The surface of the Sun is about 10,000 degrees Celsius.The corona (atmosphere above the surface) is about 10,000,000

Question: The surface of the Sun is about 10,000 degrees Celsius.The corona (atmosphere above the surface) is about 10,000,000 degrees Celsius. Why so much hotter? Where is it getting its heat?
- Keywords:
  atmosphere,
  corona,
  sun,
  surface
Asked by salej014 to Emma, Jimmy, Janet, Niall, Simon on 18 Mar 2013.
- James Holloway answered on 18 Mar 2013:
  
  There are a few ideas as to why this is. One is that there is energy stored in the magnetic field of the sun, and this field can deposit lots of energy in the sparse conora via lots of micro flares erupting hundreds of times an hour on the surface.
  
  But this is one of the questions science is still trying to answer.
- Niall Crawford answered on 18 Mar 2013:
  
  The ions move faster through the corona, and give off more heat.

Question: The surface of the Sun is about 10,000 degrees Celsius.The corona (atmosphere above the surface) is about 10,000,000 degrees Celsius. Why so much hotter? Where is it getting its heat?