LONDON, July 27 (UPI) -- Future manned space exploration will be the province of adventurers rather than state-backed missions, Britain's astronomer royal says.

In an interview 40 years after the first manned moon landing, Cambridge University Professor of Cosmology and Astrophysics Martin Rees said most future space mission would likely be robotic, BBC News reported Tuesday.

Manned space exploration would become "a cut-price, high-risk program ... which would be an adventure more than anything practical," Rees said.

"Those walking on the surface of planets like Mars are likely to be adventurers of the sort who conquered Everest," he said.

"The moon landings were an important impetus to technology," Rees said, "but you have to ask the question what is the case for sending people back into space?"

The need for manned missions would get weaker with every advance in robotics and miniaturization, he said.

"I hope that some people living today will walk on Mars," Rees said, "but I think they will do this not for any practical purpose but with the same motive as those who climb Everest or the pioneer explorers."