This time the proof for existence of water on Mars hasn’t been gathered by much loved star rover Curiosity. The rock sample was collected by lesser known rover Opportunity. Yes, Opportunity, like Curiosity, also lives on mars.

Opportunity has been an active resident of the red planet since January 2004. The rover recently picked up a rock named ‘Esperance’, all covered in clay.

So what does that mean? Clay on rock forms, when water interacts with the rock. The kind of clay formed depends on the combination of type of rock and water. The clay rich in aluminium found on Esperance indicate that the water that once flowed was very similar to water on Earth. Thus, revealing the presence of water on Mars long long time ago.

So the question is what happened that turned Mars into a dry hot planet today? Where did all the water disappear? Hope we will find some more answers soon.