Scientists have identified deep underneath the surface of Mars a complex and vast network of lakes which cover the entire planet. Such a discovery has left Scientists hinting of a past presence of life:
While the red planet is mostly dry and desolate today, a growing body of evidence shows it used to be covered in large bodies of water above and below ground. [source]
Using the feedback from their cameras on board their craft which was orbiting Mars, the scientists
What they found was a complex interconnected system of water bodies that have long since dried up.
The scientists also analysed the minerals found within the craters to try and understand the history of the planet. Clays, carbonates and silicates were found which are all linked with the emergence of life.
Next year, together with the Russian space agency Roscosmos, the ESA intends to launch their ExoMars rover to explore the planet’s surface in a search for aliens. [source]