WASHINGTON — A proposed commercial space station has passed a key early NASA review, allowing it to move into the next phase of its design.

Blue Origin and Sierra Space, the lead partners on the Orbital Reef station, said Aug. 22 that the station passed a system definition review (SDR) with NASA. The review is part of a Commercial Low Earth Orbit Destinations, or CLD, award they received from the agency last December to mature the design of Orbital Reef.

The review, conducted between mid-June and mid-July, was intended to confirm that the Orbital Reef concept met various functional and performance requirements. Passing the review allows the companies to further develop the overall design of the space station.

“This SDR moves Orbital Reef forward,” said Brent Sherwood, senior vice president for advanced development programs at Blue Origin, in a statement. “We are meeting the needs of both the commercial marketplace and NASA’s requirements.”

The companies unveiled Orbital Reef last October as part of a team of companies and organizations that includes Boeing, Redwire and Arizona State University. The modular station, designed to expand to accommodate additional users, can support research and industrial applications as well as tourism.

“The microgravity factories and services provided by Orbital Reef have the potential to revolutionize every industry and become a major growth contributor to the U.S. and world economies,” Tom Vice, chief executive of Sierra Space, said in a statement.

Orbital Reef is one of three proposed commercial space stations that received funded Space Act Agreements from NASA in December as part of the CLD program. Besides the $130 million for Orbital Reef, a team led by Nanoracks won $160 million for its Starlab station while Northrop Grumman received $125 million for its own commercial space station concept. A fourth company, Axiom Space, has a separate agreement with NASA to attach commercial modules to the International Space Station that will later form the core of a commercial space station.

NASA is supporting initial development of these designs as part of its long-term plans to transition from the ISS to commercial stations by the end of the decade. However, the agency has faced criticism from its own safety advisers as well as its inspector general, who cautioned that commercial stations may not be ready by the end of the decade.

At the ISS Research and Development Conference last month, both NASA officials and representatives of the four companies working with the agency rejected those concerns. The companies argued that they believe their commercial stations will be ready by late this decade, enabling a gradual transition from the ISS by the end of the decade.

Janet Kavandi, president of Sierra Space, said on that panel that current plans for Orbital Reef called for having the first modules launched in 2027, a schedule she said provides plenty of time to transition from the ISS. “We are well on our way.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...