Experts reveal what the International Space Station smells like and it's not what you'd expect

A bunch of experts have revealed exactly what the International Space Station smells like ahead of the two 'stranded' astronauts returning home.

Barry 'Butch' Wilmore and Sunita 'Suni' Williams have been up on the ISS for nine months and while it has been unfortunate for them, it has invigorated curiosity around space.

And while many may be aware of the overview effect, an emotional experience reported by astronauts after getting a sense of awe from seeing Earth from space, most of us probably aren’t familiar with what it smells like.

When it comes to the International Space Station, what your eyes can see tends to be the focal point but what about what you smell while you stare at the Earth from a window hundreds of miles away?

Alan Duffy, an astrophysicist at Swinburne University, has explained what it's actually like, and it doesn’t sound pleasant.

The astronauts 'stranded' onboard the ISS have got a lot of people asking questions about space (YouTube/NASA Video)

As per The Guardian, he said: “Fluids build up in their heads, to they feel like they have a constant cold.

“[Your sense of smell is diminished] which is probably a good thing, by the way, because it reeks up there.”

And the astronauts that have been lucky enough to be among the 270 people to visit the ISS haven’t had the best things to say about how it smells up there.

It's not like they can exactly open a window if things get a little musky...

Speaking to Wired Magazine, American NASA astronaut Scott Kelly painted quite a picture of its unique aroma.

He said: “I was touring the Harris County Jail [in Texas], and there’s this room that smells like space station - combination of antiseptic, garbage, and body odor.”

Smells tend to linger a little while longer without gravity (NASA via Getty Images)

But to make matters worse, Kelly said that due to the absence of gravity, bodily smells... well, they tend to linger around. Grim.

Other astronauts have admitted that describing the smell is a little difficult, which makes sense since how often do these odd smells really mix on Earth.

UK astronaut Tim Peake previously said the ISS smells ‘like a barbecue that’s gone wrong’ and Italian astronaut Samantha Cristoforetti simply said it was a ‘peculiar odor’ she had to adjust to.

However, Peak appeared to be less bothered by the smell than some of the other astronauts as he also said it smells ‘like static electricity’.

Well, better than 10-year-old farts and burps from space food, I guess.