Scientists outline the best ways for future Mars rovers to search for ancient life. These include hunting for tiny fossils trapped in volcanic rocks, scanning rocks for certain isotopes more common in living things, and looking for lingering chemical signatures left behind by long-dead microbes.

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Scientists outline the best ways for future Mars rovers to search for ancient life. These include hunting for tiny fossils trapped in volcanic rocks, scanning rocks for certain isotopes more common in living things, and looking for lingering chemical signatures left behind by long-dead microbes.