The Northern Lights

(The aurora)

What are the Northern lights?

• The bright dancing lights of the aurora are actually collisions between electrically charged particles from the sun that enter the earth's atmosphere. The lights are seen above the magnetic poles of the northern and southern hemispheres. They are known as 'Aurora borealis' in the north and 'Aurora australis' in the south.

How it works

The sun when active omits 6-7 solar flare bursts a day which omit ions. These charged ions would be dangerous if not for the earths magnetic field. They reach the northern/southern poles and react with the particles releasing energy in the form of light. You might be able to see the aurora without a solar flare because of the solar wind but there is no way you could miss the solar flare aurora

How are there different light colours?

• Different coloured light results from different coloured ions • Green is the most common• Red, blue and brown have also been observed

As the electrons enter the earth's upper atmosphere, they will encounter atoms of oxygen and nitrogen at altitudes from 20 to 200 miles above the earth's surface. The color of the aurora depends on which atom is struck, and the altitude of the meeting.

• Green - oxygen, up to 150 miles in altitude• Red - oxygen, above 150 miles in altitude• Blue - nitrogen, up to 60 miles in altitude• Purple/violet - nitrogen, above 60 miles in altitude

When and where to see the northern lights?

• Seeing the northern lights, or the aurora borealis, as they are also known, is a jaw-dropping and mystical moment.

• The lights are at their most frequent in late autumn and winter/early spring. Between the autumn equinox and spring equinox (21 September - 21 March), it is dark between 6 pm and 1 am, and you have maximum chances of spotting the lights. However, the weather is also of importance