Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to CuriousKidsUS@theconversation.com. Are planets in the solar system that are ...

Our solar system used to have nine planets. Astronomer Mike Brown, also known as “the man who killed Pluto,” said he got hate mail from kids and obscene calls at 3 a.m. for years after his ...

All eight of the solar system’s “major” planets appear in this illustration, but the actual number of planetary bodies orbiting our star is far greater. Digital Vision/Getty Images.

All seven of the other planets in our solar system are about to become visible at once in a great planetary alignment – here’s how to spot the celestial show. Close. Advertisement.

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 ...

This process, called accretion, is how everything in the solar system – planets, moons, comets and asteroids – came into being. Advertisement Article continues below this ad ...

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 ...

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 ...

This process, called accretion, is how everything in the solar system – planets, moons, comets and asteroids – came into being. Telescopes can see young solar systems being born.