Book 27, Question 38 · Video
What is hoarfrost, and why does it make trees look furry white?
Hoarfrost forms on clear, cold, still nights. Water vapor in the air turns straight into ice crystals on cold surfaces such as twigs, grass, wires, and fence posts. The crystals grow into spiky feathers and needles, which can make a whole tree look furry and white. It is different from frost on a window, because it grows outside on thin things that cool off fast. When the Sun rises, it melts away.
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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 is hoarfrost, and why does it make trees look furry white?
The Big Idea
On some cold mornings, trees look furry and white! That's hoarfrost. Let's find out how it forms.
Cold Still Nights
Step one: Cold Still Nights. Hoarfrost forms on clear, cold, still nights. Water vapor in the air turns straight into ice crystals on cold surfaces such as twigs, grass, wires, and fence posts.
Spiky Feathers
Step two: Spiky Feathers. The crystals grow into spiky feathers and needles. They can make a whole tree look furry and white.
Different Frost
Step three: Different Frost. Hoarfrost grows outside on thin things that cool off fast, unlike frost on a window. When the Sun rises, it melts away.
A Closer Look
Let's take a closer look! Nights are still. Vapor freezes. Twigs get coated. Sunrise melts it.
Quick Facts
Quick facts! The word hoar comes from an old word for gray or white, like an old person's hair. Spiky feathers of ice. Trees look furry. Melts at sunrise.
Think Like a Scientist
Now, think like a scientist! On a very cold morning, go outside with a grown-up. Dress warmly! Look at frost on grass or a fence. Draw the spiky crystals. Notice which side they grow on.
Outro
Hoarfrost forms on clear, cold, still nights when water vapor turns straight into ice crystals on twigs, grass, and wires. Spiky feathers make trees look furry and white until the Sun melts them. Science is amazing! Remember, every big discovery starts with a small question. Keep looking, keep learning, and keep asking why! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!