The question of life on Mars has been intriguing humanity for not one century. Today, scientists do not have direct evidence of the existence of living organisms on the Red Planet. However, it is also impossible to completely exclude such a possibility. The answer depends on what one means by the word \"life.\" What We Know About Mars Today Mars is a cold planet with a thin atmosphere. The average temperature is about minus 60 degrees Celsius. The atmosphere is mainly composed of carbon dioxide. Liquid water cannot exist stably on the surface today. However, billions of years ago, Mars was warmer and wetter. There were rivers, lakes, and possibly oceans on the surface. This is confirmed by riverbeds, deltas, and minerals that are formed only in the presence of water. Why Scientists Do Not Exclude Life on Mars Factor Significance for Life Water in the Past Liquid water is a key condition for life as we know it Underground Oceans There may be liquid water under polar caps and deep in the ground Organic Molecules Found in Martian rocks but may have a non-biological origin Methane in the Atmosphere May be released by bacteria or geological processes Radiation High levels on the surface, but protection is higher in the deep ground Where Life Is Sought on Mars Location Why Interesting Crater Lake There was a lake and river delta in the past Underground Oceans Possible liquid water under polar caps Deep Grounds Protection from radiation and possible water reserves Geyzers and Methane Emissions Potential energy sources for microorganisms Ancient Riverbeds Traces of water and sedimentary rocks What Rovers Have Found Rovers have discovered organic molecules ... Read more