NASA's First Weather Report From Jezero Crater on Mars A pre-launch photo of the Mars Environmental Dynamics Analyzer (MEDA) system, which is now providing atmospheric measurements to engineers from Jezero Crater on Mars. Credits: NASA/JPL-Caltech. Full image and caption › 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.