The difference between aurora blue and blue

The difference between aurora blue and blue is that blue is ordinary blue without light, and aurora blue is the kind of blue with light.

Blue, a cool color, has a high frequency (second only to violet light) in the visible light of electromagnetic waves, and the frequency is 600-700 THz (corresponding to the wavelength of 500-430 nm in the air), belonging to high-frequency light. Blue is one of the three primary colors and four psychological colors of light, representing the color of the sky.

Because air molecules and dust in the air scatter sunlight in Rayleigh way (the scattering intensity is proportional to the fourth power of frequency), they scatter more high-frequency light (green, blue and purple light) than low-frequency light (red, orange and yellow light), so the clear sky is blue. Because seawater absorbs more low-frequency light (red, orange and yellow) than high-frequency light (green, blue and purple), seawater will appear blue.

The contrasting colors of blue are orange and yellow, and the adjacent colors are green and purple. Blue is a symbol of eternity. Blue represents both melancholy and warmth and gentleness. There are many kinds of blue, and each blue represents a different meaning. In addition, there are many examples of music, books and movies named after blue. For example: blue, white and red trilogy.

It is the coldest of the cool colors. Blue is very pure, and it is usually associated with ocean, sky, lake and universe. Pure blue is the color of clear sky, showing sunshine, beauty, dream, calmness, rationality, serenity and broadness.

Because of its broad characteristics and rational and accurate image, in commercial design, most commodities or corporate images that emphasize technology and efficiency choose blue as the standard color and corporate color, such as computers, cars, photocopiers and photographic equipment. In addition, blue also represents melancholy, which is influenced by western culture, and this image is also used in literary works or emotional commercial design.

The above content source: Baidu Encyclopedia-Blue