Auroras, also commonly referred to as the southern and northern lights, are a luminous atmospheric...
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What are Aurous Auroras, also commonly referred to as the southern and northern lights, are a luminous atmospheric phenomenon that generally appear as bright colourful bands of light. Auroras are often visible in the night sky in both the northern and southern regions of the Earth.
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The bright visually pleasing colours commonly associated with auroras are the result of electrons colliding with oxygen and nitrogen molecules in the Earth’s atmosphere. As these molecules become energized, then cool from their energized state, they emit actual light that can be seen by the naked human eye.
Transcript of Auroras, also commonly referred to as the southern and northern lights, are a luminous atmospheric...
What are AurousAuroras, also commonly referred to as the southern and northern lights, are a luminous atmospheric phenomenon that generally appear as bright colourful bands of light. Auroras are often visible in the night sky in both the northern and southern regions of the Earth.
What cause them to appear?
Auroras are believed to be caused by charged high energy particles from the solar winds that are trapped within the atmospheric magnetic field of the Earth. As these charged particles spiral back and forth along the lines of the magnetic field, they become visible nearest to the north and south magnetic poles where these magnetic lines disappear into the body of the Earth.
HOW IS SUN CONNECTED TO THE AURORAS
The bright visually pleasing colours commonly associated with auroras are the result of electrons colliding with oxygen and nitrogen molecules in the Earth’s atmosphere. As these molecules become energized, then cool from their energized state, they emit actual light that can be seen by the naked human eye.
Why do they only appear near the poles?
Auroras, sometimes called the northern and southern (polar) lights or aurora (singular: aurora), are natural light displays in the sky, usually observed at night, particularly in the polar regions. They typically occur in the ionosphere. They are also referred to as polar auroras. In northern latitudes, the effect is known as the aurora borealis, named after the Roman goddess of dawn, Aurora, and the Greek name for north wind, Boreas, by Pierre gassendi in 1621.
Are they seen at any particular time of year?
In northern regions like Alaska, the best time to view aurora is around the equinox (March and late September-October) because this time of year offers the best trade-off between mild weather and dark skies. During the summer months, night skies are not dark enough to view aurora, and in midwinter temperatures in the -40 degree range make outdoor aurora viewing somewhat unpleasant.
Why are they different colours?
Have you ever noticed the different colours in streetlights? Some are a dark yellow colour while others have a blue or purplish light. How about neon signs? They have many different colours.Streetlights and neon signs are filled with gas. When they are turned on, an applied voltage energizes electrons in the gas. These electrons strike the gas molecules, which excites them to emit light. The colour of the light you see depends on the type of gas.
