Episodes

Do you wish you could have an extra hour in the day? Well, if you can wait a very long time, you’ll get it. That’s because the length of the day is increasing, and has been for the last billion-plus years. Scientists recently studied a large Cretaceous mollusk with unprecedented precision. Mollusk shells grow like tree rings, adding a little bit each day. The researchers used lasers to drill tiny holes in the shell, each the size of a red blood cell—like microscopic core samples. From these they...

75 years ago, the U.S. exploded its first atomic bomb, in the New Mexico desert. It was the culmination of 5 years of hurried development. Throughout World War II, Germany hoped to use the incredible energy density of uranium and plutonium to build a devastating weapon. To beat them to the bomb, the U.S. assembled teams across the country—130,000 staff and scientists, many of whom had fled Europe to avoid Nazi persecution. In July 1945, team leaders gathered to watch that first detonation from 1...