This is a diagram of diffusion of air through a window.

Diffusion

Diffusion means the slow motion of molecules from one place to another.

As solid as a pane of glass can seem, molecules of air can easily pass through the glass. You can easily notice this on a cold winter night!

Diffusion is the name for the way the smell of cookies baking can drift into the living room from the kitchen!

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Jupiter's Mesosphere

The mesosphere of Jupiter is a region of balance between warming and cooling. That essentially means that nothing happens there. Except for diffusion, the atmosphere is still. Upper reaches of the atmosphere,...more

Uranus' Mesosphere

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The SAR Arc

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This figure shows the effect of the aurora on the atmosphere. When FAC's enter the atmosphere and create the aurora, they heat the atmosphere suddenly and abruptly. This creates an impulse which travels...more

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