Five Britons have been shortlisted for a controversial space project to establish a permanent settlement on Mars.
The candidates have been chosen from more than 200,000 applicants for the privately-funded one-way mission due to blast off in 2024.
The project is being organised by Dutch entrepreneur Bars Lansdorp who claims the citizen astronauts will grow their own food and be protected from radiation by a "hollow water tank".
A rover will first be deployed on the planet in 2020 to chose a location where the soil contains enough water and there is enough sunlight to power the settlement.
Mr Lansdorp said: "The brightest young minds of our planet are being invited to participate in Mars One's first Mars lander. We do this to inspire students to believe that anything is possible."
But suspicious critics believe the mission is a publicity stunt to raise revenue for a reality television series produced by Big Brother producer Endemol.
Australian journalist Elmo Keep told Sky News: "200,000 people did not apply; 2,071 paid the registration fee.
"According to the dozens of people I interviewed over the course of a year for the story, there is scant-to-no proof Mars One has any capability to make it real."
A Mars One statement released earlier said: "Endemol-owned Darlow Smithson Productions (DSP) will exclusively follow the selection and training of the world's first one day astronauts to Mars."
But a DSP spokesperson told Sky News they had pulled out of the project after failing to reach agreement on the details of the contract.
Research carried out at the Massachusetts Institute of Technology suggests a manned mission to Mars would see the crew die within 68 days.
But Hannah Earnshaw, a 23-year-old astronomy student at Durham University, is among the Britons on the shortlist and said the trip was "really appealing".
"My family is pretty thrilled. They're really happy for me," she said. "Obviously it's going to be challenging, leaving Earth and not coming back.
"I've had support from my friends and family and we can still communicate via the internet."
Ms Earnshaw said she was "not surprised" there was scepticism about the project which she said was "definitely feasible".
But International Space Station Commander Chris Hadfield said candidates would be disappointed.
Speaking to US magazine Matter he said: "There's a great self-defeating optimism in the way this project has been set up.
"I fear it's going to be a little disillusioning for people because it's presented as if it's going to happen and so all those people are excited."
Challenged over the likelihood of the project getting off the ground, in 2012 Mr Lansdorp rejected claims the mission was a stunt.
"If you look at the team involved in Mars One, none of us would do this as a hoax," he said.
Mars One were unavailable for comment when contacted by Sky News.
