The Inspiration Mars team have said that the ideal crew for the mission will be, "two professional crew members - one man, one woman - flying as private US citizens."
Jane Poynter added that the crew members they sought should be a 'proven couple,' to help cope with the long trip.
The website for the mission added that, "method of crew selection and specific criteria to be announced at a later date."
More top news
Delivery company Deliveroo insists the majority of its riders are happy, as an ITV News investigation reveals the hardship of life for many.
Bavaria is set to roll out a ban of the full-face veil in a number of public places, including schools and universities.
A man who used a pickaxe and sledgehammer to ruin Donald Trump's Hollywood Walk of Fame star has avoided jail.