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Aurora is a natural phenomenon that resembles a beam of light burning in the lining of the ionosphere of a planet as a result of the interaction between the planet’s magnetic field is owned by the charged particles emitted by the Sun (solar wind). Aurora in the rush by many people to take some pictures, because Aurora including beautiful natural phenomena and stunning.

On Earth, auroras occur in the area around the North Pole and South magnetic poles. Aurora that occurs in the northern region known as the Aurora Borealis. This is because in Europe, the aurora often looks reddish in the northern horizon as if the sun will rise from that direction. Aurora borealis is always going on between September and October, March and April. The phenomenon of the aurora in the south, known as Aurora Australis has similar properties, but sometimes the aurora appears at the top of the mountain in a tropical climate.

Aurora results from the emission of photons in the Earth’s atmosphere, above 80 km (50 miles), of the ionized nitrogen atom regains electrons, and atomic oxygen and nitrogen from the excited state back to the ground state. They are ionized or excited by collisions of solar wind and magnetospheric particles are channeled and accelerated down along the Earth’s magnetic field, the excitation energy is lost by the emission of photons, or by collisions with atoms or molecules.

Aurora is classified as diffuse or discrete aurora. The diffuse aurora is a featureless glow in the sky which may not be visible to the naked eye even in a dark night and defines the extent of the aurora zone. Discrete aurorae are sharply defined feature within the diffuse aurora which vary in brightness from just barely visible to the naked eye to bright enough to read a newspaper at night .Discrete aurorae are usually observed only in the night sky because they are not as bright as the sunlit sky .

Oxygen is unusual in terms of return to the ground state, it can take three-quarters of a second to emit green light and emit up to two minutes for the red. Collision with another atom or molecule will absorb the excitation energy and prevent emissions. Due to the very top of the atmosphere has a higher percentage of oxygen and rarely distributed such collisions are rare enough to allow time for oxygen to emit red. Collisions become more frequent advanced into the atmosphere, so that the red emission do not have time to occur, and eventually even the green light emission is prevented.

This is why there is a color with a height differential, red oxygen at high altitude dominates, then the oxygen and nitrogen blue green / red, and finally nitrogen blue / red when the collision preventing oxygen from emitting anything. Green is the most common of all the aurora. Behind it is pink, light green and red mixture, followed by pure red, yellow (mixture of red and green), and lastly pure blue.