The Sun

surface (photosphere): photons escape, sunspots, thin

center (core): nuclear fusion occurs, generating immense heat and energy that powers the sun

• nuclear fusion: only in the core where hydrogen atoms combine to form helium, releasing energy in the process (ex: 4 H to He + energy), very high temp and density needed forcing nuclear fusion

  • proton-proton chain (PP chain): a series of fusion reactions in which protons (hydrogen nuclei) fuse together to form helium, releasing positrons (anti-matter), neutrinos, and gamma rays, which are crucial for sustaining the energy output of the sun

radiative zone: the layer where energy produced in the core is transported outward through radiation, taking thousands of years for photons to reach the outer layers

• photon goes through random walk, direction is random, resulting in a lengthy process where the energy moves slowly through this zone before reaching the convective zone

convective zone: the outer layer of the sun's interior where energy is transported by convection, with hot plasma rising to the surface and cooler plasma sinking, creating a dynamic flow that contributes to solar activity

• temperature gradient: plasma rising and sinking creates a temperature gradient that drives convection currents, which play a crucial role in the transfer of energy to the sun's surface.

chromosphere: the layer above the photosphere, characterized by a reddish glow during solar eclipses; it plays a crucial role in solar phenomena such as solar flares and prominences

corona: the outermost layer of the sun's atmosphere, visible during a total solar eclipse, which extends millions of kilometers into space and has temperatures exceeding one million degrees Celsius, influencing solar wind and space weather