Around 40 volunteers from thousands who applied for a one-way ticket to Mars gathered in the US capital Saturday to hear from the man behind plans to colonize the Red Planet.

Bas Lansdorp, a Dutch entrepreneur, plans to establish a permanent base on Mars in a mission he hopes will take off in 2022 if he can find the necessary $6 billion.

Would-be travellers on the mission -- named Mars One -- would never return to Earth.

"There's no return mission," Mars One chief Lansdorp said at George Washington University.

"That sounds very dramatic, but don't forget that in the history of our planet, people have always been going places, saying goodbye to their families for ever, and going there and living there.

"It's just part of what humans do, and I think the next logical step is Mars."

Other space agencies such as NASA have expressed scepticism about the viability of Lansdorp's plan, saying the technology to establish a human colony on Mars does not exist.

Mars One, which is registered as a non-profit organization, says on its website the mission is a decade-long endeavor, with funding intended to come from the global audience of an interactive, televised broadcast of every aspect of the mission.

"We are not quite there," Lansdorp said of the funding requirements, refusing to say how much has been raised but noting that more than 78,000 people have applied to join the mission, becoming astronauts.

In April, Mars-One said that the first four volunteers should land on Mars in 2023 after a seven-month journey. New crews would be sent every two years, according to Lansdorp.

Among those gathered in Washington on Saturday was Christine Rambo, a 38-year-old student librarian from New Jersey, who described Mars as the "next great age of exploration."

"It is like Columbus discovering America," she said. "It is so exciting and such a great achievement, I want to be a part of it."