Extensive research has shown the potential for microorganisms to survive in some of the most extreme environments on Earth. Our current understanding of diverse life on Earth implies that, even though the surface of Mars is very inhospitable to life, it is possible that there may be indigenous microorganisms on Mars, especially in the protective subsurface. Ultimately, a better understanding of microbial diversity on Earth is needed to determine the limits of life to help determine the potential for life on Mars and other exoplanets.
Part of the book: Into Space