To think that something as common as ordinary water is the key that we are looking for--the key to finally determining once and for all if there was or is life on Mars. More than any other place in our solar system, Mars is the most like Earth and probably is the most likely to have had life on it one time or another. We know that Mars has polar ice caps and clouds, which means that there is water, but on my voyage what we would need to find is water in its liquid state because that is the key to the presence of life.
As commander of the Rover, I would want to explore areas that would possibly contain liquid water, such as dry riverbeds, the ice in the polar caps, and near rock types that only form when water is present. Most of the surface has already been explored by past missions, so our biggest hope would be finding pockets of water under the surface.
Therefore, I would guide the Rover carefully over these areas, digging under the surface looking for pockets of water underground.
Besides our search for water, we would also look for other signs of life that existed. If we were able to find minerals with carbon, then we would know that life might have existed there because all living organisms that we know of on Earth need carbon. We know that most the atmosphere of Mars contains carbon dioxide, so maybe some of this carbon could have been used in the formation of life. I would command the Rover to take mineral samples near the same places we would look for water so that we could test them for the presence of carbon.
Finding water and carbon on Mars would make it...