title: Amazonian (Mars)
context: The Amazonian is a geologic system and time period on the planet Mars characterized by low rates of meteorite and asteroid impacts and by cold, hyperarid conditions broadly similar to those on Mars today.[1][2] The transition from the preceding Hesperian period is somewhat poorly defined. The Amazonian is thought to have begun around 3 billion years ago, although error bars on this date are extremely large (~500 million years).[3] The period is sometimes subdivided into the Early, Middle, and Late Amazonian. The Amazonian continues to the present day.
question: When was the Amazonian period?
answers: The Amazonian is thought to have begun around 3 billion years ago, although error bars on this date are extremely large (~500 million years).[3] The period is sometimes subdivided into the Early, Middle, and Late Amazonian. The Amazonian continues to the present day