We are coming up to the winter solstice on December 21st when it will be the shortest day of the year. At this time of year we can watch the sun rise above the horizon on our way to school and see sunset in the afternoon at school. By the time we leave school it is dark.
Why is the day so short in winter and so long in summer?
This is because the earth tilts on its axis. If you live in the northern hemisphere it is winter, the days are short and it is colder, because we are tilted away from the sun.
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This diagram is not to scale. The sun is much, much bigger and much,much further away! |
When there is a lot of activity on the sun a solar wind is created and particles fly across space towards earth. The particles are drawn in to the earth at its magnetic poles. This creates the aurora borealis or 'northern lights'. When this happens we can see the lights if we look towards the north.
We are lucky to have a dark night sky which is mostly unaffected by light pollution. Since we also have more hours of darkness we are more likely to get a good view of the lights which are sometimes called 'The Merry Dancers' in Orkney. The closer to the north pole you live the better the view you get! Here is a video of the aurora borealis from the north of Norway.
Of course the best view is from space.
Have you seen 'The Merry Dancers'?