A Russian scientist says manned Martian flights could render a male astronaut sterile, shrink his musculature and weaken his bones.
Valeri Polyakov's comments came during an international symposium on gravitational physiology that began Monday at Moscow's Russian Academy of Sciences, Novosti reported.
"A flight to the Red Planet and back will certainly destroy the reproductive function, what with long exposure to hard radiation. Weightlessness, too, will have its effect causing muscular atrophy and excreting calcium from the bones," Polyakov said.
A male astronaut headed for Mars ought to be no younger than sixty, he said.
"It would be unwise and downright cruel to send selfless boys to Mars, even if they have a long space record."
Polyakov gained the endurance record for space flight after he spent 438 days at the Mir orbital station.
Topics set for discussion include changes in the immune system in zero gravity and the effects of zero gravity on the vestibular apparatus and the ear.
Participants will exchange information about the effects of hypergravity and microgravity on the growth and development of animals, cell biology and the biochemistry of plants.
