Phenomenon
Rayleigh Scattering
The reason the sky is blue.
Scattering of light by particles much smaller than the wavelength, varying as 1/λ^4 — scatters blue sunlight in Earth's atmosphere preferentially.
Overview
Scattering of light by particles much smaller than the wavelength, varying as 1/λ^4 — scatters blue sunlight in Earth's atmosphere preferentially.
See also
Solar Eclipse
When the Moon stands between Earth and Sun.
Lunar Eclipse
When Earth's shadow falls on the Moon.
Meteor Showers
Cosmic dust burning in our atmosphere.
Aurora (Northern/Southern Lights)
Solar wind painting the upper atmosphere.
Supernova
The catastrophic death of a massive star.
Planetary Conjunction
When two worlds appear to meet in the sky.