Immigrant life on Mars MAY 20 2014
If there wasn't life on Mars before, there might be now. Before NASA sent Curiosity to Mars, it was thoroughly cleaned of all traces of contaminants. But swabs of rover's surfaces taken before it was sent to Mars have revealed 377 different strains of bacteria that potentially could have made the trip. Some of them may have even survived.
A study that identified 377 strains found that a surprising number resist extreme temperatures and damage caused by ultraviolet-C radiation, the most potentially harmful type. The results, presented today at the annual meeting of the American Society for Microbiology, are a first step towards elucidating how certain bacteria might survive decontamination and space flight.