Speaker 1: Welcome to brain Stuff from how Stuff Works dot com
Speaker 1: where smart Happens. I am Marshall Brain with today's question.
Speaker 1: If Nature of Horrors a vacuum, then why doesn't the
Speaker 1: vacuum of space sec away all of Earth's atmosphere? From
Speaker 1: our daily experience with nature, it does seem like Nature
Speaker 1: of Horrors a vacuum. If you create a vacuum inside
Speaker 1: a container here on Earth, Nature will fill the container
Speaker 1: with air very quickly if you puncture that container. On
Speaker 1: the other hand, we know that outer space is a
Speaker 1: giant vacuum. Outer Space is infinitely larger than Earth, so
Speaker 1: ninety nine point nine percent of our universe is a vacuum.
Speaker 1: Based on this, it might be better to say that
Speaker 1: nature loves a vacuum, so why doesn't the vacuum of
Speaker 1: outer space suck away our atmosphere. Say you're standing on
Speaker 1: Earth holding a glass bottle. If you attach the bottle
Speaker 1: to a vacuum pump, pump out all the air, and
Speaker 1: then seal the bottle, the bottle contains a vacuum. If
Speaker 1: you put a hole in the bottle, air rushes in.
Speaker 1: But the reason it rushes in is because of the
Speaker 1: air pressure around the bottle. Standing on the ground, we
Speaker 1: are standing in an ocean of air that rises many
Speaker 1: miles above us. The air molecules stack up on each
Speaker 1: other and they create the pressure of fourteen point seven
Speaker 1: pounds per square inches sea level. The higher you rise
Speaker 1: in the atmosphere, the shorter the stack of molecules, so
Speaker 1: the lower the pressure at sea level. It's the weight
Speaker 1: of all of the molecules stacked above the bottle, fourteen
Speaker 1: point seven pounds of them in every square inch that
Speaker 1: forces the molecule into the punctured vacuum. If you were
Speaker 1: to travel in a rocket to the edge of the atmosphere,
Speaker 1: you would find that there is no air pressure. Instead,
Speaker 1: individual air molecules are zipping around in the vacuum of space.
Speaker 1: The molecules can zip anywhere they like, but they tend
Speaker 1: to zip towards the Earth because the Earth's gravity acts
Speaker 1: on them, just could acts on anything else with mass.
Speaker 1: The reason the vacuum of space doesn't attract the molecules
Speaker 1: is because there is no suction to the vacuum space.
Speaker 1: There's no air pressure forcing things into that vacuum. All
Speaker 1: there is in space is molecules traveling through the vacuum.
Speaker 1: You can see that there's no danger of the vacuum
Speaker 1: sucking our atmosphere away, But it turns out that there
Speaker 1: is another force that could strip away the atmosphere. That
Speaker 1: force is called solar wind. Fortunately, the atmosphere is protected
Speaker 1: from the solar wind by the Earth's magnetic field. Do
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