The polar regions are the coldest places on Earth:
The Arctic and Antarctic circles are lines of latitude going around the Earth that mark the outer limit of the two polar regions. They are found at 66oN and 66oS of the Equator.
Inside these circles, the tilt of the Earth causes long summer - and short winter - days to occur. At the poles themselves, six months of unending sunlight alternate with a six-month period of darkness. Many places within the Arctic circle are nicknamed 'the Land of Midnight Sun' because the sun hardly ever disappears and it can be daylight for nearly 24 hours in the summer.
The night skies in the polar regions can be filled with gently rolling coloured lights. In the Arctic they are called the Aurora Borealis and in Antarctica they are called the Australis. They are formed as solar winds hit the Earth's magnetic field and release light particles.