NASA Scientist Says Sending Astronauts To Mars Is Best Way To Find Evidence of Life

Microbial life could have existed on Mars long ago and the best way to find proof for it is to send astronauts to the planet, as per NASA's chief scientist Ellen Stofan. During a talk at the Humans to Mars Summit in Washington D.C., Stofan pointed out that the Red Planet may be dry and cold today, however it had liquid water on its surface for extended phases more than three billion years ago.

"Those conditions on Mars, we know, were not that different from the conditions on Earth from when life evolved," Ellen Stofan said. "And life evolved so quickly here on Earth, and in the oceans, that it gives the scientific community a fair amount of confidence that the same conditions did exist on Mars, and that life did evolve there". In addition, the search should not be for alien skeletons but rather fossil microbes "if [Mars] life did indeed go extinct", which will be a tough task to find.  

According to researchers, microbes might have formed on our planet around 4.1 billion years ago, just 440 million years after the Earth formed. However, the life forms stayed simple for a long time. It was only around 800 million years ago that multicellular organisms evolved. During the same time frame, Mars lost most of its atmosphere along with stable surface water. Therefore, according to Stofan, in order to look for life on Mars the hunt should start with something small.

Robots are not capable of searching for such tiny evidences on Mars by themselves; in fact field geologists who study rocks teeming with fossil microbes on Earth can never see the tiny structure. Stofan believes that keeping these factors in mind, the only way to discover whether Mars supported or supports life is to send human scientists to the planet. The search for life on the Red Planet is a strong motivation for sending astronauts to it, and NASA aims to achieve the feat by 2040.