It’s not cheap to get stuff into space, especially stuff that’s really big and heavy. So, if we’re looking to build the next generation of space stations, why not use the stuff that’s already up there?
IEEE Spectrum reports that payload management firm NanoRacks, spacecraft hardware manufacturer Space Systems Loral and rocket manufacturer United Launch Alliance have all teamed up for a new, NASA-funded project called Ixion. The goal is to use rocket fuel tanks already in orbit as future space habitats for astronauts. It might sound a little crazy, but it makes sense. These fuel tanks are sturdy, and they’re already airtight and pressurized.
They’re also huge: The hydrogen fuel tank for a Centaur upper stage has approximately 54 cubic meters of interior volume. For the sake of comparison, the BEAM inflatable module NASA just added to the space station has an interior volume of 16 cubic meters. So a used fuel tank would have almost four times the space of that habitat onboard the ISS. Plus, it’s already there, so you’re not spending millions to get it up into space.
"Most people ignore these upper stages, but they're actually very sophisticated spacecraft. They have their own guidance systems, their own propulsion, their own attitude control systems, and they have large, lightweight [propellant] tanks that can handle atmospheric pressure,” NanoRacks’ chief designer Mike Johnson told IEEE Spectrum. “[These tanks] are durable and tough: obviously, they're made to take launch loads, which is six or seven gees. Typically, the upper stage orbits with the payload that's on top of it, and eventually it gets deorbited as a piece of, at that point, space junk. But it's really a shame, because these things are huge, with this huge volume that you could use for a space station."
It’s not a new idea (the U.S.’s first space station, Skylab, was designed from an unused Saturn V rocket fuel tank, and Wernher von Braun actually pitched the idea in the 1960s), and as private companies look to expand into orbit, all parties think it could be the most affordable route to give the International Space Station some new neighbors.
The tanks would obviously need some retrofitting to make them usable, but it’s still an amazing idea. Basically, you launch a rocket you were going to launch anyway, then use the tank as a habitat. Two birds, one stone. Or rocket. Whatever, you get the point.
The team is trying to work out the kinks of feasibility right now, and a potential test of this tech could happen as soon as the next few years.
(Via IEEE Spectrum)