NASA’s First Weather Report From Jezero Crater on Mars Perseverance’s MEDA will help us understand how to prepare astronauts for a future on the Red Planet. The weather often plays a role in our daily plans. You might put on a light jacket when the forecast calls for a cool breeze or delay your travel plans because of an impending storm. NASA engineers use weather data to inform their plans, too, which is why they’re analyzing the conditions millions of miles away on Mars. The Mars Environmental Dynamics Analyzer (MEDA) system aboard NASA’s Perseverance rover first powered on for 30 minutes Feb. 19, approximately one day after the rover touched down on the Red Planet. Around 8:25 p.m. PST that same day, engineers received initial data from MEDA.