I’d like to do the math.
One day, years from now but seeming too soon, the International Space Station will come to an end. But this ending will also be a story about beginnings. NASA having led the way, learning to live and work in space, others will follow, building on what was learned. If a project as daunting as building and operating the ISS is to have meaning, there must be a legacy of expanding human activity in Earth orbit. Our continued human presence in Earth orbit will mean even more advances in medicine, science, and technology, as well as new directions in manufacturing and possibilities we have yet to imagine.

NASA astronauts would still do research in low Earth orbit, only aboard a commercial space station or many stations. With this inevitable shift come expectations of what happens along the way. One expectation is that renting research space shared with others will provide a savings to NASA versus owning, running, and occupying their own orbiting facility. Now we have an idea of just how much the savings might be or a goal for starters.
Recently, Phil McAlister, NASA director for commercial spaceflight, said –
“…we can use that savings – that we project to be on the order of a billion to a billion-and-a-half dollars [annually] for our deep space missions and aspirations.”
If your teacher ever leaned in during an exam in 4th grade and said, “doesn’t “B” look like it could be right?” this is what NASA just did. It’s not the first time NASA has given out answers to an exam. Sometimes the answer is telling everyone how much funding NASA expects and that they want two partners. What would be a good answer? Do the math – and set your proposal at about half the funding NASA says they expect. (Also, if the teacher says the answer is “fixed-price,” don’t fill in the circle for “cost-plus.“) This math is not complex because it simply starts with the goal, getting the thread going about how you get there.
Experts will argue how reality may not match ambitious goals. Or we can debate anchoring, how a first suggestion biases everything that comes after. Still, arguing over your customers’ expectations is probably not a winning strategy. Meeting and exceeding expectations is.
Rather, any NASA statement with a dollar number is helpful, “bounding” a challenge within an expectation. That’s NASA-speak for saying the conductor is tapping his baton on the podium so the orchestra can stop the cacophony of tuning up. Everyone, attention, please. If you’re lucky, what follows might even be everyone on the same sheet of music. At the least, budget goals are a good reminder that budgets are just as real as the laws of physics. Funds either exist, or not, or there is a budget case for stakeholders, or not, just as much as you have enough propellant to get to orbit, or not.
The question follows, if there are commercial space stations in NASA’s future, would you like to do the math? Let’s do the math. Along the way we can compare some unstoppable forces to some immovable objects.
But first, we have to unbury some bodies. For this, we go to a NASA budget line called Space Flight Support. In plain English, Space Flight Support is everyone and everything behind the scenes, the people, buildings, and equipment that make possible what’s out front. When the Shuttle program ended, this went up, not down. This would seem counter-intuitive, like saying the business was shut down, but a lot of the folk at corporate headquarters will be staying around. It makes more sense to say the war has ended, but we’re keeping a standing army just in case. For starters, we would bump this up about a **quarter-billion a year a couple of years before the ISS is de-orbited. This repeats what happened as the Space Shuttle program ended, if a little on the low side.
Then, at the meat of the matter, there are three parts to the International Space Station costs: (1) operating the station, (2) getting to and from the station, and (3) the cost to perform the bread-and-butter research that is why we are there. Of course, these go to zero once the ISS ends, but don’t worry, they return on the new commercial space stations. There are more bumps, adjustments, and twists and turns, of course. Will there be a budget for the ISS the year after its de-orbited? Obviously, yes, just as happened with the Space Shuttle, a cost to clean up after the party is over. We’ll need to look at other happenings as well, over at a new Gateway in lunar orbit. But these are not where the real action is.

Finally we come to the new commercial space station (or stations). What might NASA moving to commercial space stations look like? When the Space Shuttle built the space station and delivered cargo and crew, NASA used its own truck, government property, with government drivers, arriving at a government facility. Nowadays, NASA getting crew and cargo to the ISS is more like buying an airline ticket, so the airplane is not yours, and now the pilot is optional. Moving NASA research to a commercial space station (or stations) will mean arriving at private property. Which brings up just how you arrive?
It’s probably safe to assume that crew and cargo will arrive at the new commercial station the way they do today. Inevitably, someone will ask if they can “bundle” the car and the hotel room all together at SpaceLine.com (Shatner will do the commercials.) This will not change where the math might go at first blush or how it flows from here. As NASA would be doing less research, say we spend one-third of today’s NASA budget on rides to the commercial station. That station needs operations and maintenance, so we might say it’s about half of current ISS operations while we are on a roll. Then to top it off, we move half the research today to the new station (by dollar amount).
Does it look like “B” really is the right answer? Yes*. NASA could see a savings of a “billion to a billion-and-a-half dollars [annually]” once it moves to commercial stations post-ISS. At least at first blush, inside all these “what-ifs.” The multi-verse is rather large. Needless to say, turning all these particular knobs and dials here and there, and diverting power to the deflector dish from the starboard nacelle, is just one way to do the math. There are probably too many solutions to count, though a glutton for punishment may try. What will matter is where most of these numbers lean in most scenarios.

One afternoon years from now, we will all be glued to a scene unfolding at the ISS, a portion of it separating at the forward berthing port. Leaving the nest, a smaller but still very capable set of modules will thrust safely away, leaving the mothership behind. We will be witnessing the birth of a new space station with shiny new dreams.
Or perhaps the new space station is something else entirely. Might a SpaceX Starship, decked and outfitted, make an excellent research hub? Why upgrade in space when you can bring the whole thing back to Earth every so often, rip out the old technology, then launch it again. Maybe even that is passe, with life moving much faster, so you just de-orbit the “old” new-one after some years and launch a whole “new” new one – call it the iCSS 13. No one fixes things when it’s cheaper to just get a new one.
Yet, beyond the technical and budget challenges, a move from an international station to a US commercial station means even bigger questions. Companies with an eye on a growing human presence in orbit may offer our international partners the same capability they provide NASA. Will these prove to be eager customers? That would be atop providing space, ample power, and arranging rides to new business in pharmaceuticals, manufacturing, and industries to come. Companies will have to capture all this in their second set of books, beside any NASA scenario. All this assumes funding going up slightly every year for NASA in the first place, and translating into commercial space stations.
“The surface of the Earth is the shore of the cosmic ocean. From it we have learned most of what we know. Recently, we have waded a little out to sea, enough to dampen our toes or, at most, wet our ankles. The water seems inviting.”
Carl Sagan
We have dampened our toes at the shore of the cosmic ocean, inviting our international partners first. Now it’s time to invite everyone else.
*This analysis came in at 1.6 billion dollars a year in nominal dollars, or 1.3 billion a year savings in 2021 dollars, starting two years after the ISS is de-orbited (assuming 2031.)
**Edited 2/8/2022 for a typo – was “quarter-million,” should have been “quarter-billion.” The number in the calculations and the graph was entered correctly as a quarter-billion for the Space Flight Support bump-up/movement of funds as the ISS ends.