The Sun's Surface and Solar Activity

I. The Quiet Sun

• Solar photosphere & "limb darkening":

• Granulation (convection in photosphere):

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II. The Active Sun

• Sunspots (photosphere):

*Rotation of sun -- movie

* Anatomy of a sunspot:

 

• What causes sunspots? Magnetic fields

• Prominences & Filaments (choromosphere; same loops of glowing gas seen from side or above):

 

• Coronal Streamers in visible light (coronagraph):

* usually constant...

* ... but, Coronal Mass Ejections (movie).

• Corona seen in Xrays:

* Holes (cool, dark) and hot-spots (bright):

 

• Flares (chromosphere & corona):

* Movie1, Movie2.

• Solar Activity in all its forms is seen at sites of magnetic fields:

 

• What does the sun look like today?

* U.S. National Solar Observatory

* French Bass2000 archive

* SOHO satellite

 

• SOHO photos courtesy of SOHO (ESA & NASA)
• Most ground-based photos courtesy of Bass2000.