From the Museum of Flight web site, "During the April 4 “Free First Thursday” from 5 to 9 p.m., the Museum will celebrate NASA Climate Day with activities and presentations exploring the science of climate change and what we can do about it. Other activities show how satellites have helped scientists study climate change, and what that data means to Earth and us. Visitors can measure their carbon footprint, learn about the difference between climate and weather, and what “fossil fuel” means. The Museum and Climate Day activities are free, April 4 from 5 to 9 p.m."