Bigelow's BEAM (the big bump at center-right) will soon provide 2% of ISS's living space. Image source: Bigelow Aerospace.

Moving day is fast approaching. Sometime in 2023 or 2024, the Russians have said they will abandon the International Space Station. Assuming they carry through on this plan, detaching their modules from ISS and using them to build an all-Russian station, the station could soon become uninhabitable.

That's then, however. For now, the International Space Station is still growing -- thanks to Bigelow Aerospace.

Space exploration (literally)
Last week, a SpaceX rocket (yes, the same one that just landed on a boat) delivered to ISS its first-ever Bigelow Expandable Activity Module (BEAM). Attached to the space station on Saturday, the 1.5-ton, 8-foot-diameter BEAM module will later be inflated to its full size, 10 by 13 feet, to add 565 cubic feet of living space for the ISS crew.

To put that number in context, think of a room with an 8-foot ceiling: "565 cubic feet" then works out to a room the size of a 10-by-7-foot walk-in closet. It will expand the internal pressurized volume of ISS (currently 32,333 cubic feet) by just under 2%.

Now, that may not sound like much, but consider this.

Real estate prices are in freefall (still literally)
ISS cost more than $100 billion to build. Bigelow's BEAM, in contrast, was built for $17.8 million. Were all of ISS to be constructed from BEAMs today, therefore, the living space portion of ISS could be recreated for a cost of just over $1 billion. 

Granted, that cost might not include all the high-tech wizardry -- solar panels, Stephen T. "C.O.L.B.E.R.T."  space treadmill, and so on -- that enables ISS to function. But counting just plain living space, cubic foot for cubic foot, Bigelow is about 100 times cheaper to build than ISS proper.

Astronauts use the Combined Operational Load Bearing External Resistance Treadmill (COLBERT) to stay in shape in space. Image source: NASA.

The future of space construction?
Now, Bigelow's BEAM is just a prototype, and it remains to be proved that an "inflatable" space station will stand up to the hardships of space as well as a "real" space station. But that's why BEAM is up there. NASA will evaluate BEAM's performance over the next two years to see if BEAM offers a more economical way to build real estate in space.

And longer term, if all goes well, BEAM could provide the blueprint for a whole new way of building space stations, permitting America, and the companies that conduct experiments aboard the International Space Station today, to continue operating in space long after the Russians have departed.

Fast forward to the future
Already, with its ISS experiment just barely begun, Bigelow is pressing ahead with new ventures. In cooperation with United Launch Alliance -- the joint venture formed by Boeing (BA 0.32%) and Lockheed Martin (LMT -1.90%) in 2005 -- Bigelow plans to send up a much larger BEAM module, dubbed the B330, aboard a ULA Atlas V rocket in 2020.

B330, so named because it will contain 330 cubic meters (or 12,000 cubic feet) of usable space within its inflatable walls, will be much larger than the BEAM module currently in place on ISS. Roughly speaking, if BEAM is the size of a walk-in closet, then B330 will be as large as two New York City-size one-bedroom apartments, measuring roughly 25 by 30 feet in square footage.

Attached to ISS (NASA permitting) it would increase ISS's usable living space by 30%. But B330 would not necessarily need to be attached to ISS -- and that's the point.

The future of space
Although Bigelow would love to work with NASA  and integrate its first B330 into ISS, the company has bigger plans for the module: "B330s, which will initially be deployed and tested in LEO, will be used as private sector space stations that will conduct a wide variety of commercial activities."

You read that right. Not only can Bigelow's module be used to build a space station at a fraction of the cost it took to build ISS. With help from Boeing and Lockheed Martin, Bigelow also says it will use BEAM modules to build a space station.

Tory Bruno,  CEO of the Boeing/Lockheed Martin joint venture ULA, adds that within a B330-based space station, companies will one day find "opportunities for space research in fields like materials, medicine and biology." Long after ISS is gone, Bruno says B330 will provide a place for "countries, corporations and even individuals" to live in Earth orbit, "effectively democratizing space. We can't begin to imagine the future potential of affordable real estate in space."

Except that already, they're doing just that -- imagining the future of Bigelow bungalows in space."

Two Bigelow B330 modules, joined at the hip, would offer more than half the living room contained on the entire current International Space Station. Three such modules, arranged tic-tac-toe, would be bigger than ISS -- but cost just a fraction of ISS's $100 billion price tag. Image source: Bigelow Aerospace.