Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky A cloud of collapsing gas created our Sun, the first thing to ...

A cloud of collapsing gas created our Sun, the first thing to form in our solar system. This happened about 4½ billion years ago. Then the planets began to emerge, as the billions of particles of gas ...