AlQa'dah 15, 1434, Sep 21, 2013, SPA -- NASA's Mars rover Curiosity has come up empty-handed in its search for methane in the planet's atmosphere, a gas that on Earth is a strong indicator of life, Reuters quoted officials as saying. The rover landed on Mars in August 2012 to determine whether the planet most like Earth in the solar system has or ever had the chemistry and conditions to support microbial life.