The surface of Mars has been dry and desolate for a billion years or more. One of the biggest mysteries of Mars is determining what happened to all the water. Why do we care so much about water? Determining the history of water on Mars will give us clues as to how the climate and geology of the planet evolved over time. Also, when humans eventually travel to Mars, we will need to know what resources are available. However, possibly the most intriguing aspect of water is that on Earth, everywhere that we find liquid water, we find life. If it was wet in the past, was (or is) their life on Mars?