What is a Planet?

Imagine you're looking up at the night sky. You see stars that twinkle, but some bright lights seem to move around! Ancient sky watchers called these 'wandering stars' planets. Today, we know planets are big, round space balls that zoom around a star, like our Sun. They are super important members of our solar system family!

For a long, long time, people thought the Sun and Moon were planets too! Then, as telescopes got better, we discovered more amazing things in space. Scientists had to figure out what truly counts as a planet. It’s like having rules for a game, but for space objects!

To be a planet, a space object needs three special powers! First, it must orbit our Sun. Second, it needs to be so big that its own gravity squishes it into a round shape, like a giant ball. Third, it has to be the boss of its path, clearing out any smaller space rocks or dust bunnies that get too close!

Pluto used to be called a planet, but it didn't quite make the cut for the third power. It shares its path with lots of other icy objects! So, scientists decided Pluto is a 'dwarf planet' instead. It's still a cool space object, just not a full-fledged planet in our solar system anymore.