Kelvin

Kelvin–Helmholtz waves are found across the universe wherever two materials of different density move past one another. They can be seen in cloud formations around Earth and have even been observed in other planetary atmospheres in our solar system.

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Inside the magnetosphere, the density of the space plasma — charged particles, like electrons and ions — is much lower than the plasma outside, where the solar wind prevails. The boundary, called the magnetopause, becomes unstable when the two different density regions move at different rates. Giant swirls, called Kelvin Helmholtz waves, form along the edge like crashing ocean waves.

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Chilling atoms to within one ten billionth of a degree above 0 Kelvin causes them to slow down significantly, making them easier to study.

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Meter, kilogram, second, ampere, kelvin, mole, and candela are the fundamental units of the metric system.

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