Is There Life On Mars?
The age of Mars has been reported to be between 3.6 billion and 1.3 billion years old, "depending on who you ask" These ages come from the estimated ages of meteorites found on Earth that are believed to have originated on Mars. The meteorites were dated using radiometric dating methods.
The most widely accepted theory of life on Mars is that of the recently conceived primitive, or microscopic, life may have existed on early Mars. "A NASA research team at the Johnson Space Center and at Stanford University has found evidence that strongly suggests primitive life may have existed on Mars more than 3.6 billion years ago". Many meteorites have landed on earth, but only 12 are believed to have originated on Mars. These 12 were determined to be from Mars based on comparisons with the 1970's Viking mission's findings on the analysis of the Red Planet's rock and soil. "The conclusive evidence that the SNC meteorites originated on Mars comes from the measurement of gases trapped in one meteorite's interior. The trapped gases match those that Viking measured in the Martian atmosphere".
The team from NASA found the first organic molecules thought to be of Martian origin; several mineral features characteristic of biological activity; and fossils of primitive, bacteria-like organisms inside of an ancient Martian rock that fell to Earth as a meteorite. There was not one finding that led the team to their conclusion, but rather a combination of things. The scientists found a unique pattern of organic molecules, carbon compounds that are the basis of life.
The most compelling evidence supporting the findings was the location of the carbon compounds, plus unusual mineral phases that are products of primitive microscopic organisms on Earth, and the microscopic fossils that support all of this, were in very close
proximity - within a few hundred thousands of an inch of one another. Another theory of ancient life ...