Nasa's Spirit Mars rover may have spotted signs of life on the red planet in 2007

It's been five years since NASA ended the Spirit rover's mission, but now, researchers say the robot may have discovered traces of life during its Mars investigation. A team of geoscientists has discovered that silica deposits from a region on the red planet dubbed'Home Plate' closely resemble those that form in Chilean hot springs at El Tatio. On Earth, these complex finger-like structures arise from a combination of biological and non-biological activity, suggesting a similar process may have taken place on Mars. The researchers compared opaline silica structures found at Home Plate (on left) with those from hot spring discharge channels at El Tatio (on right). The silica deposits on Mars were discovered after Spirit's right front wheel failed in 2007, forcing the robot to drag it across the ground like a plow near Home Plate, an eroded deposit of volcanic ash.