NASA fears gap in astronaut crew at multibillion-dollar space station

ORLANDO, Fla., Feb. 16 (UPI) -- Having spent well over $150 billion on the International Space Station, NASA fears a potential lack of launch vehicles could leave the orbiting platform without a U.S. astronaut and create a potential safety risk.

Such a gap would occur only if a crew had a problem that forced them to leave the space station early, but it would represent a costly "lost opportunity that cannot be regained" for maintenance work and science, NASA spokesman Josh Finch said in an email.

"NASA's position is that at least one U.S. crew member on the International Space Station at all times is the best way to maintain safe operations," Finch said.

To resolve the potential for a gap, NASA is considering buying an additional seat on a Russian Soyuz rocket and capsule planned for launch in the spring, he said.

NASA has sent six astronauts to the space station aboard SpaceX's Dragon capsules, four of whom are currently in orbit as SpaceX Crew 1. A launch of SpaceX Crew 2 is planned April 20, but the feared gap could occur in the six months after that, according to Finch.

SpaceX Crew 2 will launch four astronauts -- two U.S. crew and one each from Japan and the European Space Agency -- who would briefly join the four members of Crew 1 before they depart in late April or early May.

Having multiple U.S. astronauts on board the space station is desirable because they can perform more science and maintenance and help each other on spacewalks.

But the extra launch seat would create a contingency plan in case a problem forces some crew members to depart early, Finch said.

NASA pursues a policy of "dissimilar redundancy" for such flights, meaning the agency always wants a backup launch available in case of a medical emergency or mechanical failure, he said.

The potential gap at the space station comes as the Boeing Co. continues to test its Starliner capsule, which originally was to be operational years ago.

Boeing's test flight in December 2019 failed to reach the space station, but landed safely. The company plans another test flight March 29. If that test flight is successful, NASA could move to certify Starliner for regular crewed flights, but that process can take several months.

Before SpaceX's successful Demo 2 flight in May, NASA had relied only on Soyuz capsules launched from Kazakhstan -- at $70 million to $80 million per seat -- since the space shuttle era ended in 2011.

In the later years of the shuttle era, NASA usually had a backup shuttle prepared to launch relatively quickly in event of a problem, and the agency has had similar contingency plans with Russia's Soyuz program. But NASA's goal is to no longer purchase seats on Soyuz missions after this year.

SpaceX and Boeing are part of NASA's Commercial Crew Program, which was designed to have two private companies providing launch services -- so that the space agency would have options and backups. That strategy precludes NASA from relying exclusively on SpaceX for launches.

Two Russian cosmonauts normally are on board the orbiting platform, but even they require a counterpart from the United States or another nation to help with spacewalks.

NASA has some limited ability to run equipment on the space station remotely from the ground, and even has flying robots called Astrobees on board.

But those wouldn't function properly without astronauts, said Abhishek Cauligi, a doctoral candidate in aeronautics who works at Stanford University's Autonomous Systems Laboratory in California.

"Conducting science on board the ISS without any human supervision is currently out of reach, in part due to the fact that the ISS wasn't designed with this in mind," although future space stations may have more robotic capability, Cauligi said.

He has worked on science related to the Astrobees and other robotic systems on the International Space Station. Cauligi noted that crew arrivals also carry cargo and new science equipment.

"Research projects and experiments on the ISS are typically scheduled months, if not years, in advance, so delays ... could affect many projects," he said.