What is dark matter and why do scientists think it exists?

There’s something invisible in space that helps hold galaxies together, and we call it dark matter.

Imagine you're playing with your toys on a really bouncy trampoline. You jump up, and the trampoline stretches out around you. Now imagine there are other kids jumping too, but you can’t see them, they’re just making the trampoline stretch more than it should. That’s kind of what scientists think is happening in space.

Galaxies, like our Milky Way, are like those kids on the trampoline. They move in a certain way because of gravity, the same force that keeps your feet on the ground. But when scientists look at how fast galaxies spin or move, they find out something strange: there’s more gravity than there should be.

That means there must be something else, something we can’t see, adding extra gravity. Scientists call this extra stuff dark matter. It doesn’t shine like stars, and it doesn’t block light like clouds. But it’s everywhere, holding things together in the universe just like invisible glue.

So even though we can’t see it, scientists know it's there because of how things move, just like you can tell other kids are on the trampoline without seeing them. There’s something invisible in space that helps hold galaxies together, and we call it dark matter.

Imagine you're playing with your toys on a really bouncy trampoline. You jump up, and the trampoline stretches out around you. Now imagine there are other kids jumping too, but you can’t see them, they’re just making the trampoline stretch more than it should. That’s kind of what scientists think is happening in space.

Galaxies, like our Milky Way, are like those kids on the trampoline. They move in a certain way because of gravity, the same force that keeps your feet on the ground. But when scientists look at how fast galaxies spin or move, they find out something strange: there’s more gravity than there should be.

That means there must be something else, something we can’t see, adding extra gravity. Scientists call this extra stuff dark matter. It doesn’t shine like stars, and it doesn’t block light like clouds. But it’s everywhere, holding things together in the universe just like invisible glue.

So even though we can’t see it, scientists know it's there because of how things move, just like you can tell other kids are on the trampoline without seeing them.