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Occurrence of Aurora

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In the ionosphere, the ions out of the solar wind collide with the oxygen atoms and also with the nitrogen from the Earth's atmosphere. Here the energy which is released during the collisions causes a colourful glowing type halo around the poles, this is known as an aurora. Studies say the most active auroras occur, at the time when the solar wind is the strongest.

Aurora is a light show that is caused when the electrically charged particles from the sun come in collision with the particles of gases such as oxygen and nitrogen that are present in the Earth's atmosphere. An aurora is usually caused by the streams of electrified particles (that is emitted by the sun) which is bounded in the magnetic field of the earth.


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Aurora is a luminous phenomenon that occurs in the Earth’s atmosphere, this occurs mainly in the higher latitudes of both hemispheres. Auroras occurring in the Northern Hemisphere are known as the Aurora Borealis, Aurora Polaris, also they are commonly known as the northern lights. While, in the Southern Hemisphere it is known as aurora australis, also known as southern lights.   

Auroras are generally caused by the interrelated action of the energetic particles which are mainly the electrons and the protons located in the solar wind with other atoms of the upper atmosphere. This interaction remains confined to the higher latitude regions. They are located in the oval-shaped zones which surround the Earth’s magnetic poles and also maintain an orientation that is according to the sun. During the time of low solar activity, this auroral zones shift towards the pole. While, during the periods of solar activity, these auroras occasionally extend towards the middle latitudes, like for example, the aurora borealis which has been seen as far as in the south which is 40° latitude in the US. The Auroral emissions generally occur at altitudes of about 100 km (approximately 60 miles). Though, they may occur anywhere which is between 80 and 250 km (that is about 50 to 155 miles) above the Earth’s surface.

Aurora Atmospheric Phenomenon 

Aurora is at times referred to as the ‘polar light’ which is predominantly seen in the regions of higher altitudes like in the Arctic and the Antarctic regions. This aurora is caused by the gush of electrified particles, they are emitted by the sun. 

Auroras are commonly seen in the latitudes which are around 70 degrees. They normally occur in a band which is known as the ‘auroral zone’. The auroral zone is about 3 to 6 degrees measured in terms of width in latitude. It lies between 10 to 20 degrees from the geomagnetic poles. 

Aurora Borealis 

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The northern lights, or the aurora borealis which offers an entrancing or dramatic, magical presentation that fascinates all those who see are a sight to cherish. 

In the centre of this solar system, the sun is located which is a yellow star and this sustains life on our planet. The sun got many magnetic fields that distort and twist within itself as our parent star rotates around on its axis. While, when these fields become knotted together, they quite burst and create sunspots. They occur in pairs the largest sunspot can be quite almost several times the size of the planet Earth's diameter.

As the temperature at the centre rises and falls, the sun boils and turns into bubbles. These particles escape from the star and then escape from the sunspot, hurtling the particles of plasma, known as the solar wind, into space. It thus takes these winds which are around 40 hours to reach the Earth. After they reach the earth, they can cause dramatic displays which are known as the aurora borealis. 

Aurora Polaris

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The northern lights are considered one of the several astronomical phenomena, they are called the polar lights (also known as the aurora Polaris), they act as shafts or as the curtains of the coloured light which is visible on an occasion in the night sky.

Polar lights (or the Aurora Polaris) are a natural phenomenon that is found in both the northern and southern hemispheres. This streak of light is truly awe-inspiring. These northern lights are also known by their scientific name, which is known as aurora borealis, and the southern lights are also called the aurora australis.

Fun Facts

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This is a picture of Aurora Australis. It is a display of the southern lights, which are quite manifesting by itself and as a glowing loop, this is an image of a part of Earth's Southern Hemisphere, which is taken from space by the astronauts. 

FAQ (Frequently Asked Questions)

1. What are the Forms of Auroras?

Ans. Auroras are of different forms which are as follows:

  • A mild glow, which is located near the horizon. They can be close to the limit of visibility, but this can be distinguished from the moonlit clouds as the stars are to seen undiminished through this typical glow.

  • The Patches or the surfaces which are similar in look to the clouds.

  • Arcs are the curve that is across the sky. 

  • Rays are light with dark stripes that are across the arcs, which reaches upwards by great amounts.

2. What are Sunspots?

Ans. Sunspots are a temporary phenomenon that occurs on the Sun's photosphere, this appears as spots that are darker than the surrounding areas. Sunspots are the regions of the reduced surface temperature that is caused by concentrations of magnetic field flux which inhibits convection. These sunspots usually appear in pairs of the opposite magnetic pole.

3. What is Hemisphere?

Ans. The word "hemisphere" is usually derived to refer to the two halves of the Earth, but the word ‘hemisphere’ is also used to identify the two halves of the brain. 

Talking about the earth’s hemisphere, there are generally four hemispheres to be considered that are – Northern Hemisphere, Southern Hemisphere, Eastern Hemisphere, and Western Hemisphere. The Equator, or the line which is of 0 degrees latitude, divides the Earth into two hemispheres that are Northern and Southern hemispheres.