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The presenter, Vicky, visits the city of Tromsø in Norway - the most northerly city in the world. It is so far north, there are several weeks of the year when the Sun does not rise at all. We see her obvious confusion as she wakes up at nine o’clock in the morning to find it is still dark. Vicky then visits a weather station which has a daylight measurement device.

Students could explore day and night in relation to the rotation of the Earth and its movement around the sun. A classroom solar system could be set up using a lamp as the sun and a globe. Students could consider that one rotation of the Earth makes one day. They could reinforce this by sticking a picture of a person over Scotland and rotating the globe to show when he or she is in the light and when they are in the dark. Students could discuss what they do in the light and dark and note that this transformation marks one day. Introduce that there are seven days in a week, about four weeks in a month and twelve months in a year.

Challenge students to send the little picture person to a place where it is dark all day. They could spin the globe, note the light falling over it and identify where no light was falling no matter what time of the day it is. Students could then consider if this is the same all year round, are these places always dark? A demonstration of the Earth’s movement around the sun to form one year could then be shown. Students could shout stop at any point in its movement and rotate the globe to see if the paper person is still in permanent darkness. They could consider whether there are any new places that are now in permanent darkness. On completion students could colour on a map of the Earth the areas where at some time in the year they are in constant darkness. Students could discuss the location of these and discuss the reasons why they experience constant darkness.

Alternatively, students could consider the impact this constant darkness has on the lifestyle of people living in these places.