Mars is emerging from an ice age that began about 400,000 years ago

Mars is emerging from an ice age, according to a new study. Studying the Martian climate and how it changes over time can help scientists better plan future missions to Mars and even understand climate change here on Earth, the study authors say.

Models had already predicted that Mars underwent several rounds of ice ages in the past, but little physical measurements ever confirmed those predictions. Today’s study, published in the journal Science, is the first to map the ice deposits on the north and south pole and confirm that Mars is emerging from an ice age, in a retreat that began almost 400,000 years ago. The researchers also calculated just how much ice accumulated over the poles; the amount is so big that if it were spread throughout Mars, the entire planet would be covered by a 2-foot thick layer of ice.