The Aurora Borealis

Composer: Carl Orff,in the year 1936

Perormed by: The Boston Symphany Orchestra

MUSIC BY: Carmina Burana

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Since the World began, Solar Lights have been an Integral part of our planet Earth. They do not depend at all on the human activity, but rather on that of the Sun and the terrestrial magnetic field. The Dawn is not as one once believed (until some 70 years ago), that causes the reflection of solar light on the ices of the Arctic.

However, it is indeed the Sun, which is responsible for the Polar Lights as the turbulent surface of the Sun rejects into the space the atoms and the subatomic particles (protons, electrons). At the time of violent solar storms, a great quantity of electrons and protons coming from the Sun arrive in the terrestrial atmosphere and activate the nitrogen and oxygen atoms, which become suddenly luminous and produce the splendid veils (ribbons or curtains) of coloured light, which are the polar lights. They are named Polar because once arrived in the terrestrial atmosphere, the particles are taken by the trap of the magnetic field, which forces them to move towards the magnetic poles either north (Northern Lights) or in the south (Aurora Australis) Dawn with the shape of a thin elliptic band (the auroral oval) is centred on the magnetic north and south poles, i.e. approximately within 700 meters of the geographical poles. The size of this form depends on the solar activity: the more the Sun is quiet" and the solar wind calm the oval is smaller; conversely the more the solar wind strikes the terrestrial magnetic field with force and gusto, more the dawn becomes broad and extends.

Aurore North & South

The Affect of the Solar atmosphere

The temperature of the solar atmosphere is several million degrees Kelvin (temperature °C = temperature °K - 273,15).

At these temperatures, the collisions between the particles are so violent that the hydrogen atoms break up into electrons and protons.

This “material" is called ionized plasma.

The Solar wind is when this plasma moves away from the sun in all the directions. transports the Solar Magnetic Field into interplanetary space. The speed and the density of this solar wind vary greatly. They are larger when the wind comes from the active areas of the sun, like the solar spots or protuberances.