Layers & Composition of sun-Astronomy

Layers & Composition of sun-Astronomy

This chapter is about Layers & Composition of sun-Astronomy

Aurora Australis

southern lights; caused by solar wind

Aurora Borealis

northern lights, caused by solar wind


middle layer of sun’s atmosphere; visible during a total solar eclipse; called the color sphere

CoreAurora aus

sun’s interior) central region, produces enormous amounts of energy, in the process of nuclear fusion (hydrogen joining to form helium). High temperatures & pressure.


outer layer of sun’s atmosphere; visible during total solar eclipse; looks like a halo around the sun; extends into space for millions of km; gradually thins into thick streams of electrically charged particles called solar wind.


: inner layer of sun’s atmosphere; sphere that gives off visible light; gases here are thick; considered sun’s surface layer (note: sun doesn’t have a solid surface)


: huge reddish loops of gas; often link sunspots; possibly due to the sun’s magnetic field

Radiation Zone

(sun’s interior) next up from the core; middle layer; region of tightly packed gas; energy is transferred in form of electromagnetic radiation. Very dense region

Solar flares

: sudden bursts of energy in the form of fire that erupts on the sun’s surface; happens when sunspot loops connect and release huge amounts of magnetic energy.

Solar Wind

occurs in the corona; solar flares increases this; responsible for increase in number of magnetic particles reaching Earth’s atmosphere; create powerful electric currents that result in greenish, red or purple glow in Earth’s sky (called auroras); can also cause magnetic storms

Sun Features

: features on or just above the sun’s surface include sunspots, prominences and solar flares

Sun’s Atmosphere:

photosphere, chromospheres, corona

Sun’s Interior

core, radiation zone, convection zone


areas of gas on the sun’s surface; cooler than the gas around it; appear darker; helped prove sun rotates on its axis; 11 year cycle; most disappear in two weeks; form where magnetic field is strongest

Convection Zone

sun’s interior)top or outermost layer. Gases rise and cool; then sink, forming loops of gas that move energy towards sun’s surface. Generates sun’s magnetic field