Discover three science milestones from December 4! Explore how the International Space Station began taking shape, how Alfred Hershey’s research helped show that DNA carries genetic information, and how Gemini 7 tested the limits of human spaceflight. These events make engaging science starters for middle and high school. Explore 132 daily STEM events in the December Science on This Day activity set, with interactive HTML, slides, spreadsheet and printable PDF.