It is now being more than speculated that NASA's intention to send human beings to Mars will also likely involve sending human sperm along for the journey.
In order to ensure a healthy population, NASA deems it necessary to create a diverse supply of sperm for the potential for a genetically diverse, Martian colony.It is unknown whether or not reproductive cells can survive the radiation of outer space, however.
A new study, though, shows mouse sperm keeping for as long as nine months on the International Space Station where radiation levels are about 100 times that of Earth, yet these sperm produce healthy, fertile offspring.
Steven Peck, a bioethicist and biologist at Brigham Young University in Provo, Utah who was uninvolved in the actual research, confirms that "this work is important." Other researchers follow Teruhiko Wakayama who is a biologist at the University of Yamanashi in Kofu, Japan, and they sent frozen sperm from 12 mice to the ISS back in 2013.
Astronauts kept the sperm samples frozen at -95ºC for 288 days.The team stored all the sperm on earth from the same mice for the same duration at the same temperature.
When the samples returned to Earth, Wakayama and his team examined them for evidence of DNA damage due to radiation, and the sperm from the ISS exposed to higher radiation levels revealed more fragmented DNA than those kept on Earth and subjected to the same conditions but lower radiation levels.
When scientists injected the space-mouse sperm into fresh eggs transferred to surrogate mothers, though, the females actually birthed 73 "space pups," which remains just as many as would've been expected from normal sperm.