Tardigrades in space

'tun' state. They quickly revive when re-wetted. They have been described as the toughest animals on Earth. == Proposals ==

In 1964, R.M. May and colleagues proposed that the tardigrade Macrobiotus areolatus would be a suitable model organism for space experiments because of its exceptional radiation tolerance. In 2001, R. Bertolani and colleagues proposed tardigrades as a model for a study of animal survival in space. As terrestrial experiments on tardigrades proceeded, knowledge of their survival abilities grew, enabling K.I. Jönsson in 2007, and then other researchers such as Daiki Horikawa in 2008 and Roberto Guidetti in 2012, == Missions ==

BIOPAN on FOTON-M3, 2007 mission carrying the BIOPAN astrobiology payload (illustrated) exposed tardigrades to vacuum, solar ultraviolet, or both, showing their ability to survive in the space environment. Tardigrades have survived exposure to space. In 2007, dehydrated tardigrades were taken into low Earth orbit on the FOTON-M3 mission carrying the BIOPAN astrobiology payload. For 10 days, in the "Tardigrade Resistance to Space Effects" (TARSE) experiment, groups of Paramacrobiotus richtersi tardigrades, some of them previously dehydrated, some of them not, were exposed to the hard vacuum of space, or vacuum and solar ultraviolet radiation. In contrast, in the "Tardigrades in Space" (TARDIS) experiment, hydrated samples exposed to the combined effect of vacuum and full solar ultraviolet radiation had significantly reduced survival, with only three subjects of Milnesium tardigradum surviving. They concluded that microgravity and cosmic radiation "did not significantly affect survival of tardigrades in flight" and that tardigrades were useful in space research, with implications for astrobiology, where they should be suitable model organisms. The mission was a prototype for the "Living Interplanetary Flight Experiment" (LIFE) which was to have travelled to the Martian moon Phobos on the Russian Fobos-Grunt spacecraft. The spacecraft however failed to leave Earth orbit and was destroyed. Lunar lander Beresheet, 2019 '' Moon lander which crashed, probably destroying its tardigrade payload Despite tardigrades' ability to survive in space, they would still need food, lacking on the Moon, to be able to grow and reproduce. The possibility that tardigrades survived the crash attracted concern about contamination of the Moon with biological material. If they did survive the crash, they would not rehydrate because of the lack of liquid water on the Moon. Spilling tardigrades across the Moon is legal. The Outer Space Treaty only explicitly bans weapons and experiments or tools that could interfere with other missions. Large space agencies typically follow guidelines for sterilizing mission equipment, but there is no single entity to globally enforce these rules. ==See also==