question what made the fourth planet from the sun turn red and barren? >> it's going from that polar desert, geological world, kind of boring rocks. to this exciting, blooming world with a history that does include warm, wet times. climate change. dynamic atmosphere landslides. buried ice, unbelievable. >> reporter: scientists believe that mars may have looked like earth with warm temperatures. we do believe that mars had liquid water, correct? >> absolutely. literally unasailable. >> reporter: collectinging the pressures in the atmosphere will give those analyzing the data a better understanding of the climate change under the red planet's history. >> we expect to learn now the modern mars working in detail. to see its climate space. how mars may have lost a magnetic field.