"In this engaging and eye-opening book, astrobiologist Sean McMahon compellingly argues that we may find evidence of past life on Mars--likely before your life is over. There are now thousands of astrobiologists around the world, using the tools of modern science to answer some of the most intellectually exciting questions that have ever been asked: What is life? How can it originate from nonliving matter? How does it evolve and proliferate across vast spans of space and time, and what forms might it take on alien worlds? How can we find it? The search for life on Mars is a mainstay of this research program and has never been more advanced, more sophisticated, or closer to success. Governments have invested billions of dollars in nuclear- and solar-powered robotic rovers equipped with high-resolution cameras, spectrometers, and other instruments capable of sniffing out the remnants of ancient Martians. Soon, a new suite of spacecraft and robots will collect promising rocks from the Martian surface and return them to Earth, where new, ultraclean laboratories will receive and interrogate them. It is now a mainstream scientific view that Mars about four billion years ago was a temperate, Earth-like planet, glittering with rivers, lakes, and seas. When life began on Earth, Mars was certainly habitable and perhaps even inhabited. Although we have not definitively found fossils on Mars, McMahon says, we have learned how to find them. We know where to look: which regions and landscapes could once have supported life and preserved its remains in rocks and minerals.

We know what to look for: how the traces of living organisms can weave through the fabric of ancient rocks, transmuted into minerals or transcribed into the subtle language of fossil carbon molecules. We know how to detect these and other signals billions of years old using state-of-the-art microscopes and other instruments. NASAs Curiosity and Perseverance rovers have already encountered "potential biosignatures" that astrobiologists are now investigating. But we have also learned, from spectacular mistakes, tangles with natures "fake" fossils, and other cautionary tales, how to be careful--how not to be fooled when nonliving matter imitates life. Drawing on cutting-edge ideas and findings in planetary science, geology, microbiology, and paleontology, McMahon makes a persuasive and alluring case that fossils may soon be discovered on Mars--and that a profound new understanding of life in the universe will follow"-- Provided by publisher.