Page 151 - Grasp English C1+ (Student Book)

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Science Polaris, the North Star

axis – an imaginary line through the centre
of the Earth, about which it turns

hemisphere – one half of the Earth
latitude – the distance, measured in
degrees, north and south of the Equator
equator – the imaginary line around the
centre of the Earth

horizon – the visual point where land or sea
meets the sky

A. Discuss with a partner.

1. Do you know the names of any stars or constellations?
2. Why is the North Star so important?

B. Answer the questions.

1. Why is Polaris so well known?
2. How was it used by travellers on land and at sea in the past?
3. What navigational devices did sailors use in the past?
4. How might Polaris’ role as the North Star change in the future?

C. Discuss with a partner.
1. Can you see Polaris in your country?
2. What other celestial bodies can you identify in the night sky?

Project

D. Choose another celestial body and prepare a presentation
about it. You may like to think about:
• who discovered it and when
• its significance to science

• its size, composition, distance from the Earth, etc.

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