Photosphere

• First/deepest layer of the Sun's atmosphere
  • 400 km thick
• The sphere of light
  • Light we see from the Sun comes from this layer
• Gives the Sun an apparent surface
  • Boundary between interior and atmosphere of the Sun
• Granular surface
  • Granules ~1000 km in size
    • Dark rings around granule are cooler spots
  • Several million granules cover the solar surface
  • Lifetime of one granule is only 5-10 minutes
• Around 6000 K

Sun Atmosphere Astronomy