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The Strange Northern Lights
If you find yourself in (1) Norway or other northern places at night, you might be lucky enough to see the aurora borealis, or northern lights. Seeing (2) the lights is an amazing experience. Sometimes they look like (3) a band of green colour across (4) the sky, and at other times they look like (5) curtains of purple, red and green. What causes them? Energy from (6) the sun stirs up atoms high up in (7) the atmosphere. The Earth is like (8) a large magnet and it traps (9) atoms. These atoms then release their energy, and this produces light. Exactly (10) the same thing happens in the far south, where (11) the lights are known as (12) the aurora australis.