After the ISS: What Comes Next?

There are few among humanity’s many scientific and engineering accomplishments that are both as beneficial and as inspirational as the International Space Station. It has not only served as the testing ground for any number of important experiments and discoveries, it has also been our outpost in space for over a quarter of a century.

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But the ISS is old. Perhaps we should be more respectful and say “venerable”, but it amounts to the same thing: it’s aging and will, within not so many years, start to suffer from the kinds of creakiness that not only will limit its ability to serve as a functioning laboratory, but could threaten its ability to safely host humans at all.

So, as magnificent as it is, the ISS is due to be deorbited (a polite euphemism for dragging nearly a million pounds of space station to a fiery death) in early 2031. But what will follow it? There are a number of possible answers, mostly from the commercial space world. Since I recently got to talk to someone who is working on one of those possible solutions, I thought it would be fun to take a gander at some of the things being worked on to take the ISS’s place when it is gone (functionally, anyway. Nothing can take its place in our hearts).

Select Your Structure

When it comes to ideas about what could replace the ISS, the sky is most certainly not the limit. Many different concepts are being worked on. Some of these will look familiar to anyone who has seen pictures of the ISS or its predecessor Mir. After all, both of these long-lived stations proved that modular stations, built up out of multiple individual segments docked together, can work.

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That’s the basis for Axiom Station and Orbital Reef, two of the designs being pursued. Axiom Station comes, appropriately, from Axiom Space, while Orbital Reef comes mostly from Blue Origin and Sierra Space, with additional partners in Boeing and Redwire Space, among others. 

Some look even farther back for inspiration, to the single-module structures that made up the world’s first space stations, NASA’s Skylab and Roscosmos’s series of Salyut stations (which also formed the base design of Zarya, the first piece of the ISS sent to space in 1998). That’s closer to what the company Vast has in mind for its Haven-1 station, a single module offering about 1,600 cubic feet (45 cubic meters) of habitable space. Haven-1 is currently scheduled for a 2026 launch, making it the first of these concepts to go up (nothing else has a launch date prior to 2028).

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There’s also Starlab, being designed by a conglomeration of Voyager Space, Nanoracks, and Airbus. I think of this one as sort of more like an Apollo spacecraft: two modules, one of which is habitat and one of which is a service module providing power and propulsion.

But what if we didn’t look to past space vessels as inspiration? What if, instead, we want to try something completely new? That’s what the Aurelia Institute is working on with its TESSERAE technology, designed to create a self-assembling space habitat. I recently got to chat with Dr. Ariel Ekblaw, the founder of Aurelia, and I have to say I find this design to be one of the more interesting ones being developed. It’s practical, yes, but it’s also cool.

Puzzle Pieces in Space

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So you want to run some biomedical experiments in space. Not surprising, this is one of the major things the ISS does because it turns out there are certain things you can only study in the microgravity environment of low Earth orbit. Only…space on the ISS is limited (ironically), and even if you get your experiment up there, the only way to run it is to train an astronaut to do it for you.

Dr. Ekblaw would like to see that change. As she points out in her 2025 TED Talk “How to Build in Space for Life on Earth”, thanks to the boom in reusable commercial rockets, the cost of getting things to space has dropped dramatically. So getting experiments and even people like scientists or postgrads into space isn’t what would be causing the holdup on your experiment. “The bottleneck isn’t rockets anymore,” says Dr. Ekblaw, “it’s real estate.” There’s simply a lack of useable space on the ISS, both for people and for projects.

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To Dr. Ekblaw’s thinking, slowly assembling another massive station piece by piece isn’t the solution. Instead, she’s been working on her TESSERAE, Tessellated Electromagnetic Space Structures for the Exploration of Reconfigurable, Adaptive Environments (space agencies aren’t the only ones who delight in a perfect acronym), for nearly a decade. It started as her PhD thesis at MIT, grew through R&D at the Aurelia Institute, and now it’s a focus of a new company, Rendezvous Robotics, working to scale and commercialize the tech.

TESSERAE are tiles which can be carried into space stacked in a big ol’ pile and deployed into the void, where they will assemble themselves into buckyball shapes (either using powerful magnets to attract each other or, for potential future models, using some sort of propulsion). Those buckyballs can then either operate as an individual structure or can connect to other assembled buckyballs to create a larger, modular structure. You could literally build a station like a giant self-solving puzzle in space!

