Wearing diapers in space

Director Ridley Scott's new movie The Martian is the latest attempt by Hollywood to imagine and re-create the wonders of space travel.

But while the film is a love letter to science, its story - about an astronaut left for dead by his crew after a freak accident on the surface of Mars - leaves out one crucial detail many other space movies have glossed over as well: astronauts wear adult diapers.

This unglamorous fact is pointed out almost apologetically by one of the consultants on the movie, Tracy Caldwell Dyson, the American astronaut who worked with stars Matt Damon and Jessica Chastain to get all the technical details right.

One of those details is that astronauts normally wear diapers under their space suits during long operations such as space walks.

Chastain, 38, worked closely with Dyson, 46, and also spoke to other experts at Nasa. When she asked them what annoyed them most about space movies, she says they had the same answer: It was about the diaper. "No one looks glamorous coming out of a space suit.''

Dyson, who has completed three space walks, was part of an expedition to the International Space Station in 2010 and flew on the space shuttle Endeavour in 2007. She says the 1983 movie The Right Stuff and 1995's Apollo 13 have been the most realistic cinematic depictions of what astronauts really do.

"What I love about Apollo 13 is that it tells the story of what Nasa does best and that is when it deals with something going wrong that we didn't plan for and how everyone comes together with all their ingenuity.

"People work their best, surprisingly, when stakes are high, and it's a testament to how much people care about one another too."

She says The Martian, based on the 2011 Andy Weir novel of the same name, captures this by showing how the crewmates and colleagues of stranded astronaut Mark Watney (Damon) do everything they can to bring him back to Earth.

"Both the movie and the book are about people striving to take care of people - that's exactly what is enhanced when it's Nasa doing this sort of thing."

Dyson, who is also an accomplished researcher and scientist, says another aspect of space travel that is hard to reproduce on screen is the effect of the very low gravitational pull.

"That's the weird one. It's really hard to bring that home to folks," she says, noting the indescribable sensation of one's organs and internal fluids floating in space.

"They float to your face and that's why when you see people in space they look puffy - it's because of the fluid shift.

"It's also why people have what we call 'space motion sickness', the same kind you get on a rollercoaster, but more prolonged.

"When you're in space, everything floats, including the fluid in your inner ear, and that sends a mixed signal to your brain because you see everything the right side up."

According to her, Nasa is "definitely making strides" towards an eventual manned mission to Mars, which the space agency recently confirmed has liquid water flowing on its surface, holding the possibility that the planet could sustain life.

"Nasa just went to work on building a rocket system that would take us to a destination in deeper space. We're also sending probes to Mars and taking snapshots of the places that Mark Watney visits in the book.

"So all the work we're doing on the space station and all scientific experiments in human research and technology have a bent towards what it's going to take to get us to Mars and be productive and healthy there," she says.

"And also be able to come back, of course."

Alison de Souza

A version of this article appeared in the print edition of The Straits Times on September 30, 2015, with the headline 'Wearing diapers in space'. Print Edition | Subscribe