Solar luminosity

almost all the light comes from a layer...

Average temperature of the photosphere (*surface?)

limb darkening

decribe limb darkening using
-density and lines of sight
-diagram

at which position do we see to the greatest depth below the
surface of the cloud, and at which position do we see to the shallowest depth
below the surface of the cloud?

differential
rotation

sidereal period

solar activity cycle

wave speed

energy of a photon

corona

if the beam came from
a source which produces a continuous spectrum it would typically contain