Is it probable that life once existed on Mars?
Ya, it is possible that life had been sustained in Mars.
After many years of research scientists have now found out that life had once existed in Earth's closest planet 'The Mars'. They have discovered some evidences that the atmosphere, climate, and rotation on Mars are same as that of the Earth.
Water :- In mid 17th century Scientists had found out polar ice caps to be present on Mars, William Herschel had proved that the ice caps grow and shrink alternatively in summer and winter of each hemisphere. Also water beneath the surface of Mars could have shield potential life from harsh radiation.
Organic matter :- Scientists claimed that a meteorite(ALH 84001) found in Antarctica in 1966 could contain evidence of traces of life on Mars. The Martian rock contained structures resembling the fossilized remains of bacteria-like lifeforms. But in 2012 it was determined that the these vital ingredients would have been formed on Mars without involvement of life.
Tiny creatures :- Some of the minerals found have various charges and oxidation states. Modern microbiology has determined that these tiny organisms can derive energy by feeding on the martian rocks.
Volcano :- By carefully studying the shape, texture and mix of several minerals scientists have proved that the region was once volcanically active.
Rocks :- After studying the 4.5 billion year old rocks near the planets ancient lakes Scientists have found out that the areas included areas with sedimentary rocks which was made of compacted mud or clay because they are rich in iron and silica, which helps preserve fossils.
Powder from drilling :- The first robot was sent to Mars recently, it has found that the power turned out to be sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon.
Earth life features :- The length of the day and the tilt axis on Mars is similar to that of the Earth.
Scientists thus believe that life could have existed on Mars, that water, atmosphere, and many living creatures once lived on the planet. But over time water would have been lost into the space.