Space is the most hostile environment we know of. The temperature is close to absolute zero, in a vacuum there is not a drop of oxygen and the amount of radiation that comes from the stars is lethal. That is why astronauts who move in this environment must protect themselves with thickspace suits weighing more than 130 kilosincorporating layers ofreflective materialssuch as Gore-Tex and Nomex, as well as an ultra-resistant plastic calledKevlar, which avoids possible tears or perforations produced by fragments of space debris.
But not all living things need so much protection. As published by the magazineCurrent Biologyin his next issue, there are some exceptional animals that can survive “naked” in these extreme conditions. It is about thetardigrades, also known aswater bears, tiny invertebrates 0.1 to 1.5 millimeters in size that normally live in the film of moisture that covers mosses and ferns, although they have also been found under 5-meter layers of ice and ocean depths of 6000 meters. When things get ugly, for example in cases ofextreme drought, these animals can stay instandby, going from having 85% body water to only 3%. And so they stay long enough until the situation improves and they can pick up their lives where they left off.
To test the effectiveness of this tactic in space, Ingemar Jonson and his colleagues sent a group of tardigrades into space aboard the spacecraft.FOTON-M3of the ESA, launched in September 2007, and exposed them to the harsh conditions of outer space, including dangerousultraviolet radiation up to 1000 timesmore intense than those that reach the earth’s surface. Once they returned, the survivors not only “came back to life” but were even still able to reproduce. “It is a mystery how they resist these radiations, which normally destroy any tissue or cell,” the study authors say in surprise.
