when you say ‘big magnetic field around the earth’ do you mean the atmosphere if not could you explain what you do mean

Question: when you say 'big magnetic field around the earth' do you mean the atmosphere if not could you explain what you do mean by your term of words?
- Keywords:
  earth,
  magnetism,
  space
Asked by 522tema27 to Joe on 10 Nov 2014. This question was also asked by 294tema33.
- Joe Reed answered on 10 Nov 2014:
  
  Deep inside the Earth at its core, is a huge lump of solid Iron. Around this there is a ocean of liquid metal, mostly Iron and Nickel. Currents in this liquid bit causes Earth’s magnetic field.
  I’m sure you have seen a bar magnet, with a north pole and a south pole. This is exactly the same as on Earth. Lines of magnetic field come out of the north pole, travel round the Earth, and back inside at the South pole. These lines reach far into space, around 5 times the diameter of Earth!
  It is lucky that it exists too. It blocks lots of dangerous radiation from the sun and protects our o-zone layer.

Question: when you say 'big magnetic field around the earth' do you mean the atmosphere if not could you explain what you do mean by your term of words?