Elon Musk's long-standing ambition to build a human colony on Mars may be running into a very human obstacle. New research suggests human sperm struggles to function properly in space, raising serious questions about whether people can reproduce beyond Earth.
The findings, published in Communications Biology, have unsettled scientists and space agencies alike, especially as missions to Mars shift from theory to preparation. Rockets are improving and habitats are being designed, but the question of sustaining life across generations remains uncertain and far from settled.
