Earth’s Magnetic Field. Vital to life on Earth Due to the Iron core Protects us from cosmic rays...

Post on 21-Jan-2016

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Transcript of Earth’s Magnetic Field. Vital to life on Earth Due to the Iron core Protects us from cosmic rays...

Earth’s Magnetic Field

Earth’s Magnetic Field

• Vital to life on Earth

• Due to the Iron core

• Protects us from cosmic rays

• Prone to reversal

Cosmic Rays

• High energy, fast moving particles from the Sun and outside the solar system

Cosmic Rays

• Hit upper atmosphere and create gamma rays

• One cosmic ray can create hundred of gamma rays

Cosmic Rays

• Gamma rays can __________ materials

• This can cause damage to tissues and ________

Cosmic Rays

• Luckily, the Earth’s magnetic field deflects _________ particles, like cosmic rays, along its lines of force towards the _______

The Aurora Borealis

QuickTime™ and aSorenson Video 3 decompressorare needed to see this picture.

The Aurora Borealis

• Caused by particles, ionised by cosmic rays, recombining with electrons and emitting light

QuickTime™ and aSorenson Video 3 decompressorare needed to see this picture.

Earth’s Magnetic Field

Earth’s Magnetic Field (p56)

• Has lines of _______ and _______ like any magnet

• Caused by _______ in the Earth’s _____ core