For years, scientists have picked apart data transmitted from Mars probes to find signs of life on the red planet. But since the Martian landscape is too harsh to support most kinds of life, some scientists in St. Louis travel to remote places to study life that thrives in extreme environments.
If life exists on Mars, scientists think it’s likely in the form of tiny organisms that live underground, because the surface receives large amounts of radiation. Mars missions have also revealed that the planet has large concentrations of a toxic, salty substance called perchlorate. Life on Mars would likely be able to tolerate dry, salty environments, so researchers have looked for similar places on Earth.