Post on 21-Jan-2016
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