Design A Station

Obviously the fact that a space station could potentially put itself together in orbit is cool. It is, frankly, what I love most about this design. But it’s also immensely adaptable, and that is an undeniably attractive feature if you’re going to order yourself up a space station.

Want a bigger station? Have more buckyball structures! Want a single buckyball? Easy-peasy! Want the individual buckyballs to be bigger? Why not! Want your space station to come pre-furnished with life support systems, lab space, and furniture built into the tiles themselves, ready to be unfolded and used immediately? There’s a TESSERAE design for that! Prefer your TESSERAE buckyball to simply provide a rigid support structure while you create your own inflatable habitation space within it? Oddly specific goal, but absolutely doable!

Talkin’ Timelines

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So how close are we to seeing tile-based space stations putting themselves together in orbit like a possessed LEGO set? I asked Dr. Ekblaw what the timeline looks like and, as with many tech innovations, there’s good news and bad news. The bad news is that it’s going to be a while before anybody can place an order for a specifically-designed TESSERAE space station. But the good news is that several of the steps along the way to that goal have already been made or are scheduled.

For one thing, the Aurelia Institute has already built a full-sized mock-up of one of these habitats here on Earth. It’s been on display in Boston, Seattle, and Vancouver and comes outfitted with some of the specialty tiles that future space-dwelling folks might want, like a panel to grow plants and one to store food. And, you know, a window. Windows are good too.

Aurelia has also had the chance to test small versions of the TESSERAE tiles in space on the ISS, once in 2020 and once in 2022. They’re due to be tested again in 2026. If you watch the TED talk you can see actual video from the space station of small TESSERAE pulling themselves together while an astronaut looks on.

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As for building a full-size mockup in space? Five years, says Dr. Ekblaw—as long as you don’t want to have humans in it. The idea is to build a complete, fully-equipped orbital biolab that will not host a crew, to prove it can be done safely. This demo model will be attached to an existing space station and five years down the road, of course, that station might not be the ISS. Perhaps it will be something built by Axiom or Vast or one of the other companies currently working on ideas.

Then in perhaps seven years (though Dr. Ekblaw says looking more conservatively it may be more like ten), a TESSERAE habitat will be ready for human occupation, a buckyball home among the stars!

Hopeful Futures

I have to say, I kind of love the idea of there someday being a string of variously-configured TESSERAE-built buckyball stations in Earth orbit like a giant necklace of bizarre pearls. And if there are other, more traditionally modular space stations sprinkled in then so much the better. I’m all in favor of there being more room for more people in space.

Beyond Earth orbit, there’s also the chance for these same designs and technologies to get put to work when it comes to humanity’s broader ambitions for space, the Moon and Mars. Could a station based on Orbital Reef someday sit in orbit around the Moon? Could a Starlab-derived interplanetary vessel someday carry people to Mars? Could a rocket someday drop TESSERAE onto the surface of the Red Planet to create the shell of a Martian base? MAYBE.

And if not, it’s not like this is wasted effort. Technologies and products spun off from ones originally created in the pursuit of space exploration are present in our everyday lives, from water filters to shock-absorbing helmets to LASIK eye surgery. Earth benefits from this research too.

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Dr. Ekblaw envisions farms of solar-paneled TESSERAE in space beaming the power of pure sunlight to the ground as an endless 24/7 supply of clean energy. Or creating such vast stretches of orbital real estate that pollution-heavy industries could be moved off-planet, where they cannot harm Earth’s ecosystems. Or even something as basic as having easy-to-transport, rapidly-assembling TESSERAE shelters that can be shipped into disaster areas on Earth to provide a temporary home for those who have lost theirs. “The first priority is to use TESSERAE in service of Earth,” she said when I talked to her.

When you set out to create something new, you can’t always predict what will come of it. All of these efforts to create a successor to the International Space Station will, hopefully, result in broadening humanity’s foothold in outer space, but it also might lead to a better world closer to home as well. We’ll just have to wait to find out.

(But come on, the image of Earth having an orbital necklace of oddly-shaped buckyball pearls is pretty great, no?)