Animation depicting Mars during its Hesperian Period, a geological time period extending roughly 3700-3000 million years ago. This Period is characterized by widespread volcanic activity and catastrophic flooding that carved immense outflow channels across the surface. The Hesperian is an intermediate and transitional period of Martian history. During the Hesperian, Mars changed from the wetter and perhaps warmer world of the Noachian to the dry, cold, and dusty planet seen today (the Amazonian Period).