THE STELLAR CORE: The ONLY place where thermonuclear fusion occurs, because it possesses high temperatures and densities. For instance, the Sun's core produces:

        L_o = 4 x 10²⁶ Watts!!     (that's about ~billion x billion x billion Watts!)

Photons and neutrinos are produced in the core. Neutrinos escape directly. Photons (carrying heat energy) take considerably longer to escape.


RADIATIVE ZONE: So called because the energy is transported via RADIATION. Though it does so in a random walk. CONVECTIVE ZONE: Here, the heat energy moves forward via motion of hot material up, cool material down (churning, or boiling motion).




Stars are always losing energy to space (mostly as photons). Where does this energy come from?




Can they continue to lose energy for ever???




What happens when the star runs of out of fuel??