A Russian Bion-M spacecraft, filled with mice, lizards and other animals, returned to Earth after 30 days in space with about half its mice and all its gerbils dead.
The Bion-M experiment, launched from Baikonur, Kazakhstan, on April 19, carried 45 mice, 15 geckos, 18 Mongolian gerbils, 20 snails and a number of different plants, seeds and microorganisms, according to a Russian state news site. About half of the mice died, but the lizards reportedly survived. The Mongolian gerbils all expired, apparently due to an equipment failure, said Vladimir Sychev of the Russian Academy of Sciences, according to AFP.
It is unclear at this moment whether it was the harsh environment of weightlessness or equipment failure that caused the mortalities.