NASA’s Race to Replace the International Space Station: The Countdown to 2030

As NASA approaches a pivotal moment in its operations, the future of human activity in low-Earth orbit (LEO) hangs in the balance. The International Space Station (ISS), NASA's flagship orbital laboratory, is nearing the end of its operational life. The question looming large is whether the agency will be able to transition smoothly to a private space station, or face the possibility of a gap in human presence in orbit for the first time in decades. With NASA’s focus shifting toward deeper space exploration through its Artemis Program, which aims to return humans to the Moon and eventually reach Mars, LEO remains a critical frontier for scientific research and technological development.
As 2030 approaches, NASA is working on a plan to replace the ISS with one or more commercial space stations under its Commercial LEO Destinations (CLD) program. The next year will be decisive for determining the future of NASA’s presence in LEO, with contracts set to be awarded to private companies for the development of new space stations. But with this transition comes uncertainty. Can these companies meet the demanding requirements, and more importantly, is there a strong enough business case for them to succeed?

The Need for Continued Microgravity Research
Despite the allure of deep space exploration, NASA officials, including Deputy Administrator Pam Melroy, stress the ongoing importance of LEO for scientific research. Microgravity research aboard the ISS has already delivered critical insights into how long-duration spaceflight impacts human health—a crucial area of study for missions to Mars and beyond.
“We are so not done with research in microgravity,” Melroy said. “We’ve gotten ourselves to the point where we kind of understand the risks of a one-year duration mission in space, but we’re going to have to keep pressing on that because we really have to get our arms around mitigations and solutions for what will likely be a two- or three-year trip to Mars.”
In addition to human health, NASA’s technological advancements in life support systems (ECLSS) have pushed efficiency rates close to 97% for recycling water and air aboard the ISS. But long-duration missions to Mars will require systems with nearly 100% efficiency—a daunting challenge that can only be refined with continued research in LEO.
To formalize its low-Earth orbit research and development strategy, NASA has published a draft version of its “Microgravity Strategy,” which outlines the space agency’s goals for the 2030s and beyond. The final version of this document, due by the end of 2024, will shape NASA’s needs for future space stations and set the stage for the next phase of the CLD program.

Commercial Space Stations: A High-Stakes Gamble
Three years ago, NASA awarded preliminary contracts to companies like Blue Origin, Nanoracks, and Northrop Grumman to begin the development of commercial space stations. A fourth company, Axiom Space, received similar funding a year earlier. However, the road ahead has been rocky. Northrop Grumman pulled out of the race due to financial concerns, leaving only Axiom, Blue Origin, and Voyager Space (which acquired Nanoracks) as serious contenders.
While NASA would like to award two contracts in the next phase to foster competition, there are no sure bets among the current candidates. Axiom, once considered a frontrunner, is facing severe financial challenges, while Blue Origin seems less committed to the program, potentially waiting to see how much funding is available in the next phase. Voyager Space has shown promise but remains largely untested in such a complex endeavor. There is also speculation that SpaceX, with its revolutionary Starship vehicle, might enter the race, but CLD is not currently a priority for the company.
As the clock ticks down to the retirement of the ISS, NASA is asking commercial providers to deliver at least a "minimum viable product" by 2030. Melroy acknowledges that the journey to fully functional commercial space stations will likely be phased, with basic operations starting before more ambitious goals can be realized.

Congressional Support and Funding Challenges

Funding for NASA's CLD program has been inconsistent, raising questions about whether the space agency and Congress truly prioritize maintaining a presence in LEO. While funding levels have increased in recent years, they remain a fraction of what will be needed to build and sustain new commercial space stations. According to data from The Planetary Society, CLD has received just $650 million in funding since 2019—a small amount compared to the billions required to construct and operate orbital habitats.
The lack of clear commitment from NASA and Congress is a major concern for the private companies involved in the CLD program. Commercial space stations require significant capital investments, and without assurance that NASA will remain an anchor customer, it is difficult for companies to secure the funding they need to proceed.

What If There’s a Gap?
As NASA moves closer to deorbiting the ISS, which is scheduled to occur in 2030, the possibility of a gap in human presence in LEO becomes more likely. While NASA officials have expressed a desire to avoid this, some suggest that a temporary gap may not be catastrophic. Phil McAlister, a key figure in NASA’s commercial space efforts, stated that although a gap would be unfortunate, it wouldn’t be "unrecoverable." In the event of a gap, NASA could rely on vehicles like SpaceX’s Crew Dragon to conduct limited research and maintain a presence in space until new space stations come online.

The Market Dilemma
Beyond NASA and government-funded missions, it remains unclear whether there is enough commercial demand to support private space stations. A 2017 report raised doubts about the profitability of human spaceflight for non-governmental purposes. While space tourism, pharmaceutical research, and other industries have shown interest, none of these have yet emerged as the “killer app” that could make private space stations viable.
Automated manufacturing, such as Varda’s pharmaceutical research missions, may further reduce the need for human activity in space, potentially undermining the business case for private stations. Moreover, SpaceX’s Starship, with its potential for short-duration orbital flights, could offer a more cost-effective alternative for space tourists.

The Path Forward
NASA’s push for commercial space stations represents a bold experiment in privatizing low-Earth orbit. The success of this effort will depend not only on the ability of private companies to meet NASA’s requirements but also on the broader market demand for human space activity. For now, NASA’s commitment remains uncertain, and time is running out. With the ISS nearing the end of its life, the coming year will be critical for determining whether NASA can maintain a presence in LEO—or face the prospect of being left behind in the race for space.
As 2030 approaches, the future of NASA’s operations in low-Earth orbit remains a high-stakes gamble, with the outcome still far from certain.