We Toured the World’s First Inflatable Space Station. Here’s What It Was Like.

An inflatable space station? It’s not as crazy as it sounds. Colorado-based Sierra Space is planning to replace the International Space Station (ISS) once it retires at the end of the decade with a series of inflatable living quarters that will let scientists, artists, and others live and work for weeks.

For its first act, Sierra Space’s Dream Chaser, the world’s first winged commercial space plane, is targeting a September launch to ferry cargo to the ISS as part of the company’s $3 billion contract with NASA.

Sierra’s second act will be an inflatable space habitat called LIFE (Large Integrated Flexible Environment). The first habitat measures 27 feet in diameter and rises to the equivalent of a three-story building.

Robb Report’s recent visit to the aerospace company’s headquarters and research facility in Louisville, Colorado, included an exclusive tour of its inflatable space habitat. The full-scale prototype is designed to launch into space inside a conventional rocket and then expand—while in orbit—into globular living quarters.

“Walking through it now might feel claustrophobic, but when you’re floating, it’s very roomy,” says Sierra Space’s chief safety officer Angie Wise. Above her is an upside-down hammock harnessed to the ceiling—“The astronauts have to strap in, or they’ll float around”—and beside it, a copy of sci-fi thriller Project Hail Mary by Andy Weir (who also wrote The Martian), nestled within its own perch like a makeshift nightstand.

This is where the next generation of astronauts and scientists will conduct research in microgravity, the ideal climate for developing technology varying from 3-D-printed human organs to battery chemistries that can increase the range of today’s electric vehicles tenfold, according to Sierra Space CEO Tom Vice.

“I think we’ll have the ability to disrupt any industrial company,” Vice says, standing in the center of a glass-walled observation room overlooking Sierra Space’s Mission Control Center. Vice and about a dozen of the company’s flight controllers plan to oversee Dream Chaser’s first space flight, on the back of a United Launch Alliance Vulcan Centaur rocket at Cape Canaveral’s spaceport in Florida.

At first, Dream Chaser will ferry cargo between Earth and the ISS. But the company says the spaceplane will eventually transport people such as astronauts, scientists, and researchers into low-Earth orbit—about 250 miles from Earth, where the ISS now lives—and host them aboard its LIFE habitat, a floating platform designed to allow humans to live and work comfortably for weeks in low-Earth orbit and beyond.

Wise ushers us into the house-sized, donut hole-shaped prototype looming over the factory floor at Sierra Space’s headquarters. Resembling something between a yurt and a hot air balloon, the structure’s outer casing is made with a high-strength matrix of “softgoods” materials that become rigid under pressure.

Fully inflated, it measures one-third the volume of the ISS, but Sierra Space is developing even larger LIFE modules. Its LIFE 5000, for example, expands to five thousand cubic meters (about 177,000 cubic feet) on orbit—bigger than the entire space station—in just one launch. The company is also partnering with Jeff Bezos’ Blue Origin to launch the first-ever commercial space station, a “mixed-use business park” called Orbital Reef, which it hopes to open by 2030. The plan is for future versions of the LIFE habitat to house a hotel, restaurant, and labs where researchers can experiment in microgravity.

This prototype on the factory floor can accommodate four to six people, with plenty of space for research laboratories and exercise equipment. The “top” floor will host a vegetable garden to provide crew members with a steady supply of fresh produce when they want a break from freeze-dried meals. “A lot of work goes into getting fresh food into space,” Wise says. “If we want to go to Mars eventually, we have to learn how to grow food.”

The thick matrix of materials encasing the dome is designed to withstand impact from micro-meteoroids and orbital debris, as well as to protect astronauts from internal pressure and space radiation. Its dominant material is Vectran, a chemically-woven fiber that’s five times stronger than steel when inflated in orbit and used in NASA’s spacesuits. The soft material can deflect the impact of meteors and other space debris better than titanium or Kevlar, like a “bulletproof space vest,” Wise says.

Using a woven pattern to link its nine layers of textiles, the matrix is robust enough to withstand a meteor shower but amply versatile for astronauts on board to repair holes in the surface by 3D-printing a patch of material.

To evaluate its durability, the prototype has undergone several “burst tests” at NASA’s Marshall Space Flight Center in Huntsville, Alabama, where it was inflated to see how much internal pressure it could bear before it explodes. In its most recent test, a full-scale prototype exceeded NASA’s recommended safety levels, lasting up to five times ambient pressure.

This latest burst test included a metallic window sub-structure—or blanking plate—as a stand-in for a window, an architectural feature especially crucial for longer journeys. The plate also serves to create a rigid point in a soft structure used for mounting robotic arms, antennae and other equipment. Wise says, “Astronauts love windows, because what’s the point of being up there if you can’t see out?”

Across the factory floor from the LIFE habitat prototype, engineers are at work building a second Dream Chaser spaceplane, called Reverence. Sierra wouldn’t release many details, but says it’s being developed for missions to the ISS, among other potential applications.

The first Dream Chaser spaceplane—called Tenacity—has been delivered to NASA’s Kennedy Space Center in Florida where it awaits its inaugural launch. Its sleek, white, and slightly birdlike silhouette measures 30 feet long with wings that stow for launch and enable the spaceplane to fit inside a conventional rocket fairing. Tenacity’s compact body and the 24-foot wingspan that deploys in orbit enable a key breakthrough: the ability to land horizontally on any commercial runway that can accommodate a Boeing 747 or Airbus A380.

When equipped with Sierra Space’s 15-foot Shooting Star module, Dream Chaser can carry up to 12,000 pounds of food, water, and supplies to the ISS. The module is designed to burn up upon reentry, creating the opportunity to dispose of up to 8,500 pounds of trash from the space station after each mission.

Tenacity’s first flight will mark a significant milestone toward fulfilling Sierra Space’s goal: to become the largest real estate developer in space, providing the transportation and the destination as well as the commercial economy that will power the Orbital Age—enabling humans to live and work in space on a permanent basis. Supplying the ISS is just the first step in Sierra’s aspirations for Dream Chaser to travel beyond low-Earth orbit, journeying to the moon and, eventually, into deep space.

The company plans to develop a crewed version of Dream Chaser that can bring astronauts, as well as cargo, to the ISS.

Meanwhile, on Earth, Sierra Space has signed agreements to start developing a global network of landing sites that includes the Space Shuttle landing strip at Kennedy Space Center in Florida, Huntsville Airport in Alabama, and New Mexico’s Spaceport America, as well as facilities in Oita, Japan, and Cornwall, England. The long-term goal is to land on commercial runways at airports worldwide, allowing Dream Chaser to deliver supplies or people to various places on Earth at a faster clip than conventional aircraft.  

“We want to work with companies that want to find answers to the world’s hardest problems,” says Vice. “That includes biotech companies thinking about next-generation drugs for oncology or longevity and semiconductor companies trying to figure out the new chip that lowers energy consumption.”