Researchers have found that human sperm retains its complete viability within the different gravitational conditions found in outer space.
The results could be a huge boost to zillionaires like Amazon founder Jeff Bezos who see the "colonisation" of space as an answer to the Earth's ever threatened resources.
"If the number of space missions increases in the coming years, and are of longer duration, it is important to study the effects of long-term human exposure to space in order to face them," said Montserrat Boada from Dexeus Women's Health in Barcelona, whose group worked with microgravity engineers from the Polytechnic University of Barcelona.
"It's not unreasonable to start thinking about the possibility of reproduction beyond the Earth," Boada said.
The study was performed using a small aerobatic training aircraft (CAP10), which can provide short-duration hypogravity exposure.