Sign up for the Starts With a Bang newsletter Travel the universe with Dr. Ethan Siegel as he answers the biggest questions of all. From World War II until 2024, the US stood unchallenged as the scientific leader of the free world. Across practically every discipline — physics, materials science, astronomy, chemistry, biology, medicine, geology, etc. — American scientific missions and initiatives, often in collaboration with European, Canadian, Asian, and many other global partners, brought us n...