ELI5: Explain Like I'm 5

3M22 Zircon

Do you know what a stopwatch is? It helps us measure time in seconds. But imagine if we had a stopwatch that could measure the age of rocks! That’s how scientists can figure out the age of things that are really old, like rocks and fossils.

Now, one type of rock is called zircon. It’s kind of like a tiny crystal that’s found in rocks. Scientists can use special machines to measure how old the zircon is, and by extension, how old the rock is.

One particular zircon was found in Australia, and scientists measured it to be 3 meters and 22 centimeters (3m22) old! That’s a super long time! It’s actually 4.4 billion years old, which means it’s one of the oldest pieces of Earth ever discovered.

By studying rocks and zircons like this, scientists can learn more about what happened on Earth billions of years ago, like how the planet formed and how life evolved. It’s like they’re playing detective to unravel the mysteries of the past!