Plans are being drawn up to send mice into orbit on board their own love-mobile where they can have low-gravity sex.
Researchers at the privately funded Mars Society are designing a capsule which will simulate conditions on Mars.
It could be put into orbit for two months which is enough time for its occupants to reproduce and their offspring grow to adulthood.
The capsule would then be brought back to Earth to see if low gravity had affected the development of the young mice.
Scientists behind the so-called Translife Mission say it would help plan for the long-term missions necessary to explore Mars.
With the right backing the flight could take place in 2003 aboard a tiny capsule which simulates Martian gravity by spinning like a centrifuge.