ESA astronaut on the difference between flying in a Soyuz and piloting a Crew Dragon

Plus: We chat about going to the Moon and keeping the ISS running for a few more years

Interview The first Dane to fly in space, Andreas Mogensen, thinks there's every chance the International Space Station (ISS) might last for a few more years and harbors hopes of visiting the Moon.

Mogensen, one of ESA's veteran astronauts, was the first non-US pilot of a SpaceX Crew Dragon. His first mission to the ISS was aboard a Soyuz, and the two craft represent quite different eras in spaceflight. The Register wondered, from an astronaut's perspective, how they differed.

"The Soyuz is a fascinating spacecraft," he tells us, "It was developed in the '60s and has been in use ever since then, so it's very reliable, very robust.

"The version we flew in 2015 still had the entire analog layer at the bottom, which means that you could lose the electronics – the digital system – and still go back and use the analog layer. You have two hand controllers that are directly connected with the spacecraft thrusters, you have the periscope like on a submarine, there are a lot of valves, a lot of manual buttons – things that you can turn, things that you can push."

And the Crew Dragon? "Like a modern Tesla."

"It has three touch screens, and almost everything is implemented in software. There is a minimal number of actual physical buttons you can push… but it's also a lot bigger and much more comfortable to sit in." Unlike the almost fetal position required by the Soyuz, The Reg would imagine.

The two are both highly automated, however. Mogensen explains that the pilot's role is to keep an eye on the spacecraft and be ready to immediately take over if required.

Regarding the troubled third crew transportation system, Boeing's Starliner, Mogensen says, "It shows that the system worked. NASA reviewed the data and determined that the safest action was not to return them [the crew] home."

The Starliner's first crewed mission was launched to the ISS earlier this year. However, after several issues, most notably with the spacecraft's thrusters, managers elected to return the Starliner empty and use a SpaceX Crew Dragon to bring the astronauts back in 2025.

"I don't think most astronauts are concerned about the fact that Starliner was launched because it's still a developmental program. This was a test flight, and sometimes, you discover things during the test flight that you didn't think were a problem.

"So when they discovered what had occurred, they reviewed the data, and they took the necessary steps to ensure the safety of the crew."

And the impact of another Starliner delay? Mogensen reckons it will be minimal – SpaceX was launching crews before the Starliner mission, "hopefully they'll just be able to continue…"

Keeping the ISS lights on for a little longer

The ISS is due for retirement. Currently NASA and ESA reckon the end will come in 2030, although Russia has yet to formally commit past 2028. Mogensen, who has two spaceflights and one tour of the ISS under his belt, reckons there's a chance the lab will endure into the next decade.

"I wouldn't be surprised if we extended it a few years," he says.

Even with the air leaks?

"From an astronaut's point of view, I don't think it's a problem. So long as we understand the leaks and have a plan for dealing with them. At the moment, you know, we're trying to understand exactly what causes them, what causes them to grow..."

There's also the possibility of sealing off the affected section. A recent NASA report [PDF] listed leaks in the Service Module Transfer Tunnel, which connects the Russian Zvezda Service Module to the rest of the ISS. The ISS crew routinely keeps the hatch to the tunnel closed when it is not in use, but sealing it permanently would mean one less docking port.

"The lucky point is that the cracks are confined to that chamber at the very end. So, as long as Russia is willing to forego that docking port, that wouldn't impact operations too badly," says Mogensen.

"So, yeah, worst case, you could seal it off, and I think the Space Station could continue. But of course, you never know what other problems might arise."

Not that Mogensen would have to deal with them. Having flown two missions, he is unlikely to pay the ISS another visit. "ESA has told us that the coming missions to the ISS will be reserved for the new team, and that if any lunar missions arise it'll be for our class." ®