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.

When I was a kid, there were nine planets. Now we know of thousands! But that includes exoplanets, alien worlds that orbit alien suns.Only eight planets call our solar system home. Or there might ...

All of our solar system’s planets are lining up to parade through the night sky at once. This extraordinary celestial event will see the sky scattered with seven visible planets in what is known ...

Between February 25 and February 28, all seven planets in our solar system will be visible in the night sky. It's known as a planetary parade. You'll need a telescope for some of them, but you ...

The solar system is primarily comprised of our sun — which makes up the vast majority of its mass — and the eight planets, which are split into three subcategories. First up are the rocky ...

– Gavriel, age 10, Paducah, Kentucky 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 ...

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 ...

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 ...

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 ...