The Northern Lights
The solar wind constantly streams toward the Earth, but dont worry because a protective magnetic fields surrounds our planet. The same magnetic field that makes your compass point north also steers the particles from the Sun to the north and south poles. The charged particles become trapped in magnetic belts around the Earth. When a large blast of solar wind crashes into the Earths magnetic field first gets squeezed and then the magnetic field lines break and reconnect.
Watching auroras is fun and exciting, but normally you can only see them in places far north like Alaska and Canada. The movement of the aurora across the sky is usually slow enough to easily follow with your eyes but they can also pulsate, flicker, or even move like waves. During solar maximum, auroras are seen as far south as Florida, even Mexico!
We hope you are able to travel to far-north places like the Arctic Circle and see the Northern Lights at least once during your lifetime. We know you will never forget it!
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MODULE 1 Nice to meet you
牛津英语七年级上册全册预备级表格式教案
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MODULE 5 Healthy food
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七年级英语上册单词表
Unit 6 Do you like bananas
Comic strip
Unit 5 Do you have a soccer ball
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I’m going to be a basketball player
Starter Moudle 4
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七年级英语 Unit 1 Getting to know you教案
七年级英语上册Unit 9-10复习提纲
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七年级英语上册module 9 unit 1导学案(外研版)
Unit 4 Food教学案
I want to be an actor教案
What color is it
Starter Moudle 2-1
Unit 6 Fashion教学案
七年级英语 Unit 4 Places and activities教案
Unit7 How much are these pants导学案
七年级英语上册module 9 unit 2导学案(外研版)
Unit 9 How was your weekend
Unit6 Pets教案
Unit 5 Poems about life
七年级英语上册unit5单元复习教案
Starter Unit 3 What color is it 学案
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