Aurora lights

Brittle, A. L., Ohkura, H. (2005). Centrosome maturation Aurora lights the way to the poles. Current Biology CB, 15, R880—R882. 

Aurora Lights in the upper atmosphere (from about 90 to 300 km altitude) produced by the excitation of atmospheric gases by energetic particles the localized areas in the two polar regions where aurora are typically observed are determined by the detailed topology of the magnetosphere. 

Fireworks displays are fascinating to watch. Neon lights and sodium vapor lamps can transform the skyline of a city with their brilliant colors. The eerie phenomenon of the aurora borealis is an unforgettable experience when you see it for the first time. All of these events relate to the generation of light and its transmission through space. 

The aurora borealis, a spectacular atmospheric light show shown in Figure 7-25. originates in the thermosphere. In addition to electromagnetic radiation, the sun emits a steady stream of protons and electrons. The Earth s magnetic field deflects most of these particles, but some reach the thermosphere above the north and south poles of the... 

The aurora borealis is due to the emission of photons by excited-state atoms and molecules in the thermosphere, hi the Northern Hemisphere, the aurora is called the Northern Lights. 

It has been known for centuries that many compounds emit visible radiation when they are exposed to sunlight. Luminescence phenomena, such as the aurora borealis, phosphorescence of the sea, luminous animals and insects, phosphorescent wood, etc., have fascinated man since antiquity, being reflected in the early scientific literature. Aristotle (384-322 b.c.) appears to be one of the first philosophers to recognize cold light in dead fish, fungi, and the luminous secretion of the cuttlefish [1],... 

A slightly more in-depth study of colour is afforded by The Physics and Chemistry of Colour by Kurt Nassau, Wiley, Chichester, 2001. The author describes many everyday examples of colour, from peacock tails through to the Northern Lights, Aurora Borealis. Its Chapter 1 is an overview, and is probably a little highbrow at times, but overall is a fascinating read. 

Nineteenth-century atomic theory could not explain why the aurora exhibits a limited range of specific wavelengths, rather than the full visible spectrum. Early in the twentieth century, however, scientists developed a revolutionary new model of the atom. This model, and the theory that supports it, helped to account for many puzzling phenomena that the existing atomic theory had failed to explain. Among these phenomena are the characteristic colours of the northern lights. 

The aurora of the dawn is coming and the light of day. In the name of the Father, the Son, and the Holy Spirit, by the sign of the Holy Cross, free us Our Lord from our enemies and all evil. Amen."... 

The beautiful northern lights, or aurora borealis, are often observed in the Northern Hemisphere at high latitudes. The light is partly produced by excited O atoms in the upper atmosphere. 

Scientists have fixed 960 km as the approximate upper limit of the atmosphere. Aurora Borealis or the Northern light is the basis for this conclusion. 

At polar latitudes in winter, massive discharges of electricity in the upper atmosphere can be seen as the very beautiful aurora borealis. The solar wind and cosmic rays ionize O and N atoms about 80 km above the earth s surface the ionized N and O atoms emit faint light as they regain an electron and return to the ground state. 

Misuse example The earth s auroras—the northern and southern lights—illustrate how energy from the sun travels to our planet. —Science News, 149, June 1,1996. This sentence blurs understanding of the process by which energetic charged particles from the sun interact with the earth s magnetic field and our atmosphere to result in the aurorae. 

People travel thousands of miles to see the aurora borealis (the northern lights) and the aurora australis (the southern lights). Once incorrectly believed to be reflections from the polar ice fields, the auroras occur 100 to 1000 km above Earth. 

Such events account for the appearance of the very pretty, mysterious displays of lights in the sky in the polar regions of the northern and southern hemispheres, viz., the aurora borealis and... 

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