Britain should rethink its policy ban on astronauts, a report written for the Royal Astronomical Society (RAS) says.
The report warns Britain risks being isolated on the international stage if it continues its longstanding refusal to fund the human exploration of space.
The RAS expert panel says the cost of joining other nations with astronaut programmes could be some Ј150m a year.
But the scientific, educational and economic benefits would be worth it, it argues, reports BBC.
"We find that profound scientific questions relating to the history of the solar system and the existence of life beyond Earth can best perhaps only be achieved by human exploration on the Moon or Mars, supported by appropriate automated systems," they said in the report.
Robots will play an important role in the space programs but human involvement will also be essential.
"Autonomous robots alone will be unable to realize those scientific goals in the foreseeable future," said Professor Frank Close, of Exeter College at Oxford University.
Ken Pounds, an emeritus professor of space physics at the University of Leicester, said it may not happen for another 10-15 years but he believes several nations will be involved in human space flights to the Moon and beyond.
The cost of British participation would be about 150 million pounds a year, which would have to be sustained for 20 years at least.
"We're talking about an overall commitment of 3 billion pounds," he added.
The experts said British involvement would have educational, commercial and political benefits and provide inspiration for future generations.