Big things have small beginnings. The latest findings of NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft have clued researchers in to the nature of Mars’s upper atmosphere, a lesser-known area in the mystery of the Red Planet. Thanks to this new research, published this month in Science, scientists are homing in on the atoms, ions, and molecules that Mars’s atmosphere is losing to space. They’re also coming to understand how the planet’s wind circulation relates to changes in temperature. All these little details could have major impacts on our understanding of Earth’s next-door neighbor, and even inform us about the nature of climate on our home planet. This video explains the steps MAVEN has taken to detail Mars’s upper atmosphere, placing its discoveries within the context of previous Mars research.