Book 23, Question 60 · Video
What Makes the White Trails That Jets Leave Behind?
Jets sometimes leave long white trails in the sky. They look like clouds made by a plane. And that is almost what they are! Long-lasting contrails can turn into wispy clouds.
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What Crafty Clover says in this video
Intro
Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. What makes the white trails that jets leave behind?
The Big Idea
Jets sometimes leave long white trails in the sky. They look like clouds made by a plane. And that is almost what they are!
Hot, Humid Exhaust
Step one: hot, humid exhaust. Those trails are called contrails, short for condensation trails. Jet engines give off hot, humid exhaust.
Cold Air
Step two: cold air. At high altitudes the air is very cold. The water vapor cools quickly and turns into tiny ice crystals, making a line of cloud.
Short or Long
Step three: short or long. In dry air the trail disappears fast. In humid air it can last and spread out.
A Closer Look
Let's take a closer look! The engine releases vapor. The cold air freezes it. A white line appears. It may last or vanish.
Quick Facts
Quick facts! Long-lasting contrails can turn into wispy clouds. Dry air makes short trails. Humid air makes long trails. Contrails form at high altitudes.
Think Like a Scientist
Now, think like a scientist! Look for contrails on a clear day. Note whether they are short or long. What might that tell you about the air? Draw what you see. Tell a grown-up what you discover!
Outro
Contrails form when hot, humid jet exhaust meets cold air and turns into tiny ice crystals. Science is amazing! Keep wondering and keep exploring! Every question is a new adventure, so keep wondering and keep exploring with me! So the next time you wonder about this, you will know just where to start looking. Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!