This is Scientific American's 60-second Science, I'm Christopher Intagliata. The Apollo missions brought back 842 pounds of rock and soil from the moon... nearly 2200 different samples. But there's one sample that planetary scientist Meenakshi Wadhwa says is the most interesting of all: "Apollo 1-0-0-8-5." Neil Armstrong collected it on Apollo 11. "He was about to step back into the lunar module and he turned around and had this rock box and he saw little spaces in there and he knew that these geologists on earth would be just so excited to study these materials, he just scooped up I think nine scoops of soil that he put into the box." It became one of the most well studied samples of the Apollo missions, she says. And a geologist named John Wood, at the Smithsonian, noticed white flecks of rock in the soil... which he identified as a rock type called anorthosite. And it clued him in to the moon's ancient past. "And this was quite a leap of imagination but he proposed that the whole of the moon had at one time in the past,