Hello, welcome along, Explorer. It's time for a very quick adventure. It's the fun kids science

mid-weekly. It's your quick, bite-sized science special on a Wednesday. My name is Dan.

So happy you've been sending in your questions. This week, you can find out my theory on what happened to the dinosaurs.

Also, why pangia separated.

You can hear how animals and plants get their names and how long a light year actually is.

Let's get to it then.

This one is from Edward, who is 12, who wants to know. How do we know the

dinosaurs when extinct by a meteor? Weird, isn't it right? Because we are so certain about

something that happened 65 million years ago. But we know. Because there is a line in the earth

underground. It's a layer called the KT boundary. In that layer, deep, deep,

deep underground, there are strangely high levels of an element called iridium. And it's rare to find

iridium on earth, but it's very common in meteorites. Now buried under that are fossils of

dinosaurs that we found, but not above really.

That's strange, isn't it?

So it suggests that the dinosaurs were around and then they were buried under a layer of earth.

And in that layer of earth, you find things that are mainly found in meteorites.

If you add one and one together, you come up with two, and that must mean, well, the meteorites hit the earth and the dinosaurs were killed because of it.

Also, they've worked out that that layer of earth called the KT boundary is about 65 million years old, and that's when we kind of think that the dinosaurs went

extinct. We also know that there's an enormous crater in Mexico called Chixulub, which is likely

to have been made by meteorite impact, which is about 65 million years old. It's amazing,

isn't it? It's like being a detective at a crime scene figuring all this out and they've worked

it all out.

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