Kiwi scientist Sarah Kessans' astronaut dream moves a giant leap closer

Aspiring astronaut Dr Sarah Kessans says it was "humbling just to be amongst" staff at a Nasa training centre in Texas.

A New Zealand scientist is a giant leap closer to realising her dream of becoming a Nasa astronaut after a week of testing for the 2017 intake.

Dr Sarah Kessans, a postdoctoral fellow at the University of Canterbury, was one of 120 candidates invited to Nasa's Johnson Space Centre in Houston, Texas for a week last month.

From that group, the top 1 per cent of shortlisted applicants, 50 will be invited for final interviews. Between eight and 14 people will be chosen as Nasa's 22nd Astronaut Candidate Class, reporting for duty next August.

The 33-year-old said she couldn't disclose the details of what she did during the visit but that there were "lots of medical and psychological testing, a formal hour-long interview, and tours of many of the facilities there".

Kessans said everyone there was "exceptionally passionate, intelligent, and just really fun".

"Everyone there understands that they are a part of something bigger than themselves: part of a massive, inspiring undertaking responsible for exploring our universe, pushing science forward, and really connecting humanity on a global scale. It was humbling to just be amongst it."

Kessans, from the university's Biomolecular Interaction Centre, said there was time to interact with current members of the Astronaut Corps.

"Watching videos of them float through the International Space Station or seeing pictures of them all over the media makes them seem superhuman, but when you're talking with them as they try to figure out a broken printer, you realise that they have the same hopes, dreams, and frustrations as we all do.

"Getting to interact with them as they went about their - albeit pretty fascinating - normal daily activities made the possibility of actually joining their ranks seem more achievable."

Nasa used the week - described by Kessans as the best of her life so far - to analyse the candidates through tests and activity based team challenges.

One of the many highlights was the chance to experience a simulated ascent in the new Orion capsule - a Nasa exploration vehicle designed to take humans further into space than ever before.

"I could not believe my luck when one of my fellow interviewees and I were invited to lie down on our backs in the Orion seats ... As we were rolled back into the launch/landing positions, with our knees tucked up towards our chests, the control panels in front of our faces, and the windows of the module behind us, we could not hide our massive grins.

"During the simulation, we were able to see plasma through the windows as the craft re-entered the atmosphere, watch as the parachutes opened, and feel the splash of the capsule as it hit the ocean.

"The experience allowed us to reflect on our own potential trips to space, and it made the journey - with all of its risks and rewards - seem that much more real."

Kessans said her fellow interviewees were from a range of backgrounds but shared a passion for space exploration and life in general.

The biggest challenge was knowing that only 10 per cent would make the intake.

Whatever the outcome, Kessans has already had plenty of adventure, including spending 16 hours clinging to a capsized rowing boat in the Atlantic Ocean during a 4800km race in 2006 and setting a world record for rowing across the same ocean in 2008.

She will find out in December if she's made the next stage of the Nasa selection process.