NASA’s MAVEN spacecraft has reached Mars

MAVEN has arrived in Mars’s orbit after traveling 442 million miles in the course of 10 months to get there. It won’t land on the red planet but instead study Mars’ atmosphere from above to answer questions about its climate change, NASA says. NASA’s MAVEN craft will live up to its formal name — the Mars Atmosphere and Volatile Evolution craft — by helping scientists figure out how ancient Mars changed so dramatically into the planet we know today. It is the first mission devoted to studying the upper Martian atmosphere as a key to understanding the history of Mars’ climate, water and habitability. “The evidence shows that the Mars atmosphere today is a cold, dry environment, one where liquid water really can’t exist in a stable state,” said Bruce Jakosky, MAVEN principal investigator, during a mission preview briefing last week at NASA headquarters in Washington. “But it also tells us when we look at older surfaces, that the ancient surfaces had liquid water flowing over it.” So where did the planet’s water and carbon dioxide go?