During Thursday it has come up into prominence that National Aeronautics and Space Administration's (Nasa) Mars rover Curiosity couldn't justify it's investigation for methane in the planet's atmosphere. Methane gas happens to be a strong evidence of life on Earth.
The rover landed on Mars in August 2012 for observation whether the planet most like Earth in the solar system has otherwise ever had the chemistry and conditions to support microbial life. Beyond the past decade, scientists using Mars orbiters and telescopes on Earth have announced formation of methane in the Martian atmosphere. The gas breaks down in sunlight, so its presence on Mars indicated that either biological activity otherwise a recent geologic event was responsible for its release.
Image Source - Nasa