Baby Jupiter was smacked by a planet 4.5 billion years ago

Jupiter has long been hailed as the mighty "king of planets" thanks to its massive size compared to most of the other planets in our solar system. It's huge, and it's mostly made of gas, making it difficult for scientists to know what lies deep beneath its thick cloud cover. NASA's Juno spacecraft has been studying the planet in detail for over eight years now, and it's returned some surprising observations about the planet's core. Now, a new study from an international team of researchers may o...