What happens next to ‘stranded’ NASA astronauts after they land safely back on Earth

Sunita 'Suni' Williams and Barry 'Butch' Wilmore landed back on Earth on Tuesday evening (18 March), where they splashed down off the coast of Florida.

The pair have been stuck up on the International Space Station (ISS) for nine months after setting off on an eight-day mission last June.

Due to technical faults with their Boeing Starliner - specifically helium leaks and a thruster malfunction - the pair had to watch the Starliner return to Earth without them after it was deemed too unsafe to travel.

They've been patiently waiting for an alternative ever since, and on Tuesday - thanks to a NASA's SpaceX Crew-9 mission - the pair returned to Earth to be reunited with their loved ones.

As the capsule splashed down onto Earth, dolphins could be seen swimming nearby as teams worked to remove the spacecraft from the water.

Ahead of readjusting to their normal every day lives on Earth, it's expected that the astronauts will have to go through some protocol, as well as health checks, after so long in space.

A NASA spokesperson has previously said: "All NASA astronauts aboard the International Space Station undergo routine medical evaluations, have dedicated flight surgeons monitoring them, and are in good health."

Once they returned to Earth, Williams and Wilmore could be seen smiling for the cameras as they were transported from the capsule and on to stretchers.

"A lot of them don't want to be brought out on a stretcher, but they're told they have to be," John DeWitt, former senior scientist at NASA's Johnson Space Center told LiveScience.

The astronauts splashed down on Tuesday evening (18 March) (Keegan Barber/NASA via Getty Images)

This is for a number of reasons, mainly because astronauts can struggle to walk after so long in space and need some time to adjust to Earth's atmosphere.

They can also experience dizziness and nausea when they travel home, similar to how some suffer motion sickness on a roller coaster or boat.

Our bodies are hard-wired to take advantage of gravity, but that obviously becomes difficult in a space habitat like the ISS and means astronauts are forced to adapt to an entirely new environment.

The pair have been on the ISS for nine months (NASA)

It's believed the astronauts will now be flown to NASA's Johnson Space Center in Houston where they will spend days having health checks.

They will then be signed off and able to go and spend time with their loved ones, who they won't have seen since June last year.