ISS experiment
NASA astronaut Serena Auñón-Chancellor works on an experiment on the International Space Station. With only three people on the station for at least several weeks, research time will be limited. Credit: NASA

LAS CRUCES, N.M. — With the International Space Station likely to have only a three-person crew for an extended period, researchers expect there will be less time devoted to research.

The Oct. 11 failure of a Soyuz rocket two minutes after launch, forcing the Soyuz MS-10 spacecraft to abort and make an emergency landing, leaves the station with a three-person crew: commander Alexander Gerst of ESA, Serena Auñón-Chancellor of NASA and Sergey Prokopyev of Roscosmos.

While no decisions have been made about when the Soyuz rocket will be able to resume crewed launches, most involved with the station program expect the station’s crew to remain at three at least until December.

For NASA, that means that only Auñón-Chancellor and Gerst will be available to perform experiments on the station’s U.S. segment. There are usually three astronauts available to work on the U.S. segment, although for a time there were four, as NASA took advantage a Russian decision to temporarily reduce the size of its crew from three to two.

That had boosted the number of crew hours available to perform station research. “Utilization over the last [station] increment was slightly higher than expected,” said former astronaut Susan Helms, a member of NASA’s Aerospace Safety Advisory Panel, during a meeting of the independent safety group Oct. 11 at NASA’s Johnson Space Center.

Helms acknowledged at that meeting, just hours after the accident, that schedules for future research on the station will have to revisited. “That is now up for replanning, obviously, because it was dependent on five crew members being on board and what those crew members would do,” she said.

One of the biggest users of the ISS is NanoRacks, the company that provides commercial access to the ISS for internal experiments and satellite launches. The company has flown to date 700 payloads from 32 nations to the station, said Mike Lewis, chief technology officer of NanoRacks, during an Oct. 11 presentation at the International Symposium for Personal and Commercial Spaceflight here.

Having only three people on the station will affect the ability to carry out those experiments, he said. “We rely heavily on the crew,” he said. “We’re very aware that a lot of our experiments, and those of other payload developers, may have to be reevaluated.”

Many others, though, should be able to proceed as planned since they can be controlled remotely. “We’ve done a lot of work recently towards automation, and making things so that we can control them from the ground,” he said. Those experiments can be run from a control room at a NanoRacks facility in Houston.

“A lot of our experiments won’t be affected by a reduced crew,” he said. The split between human-tended and automated payloads, he said, was roughly half.

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...