BOSTON — As NASA takes steps to make it easier for researchers and companies to use the International Space Station, some of those potential users want more guidance about how long the station will be around and what might replace it.

“When is ISS going to end? When will it terminate? We don’t know, and that’s a problem,” said John Shannon, Boeing vice president and program manager for NASA’s Space Launch System exploration-class rocket, in a presentation at the ISS Research and Development Conference here July 8.

In early 2014, NASA announced it planned to extend operations of the ISS from 2020 through at least 2024. Since then, the governments of Russia and Canada have endorsed that extension, but the other two major partners, Europe and Japan, have yet to decide on whether to participate.

John Shannon. Credit: NASA, Bill Ingalls
John Shannon. Credit: NASA, Bill Ingalls

Shannon, who formerly managed Boeing’s space station work, argued there is a second, earlier termination date for the station, when researchers decide that they will not have enough time to develop experiments to fly there before station operations end. “That date is probably three to four years before termination,” he said. “It’s very good we have 2024 in the mix, but I don’t think it’s enough.”

One of the station’s biggest commercial users agreed. “The cutoff is not 2024. The cutoff will be sometime sooner,” said Jeff Manber, managing director of NanoRacks. “We already had a client who asked us, ‘Why should I invest tens of millions of dollars in the ISS if it’s only going to be around to 2024?’”

Their concern is that if there was no plan for a new facility to succeed the ISS for such research by the time of that research cutoff, the growing interest in space research could be wiped out. “Once we know we’re done with the station, it’s too late,” Manber said. “You have to anticipate and you have to be ready.”

Manber said he wanted a commercial space station in place before the ISS ends, providing an overlap and a transition path for customers currently using the ISS. NASA officials have indicated in recent months that the agency has no plans to develop a replacement space station once the ISS ends, although it could be a customer of a commercial facility.

An alternative approach other conference panelists suggested is to continue operating the station beyond 2024 or even 2028, the date NASA has stated the station could operate from a technical point of view. “I think the station was built to last,” said Frank Culbertson, president of the space systems group at Orbital ATK and a former astronaut. “I do think we should plan on station going as long as we can safely fly it.”

He argued against setting a specific date for ending the station. “This program has so much invested in it and so many users now that I think it would be counterproductive to put an end date on it at this point,” he said. “Until we have an alternative, and until commercial investment grows in another facility or a joint facility, I think you need to continue to assume that it’s going to go on as long as you can keep it safe.”

Manber, though, argued that an end date is needed in order to drive commercial investment decisions. “How do I get my investment money if there’s no end date?” he asked. “That’s the problem.”

The debate about the future of the ISS and its successor comes as NASA is making new efforts to streamline space station procedures to make it easier for people to fly experiments. That includes giving researchers more flexibility to develop investigations for the ISS, and allowing them to take more risk provided it does not jeopardize safety.

“It’s up to researcher to decide how much risk do you want to take, how quickly do you want to get to orbit,” said Marybeth Edeen, manager of the ISS Research Integration Office, in a July 8 presentation at the conference. “It is a huge shift in how we think, and it is a very difficult mindset change within the program.”

That shift in mindset is not enough, some warned, if there is no long-term planning on the future of the ISS. “It was a mistake to retire the shuttle before we had a domestic capability to launch our astronauts,” said Shannon, who earlier in his career was shuttle program manager at NASA. “Likewise, I think it’s a huge mistake to end the station before we have a capability in place to continue that low Earth orbit research.”

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...