WASHINGTON — Axiom Space, a company with ambitions to develop a private space station, announced March 5 that it has signed a contract with SpaceX for a commercial Crew Dragon mission to the International Space Station.

Axiom said the mission, scheduled for launch no earlier than the second half of 2021, will carry one Axiom professional astronaut and three private astronauts to the ISS. The mission will last 10 days, including eight at the station and two in transit. The company did not disclose terms of the deal, nor pricing for the individual private astronauts.

In a statement, Michael Suffredini, chief executive of Axiom, called the flight a “watershed moment” for commercialization of low Earth orbit. “This will be just the first of many missions to ISS to be completely crewed and managed by Axiom Space, a first for a commercial entity,” he said. “Procuring the transportation marks significant progress toward that goal, and we’re glad to be working with SpaceX in this effort.”

The flight represents the start of Axiom’s long-term plans. The company anticipates doing as many as two such missions a year in accordance with NASA’s LEO commercialization strategy announced last June, which allows for private flights and short-term stays by commercial spaceflight participants.

NASA selected Axiom Jan. 27 to gain access to a docking port on the station’s Harmony, or Node 2, module. Axiom plans to attach a commercial module to that port in late 2024, which will be equipped with docking ports and an “Earth Observatory,” a larger version of the station’s cupola.

“That module looks like a node,” Suffredini said in an interview shortly after the NASA award in January, describing it as being similar to the station’s existing Node 2 and Node 3 modules, but one to two meters longer.

That will be followed in 2025 by a habitation module and, in 2026, a research and manufacturing module, both of which will be attached to that initial module. Ultimately, that “Axiom segment” of the station will detach when the ISS is retired and, with the addition of a power and thermal module, became a free-flying space station.

Private astronaut flights to the ISS, though, are the first steps in that effort. The company stated that it was in discussions with NASA “to establish additional enabling agreements for the private astronaut missions to ISS,” which a company spokesperson said involves the specifics of fitting a private mission into the overall schedule of missions going to the station.

The flight announcement comes as Axiom works to raise outside investment. Suffredini said in that earlier interview that the company is in the process of raising a Series A funding round on the order of $100 million, which it hopes to close by the beginning of summer.

The contract is the second deal for a commercial Crew Dragon mission announced in less than a month. Space Adventures announced Feb. 18 it had an agreement for a Crew Dragon mission launching between late 2021 and the middle of 2022. That flight, carrying four private astronauts, will not go to the ISS but instead fly in an orbit more than twice as high as the station.

“Thanks to Axiom and their support from NASA, privately crewed missions will have unprecedented access to the space station, furthering the commercialization of space and helping usher in a new era of human exploration,” SpaceX President Gwynne Shotwell said in the Axiom statement.