Tardigrades, also known as waterbears or moss piglets, are tiny (microscopic or near-microscopic) multi-celled extremophiles found in a variety of environments. Tardigrades are most easily found in lichens and mosses but are also known to live in marine and freshwater sediments, soil, sand dunes, and beaches. They have been found at oceans depths of 13,000 feet and altitudes above 20,000 feet in the Himalayas. The exist at every latitude from the poles to the equator.

Tardigrades can enter a dormant state in which they can survive for years without water. They have shown the ability to survive temperatures as high 300º F and close to absolute zero (-459º F). They can tolerate radiation lethals 1000 times greater than the mean lethal dose for humans (5000-6000 Gray units versus 2.5). They can survive pressures of 1,200-6,000 atmospheres and the vacuum of space.

Clark Lindsey’s Space For All blog provided a pointer to the following video about a citizen scientist who studies tardigrades.


The ability of tardigrades to survive in space was first shown by the European Space Agency’s Biopan-6 experimental platform during the Russian Foton-M3 mission in 2007.

Tardigrades went into space again in 2011 aboard the final flight of the Space Shuttle Endeavour, as part of an experiment called BIOKIS-TARDIKISS to be performed on the International Space Station during Expeditions 27 and 28.

The Planetary Society developed the two -phase Living Interplanetary Flight Experiment to test whether tardigrades and various other organisms could survive in space. The first phase of the experiment (Shuttle LIFE) was conducted on the final flight of the Space Shuttle Endeavour. The second phase, Phobos LIFE, was designed to determine whether the organisms could survive long-term exposure to space during a three-year interplanetary mission. The experiment failed, however, when the Russian Fobos-Grunt probe, which was carrying the experiment, failed to leave Earth orbit.

Although professional researchers are studying tardigrades aboard the International Space Station, the opportunity still exists for citizen scientists to gather additional data on suborbital flights, such as those offered in our Call For Experiments. There are 1,150 species of tardigrade known to science, so there are a lot of possibilities still to be investigated.


Written by Astro1 on September 7th, 2012 , Astrobiology Tags:

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