means that a satellite carrying a nuclear weapon would have a specific signature that Danagoulian’s proposed device could detect with specialized neutron detectors, while distinguishing that signature from all the other radiation bouncing around in space.
There Could Be Nukes Hidden in Satellites, and Scientists Want a Way to Check
According to Danagoulian’s calculations, a detector that Phys.org describes as roughly the size of a large encyclopedia could identify a nuclear weapon with about 99 percent accuracy after orbiting within roughly 4,000 meters of a suspect satellite for about a week. Get within 1,000 meters (or deploy several inspector satellites), and it’ll do its job in a matter of hours.
In case you were wondering, a nuclear explosion in low Earth orbit would flood space with radiation, taking down communications and GPS satellite systems, weather monitoring systems, and Internet satellites, which would go down as well. This would disrupt all life on Earth as we know it, likely setting us all back decades as we scramble to replace those nuked satellites.
It should be noted that this is not a finished technology ready for launch into space. It’s a study strictly about the theoretical feasibility of such a device. But if the concept proves to be practical enough to someone in charge, it could finally give us a way to verify that there really aren’t any nukes floating precariously over our heads.