How was the Solar System made?
About 4.6 billion years ago, a cloud of gas and dust collapsed. The Sun formed in the middle, and the leftover dust clumped together to make planets, moons and asteroids.
Long, long ago, about 4.6 billion years ago, there was no Sun and no Earth. In their place was a huge, cold cloud of gas and dust floating in space.
Something, perhaps the blast from an exploding star nearby, made part of the cloud start to collapse. As it shrank, it spun faster and flattened into a disc, like pizza dough spinning in the air. Most of the gas and dust fell into the middle, which got hotter and hotter until it began to shine. That was the birth of the Sun.
In the disc around the young Sun, tiny dust grains bumped into each other and stuck together, making pebbles. Pebbles gathered into bigger lumps, and those lumps crashed together to make bodies several kilometres across, called planetesimals. Over millions of years, some planetesimals grew into the planets.
Not everything became a planet. Many leftover pieces became asteroids and comets. Meteorites are bits of these leftovers, which is why scientists love them: they are like crumbs from the kitchen where the planets were baked. Some meteorites contain little white blobs that are the oldest solid things from the Solar System, about 4,567 million years old.