Shocking amount of time it could take ‘stranded’ NASA astronauts to recover from nine-month stay in space

After NASA astronauts Sunita Williams and Butch Wilmore finally landed home earlier this week to a heroes’ welcome, many people have been curious to know what the aftermath of space travel entails.

After all, it’s no small feat travelling out to the International Space Station, let alone spending a casual nine months there.

The pair’s mission was only supposed to last around a week, but their trip was unexpectedly extended when technical issues hampered things.

Thankfully, they can now be reunited with loved ones at home, and start returning to their normal lives.

But just how long does that adjustment take?

While only around 700 people have been to space, data is naturally fairly thin on the ground.

However, there’s a lot we know from astronauts who have previously visited, and have had to reacclimatise to Earth.

Sunita Williams after arriving back to Earth (NASA / Keegan Barber / Handout/Anadolu via Getty Images)

Upon immediately landing, there’s a risk of dizziness and nausea from the journey home - hence the stretchers Williams and Wilmore were placed on, as part of NASA protocol – which can take at least two or three days to settle, according to astronaut Tim Peake.

But there are other aspects that may take much longer to resolve, including muscle and bone loss.

A 2022 study documenting the latter in 17 ISS astronauts in missions that averaged five-and-a-half months found that, a year after returning, they exhibited on average 2.1 percent reduced bone density of the lower leg and 1.3 percent reduced bone strength.

Helen Sharman, who was the first Briton in space, told the BBC: "It will probably take them a few months to build up their muscle mass."

But she said bone mass could take ‘a couple of years’ until it recovers – and even then, there are often ‘subtle changes in the type of bone that we do rebuild after returning to Earth that may never return to completely normal’.

Williams and Wilmore last April before they set off (Instagram/@nasaastronauts)

Some people also face lasting eyesight impairment due to the way microgravity affects the eyes in space – a condition known as Spaceflight-Associated Neuro-Ocular Syndrome (SANS).

In general, NASA astronaut Frank Rubio, who returned from space in 2023 after 371 days away from Earth, told Time Magazine the adjustment to arriving home takes much longer than acclimatising to space.

He explained: "The first two or three months after your return is really focused on [recovery], just kind of reincorporating yourself into Earth, your family, and then also rehabilitating your body.

"You adapt incredibly quickly to being in space, but then unfortunately, the readaptation process back to earth can sometimes be a little bit longer and more difficult.

"And that's just, I think, because the forces of gravity and the forces at play here on Earth tend to have a stronger effect on your body.”

Of course, there’s also the psychological effects of space travel, which will obviously vary person-to-person.