Join NASA Solar System Ambassador and solar archaeologist, Marie Kesten Zahn. Build like an astronomer! The movement of the Sun can be used to track the passage of time and to mark important dates during the year like solstices and equinoxes. For centuries, all over the world, people have been making observatories using the environment around them. Join Marie for solar archaeology, build your own solar observatory like Stonehendge, and other fun activites about the Sun!