Audible dot com is the leading provider of digital audio books and spoken word, with over one tho titles to choose from. Audible lets you listen to your favorite books anywhere, anytime. Go to audible podcast dot com slash stuff brain to get a free audio book download of your choice when you sign up today. Welcome to brain Stuff from how stuff works dot com where smart happens. Hi. I am
Marshall Brain with today's question. If Nature of Horrors a vacuum, then why doesn't the vacuum of space sec away all of Earth's atmosphere? From our daily experience with nature, it does seem like Nature of Horrors a vacuum. If you create a vacuum inside a container here on Earth, nature will fill the container with air very quickly if you puncture that container. On the other hand, we know that outer space is a giant vacuum. Outer space is infinitely
larger than Earth. Ninety nine point nine percent of our universe is a vacuum. Based on this, it might be better to say that nature loves a vacuum, So why doesn't the vacuum of outer space suck away our atmosphere? Say you're standing on Earth holding a glass bottle. If you attach the bottle to a vacuum pump, pump out all the air, and then seal the bottle. The bottle contains a vacuum. If you put a hole in the bottle, air rushes in. But the reason it rushes in is
because of the air pressure around the bottle. Standing on the ground, we are standing in an ocean of air that rises many miles above us. The air molecules stack up on each other and they create the pressure of fourteen point seven pounds per square inch at sea level. The higher you rise in the atmosphere, the shorter the stack of molecules, so the lower the pressure at sea level.
It's the weight of all of the molecules stacked above the bottle, fourteen point seven pounds of them in every square inch that forces the molecule into the punctured vacuum. If you were to travel in a rocket to the edge of the atmosphere, you would find that there is no air pressure. Instead, individual air molecules are zipping around in the vacuum of space. The molecules can zip anywhere they like, but they tend to zip towards the Earth because the Earth's gravity acts on them, just like it
acts on anything else with mass. The reason the vacuum of space doesn't attract the molecules is because there is no suction to the vacuum space. There's no air pressure forcing things into that vacuum. All there is in space is molecules traveling through the vacuum. You can see that there's no danger of the vacuum sucking our atmosphere away, but it turns out that there is another force that
could strip away the atmosphere. That force is called solar wind. Fortunately, the atmosphere is protected from the solar wind by the Earth's magnetic field. From on this and thousands of other topics because it how stuff works dot com. Audible dot com is the leading provider of digital audio books and spoken word, with over one thousand titles to choose from. Audible lets you listen to your favorite books anywhere, anytime.
Go to audible podcast dot com slash stuff brain to get a free audio book download of your choice when you sign up today.