Mission blasts off for Mars to grab a piece of its moon

Japan's space agency launched a spacecraft this week that will attempt to retrieve the first-ever samples from Mars's moons. The MMX mission is headed for Phobos, a potato-shaped moon just 20 kilometers across, where it will collect 10 grams of dust and return it to Earth by 2031. Scientists hope the material will finally answer a decades-old question: did Mars capture these tiny moons from the asteroid belt, or were they created when an ancient impact scattered debris around the planet? The sample analysis could provide a definitive answer within weeks of arrival.