Gas giants like Jupiter may start out as tiny pebbles.The massive gas giants in our solar system — Saturn and Jupiter — were likely the first planets to form. But scientists aren’t quite sure how that process got started. In a study published Wednesday in Nature, researchers present one possible explanation: Tiny pebbles quickly accumulated to form their cores.
Previously, most believed that the cores of these huge planets must have been made during the collision of fairly large bodies — rocks almost as big as planets in their own right. The new theory, which used computer modeling to simulate the formation, suggests that tiny particles (tiny in the cosmic sense, at about a foot across each) would be more likely than large chunks of rock to form gas giants.