get less then half a one percent at the estimated two to three billion microbial species have had been identified of today the search for a new microbes able to survive in the world's most extreme is helping us address one of the last remaining challenges is there life beyond microbes thrive in an extraordinary range habitats and often when no with the life forms could exist these include freezing conditions very similar to the permafrost at mars and on other planets to the search for life on Mars is a session detective story it's about looking for those telltale signatures have life maybe changes to rocks maybe parts of microbes leftover those parts of the evidence that all come together and tell us that Mars