Science 3: The Earth
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The moon isn't the only one going through phases. Today we're going to learn about a bunch of different phases the Earth went through before it became the one we know and love today. Yep even the super embarrassing molten lava teen years. Sorry, Earth.
|Elementary and Middle School||3rd Grade|
Whatever it might be, we can all agree that homes change over time – for better or for
And the same can certainly be said about the big home for all of our homes – Earth.
Think about the Earth we have today. [Earth appears]
It's full of life!
Plants and trees that grow, giving us food and oxygen…
…An atmosphere perfect for breathing…
…Lakes of fresh water… [Lake appears]
And hey, the temperature isn't so bad either! [People sunbathing on beach]
Seriously, you think winters are cold here?
Try negative 195 Fahrenheit on Mars.
You won't be dreaming of a white Christmas in that weather… [Man in an ice block]
…because you'll be frozen.
This is the Earth we know today.
But believe it or not, Earth wasn't always so pleasant.
Let's rewind about, say, 4.5 billion years. [Earth spins fast]
When Earth was just a young planet, it wasn't exactly the welcoming place we know and love
Think of this as the Earth's rebellious teen years.
Lots of eye rolling. [Earths eyes rolling]
And it was hot.
Like, really hot.
Like completely volcanic.
And also covered in totally poisonous gas. [Earth covered in gas]
Not exactly the kind of place we'd love to call home, huh?
But just like any brooding teenager going through an emotional phase...
the Earth ended up changing…
Eventually, it reached the point where the atmosphere contained enough oxygen to support
life, along with the eventual presence of water on the Earth and in the air. [Small tortoise appears in a forest]
Then came along this pesky asteroid that scientists believe changed the atmosphere and caused
most of the animals on Earth to go extinct.
Which was sort of a bummer.
Then Earth got warm, and plants and animals thrived again. [Earth turns into plants and animals]
And then it got cold.
Like, multiple Ice Ages cold.
…Man, what an emotional rollercoaster!
But eventually, things warmed back up a bit, leading us to where we are today.
All in all, the Earth has gone through a whole host of changes in its tiny little four and
a half billion year long lifespan.
And it's still changing today, progressively getting warmer and warmer due to a little [Thermometer increasing]
thing we call global warming.
If only we had an Earth-sized swimming pool for it to jump into...that'd be one cannonball [Earth lands into swimming pool]
we wouldn't want to witness.