Ten Equations that changed the world. (You once told me that some day you wanted me to tell you all about science and engineering. How long have you got? It's all so fascinating and we take it too much for granted.)
mechaddiction: “One of two prints from artist Kevin Dart’s Space Shuttle series celebrating the Challenger and Columbia. These two incredible shuttles and their crews completed 36 successful missions and spent over 300 days in space. Some highlights.