This is a diagram of diffusion of air through a window.
Diffusion means the slow steady movement of individual molecules from one region to another. As solid as a pane of glass can seem, molecules of air can easily diffuse, or pass through the glass. This can readily be noticed on a cold winter night! Diffusion of gas accounts for the way the smell of baking cookies can drift into the living room from the kitchen!
Shop Windows to the Universe Science Store!
Learn about Earth and space science, and have fun while doing it! The games
section of our online store
includes a climate change card game
and the Traveling Nitrogen game
You might also be interested in:
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
The mesosphere of Uranus 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
AU stands for Astronomical Units. Distances in space are too large to measure in Earth standards like miles or kilometers. For distances too large to measue in AU, we use light years. A light year is the...more
The solar wind is formed as the Sun's topmost layer blows off into space carrying with it magnetic fields still attached to the Sun. Gusts and disturbances form in the solar wind associated with violent...more
For a planet to be affected by a blob of material being ejected by the sun, the planet must be in the path of the blob, as shown in this picture. The Earth and its magnetosphere are shown in the bottom...more
The aurora we are most familiar with is the polar aurora. This is what people are referring to when they speak of the northern or southern lights. But there are other less-known auroral activity, such...more
This figure shows the effect of the aurora on the atmosphere. When FAC's enter the atmosphere and create the aurora, they warm the atmosphere impulsively. This impulse travels throughout the atmosphere...more