- from Earth
Scientists believe that about 5 billion years ago, a massive explosion sent gas and dust swirling into space.
It might have been caused by an exploding star. Gravity made the dust clump together. Over the next 500 million years, the Sun formed. Then the eight planets took shape. So did the five dwarf planets, 181 moons, and countless asteroids and comets.
Earth was born about 4.5 billion years ago. Our planet’s history is so long that scientists measure it using the geologic timescale. Modern humans have been around for only the last 1.6 million years. Here’s a brief history of the world.