structure of the Sun [2]
From the center to the periphery are the core, the radiation and convection zones, the photosphere, the chromosphere and the corona.
flare 
Violent projection of extremely hot gas into space, provoking polar auroras on Earth a few days later.
faculae 
Luminous region of the photosphere.
spicules 
A narrow jet of gas in the form of a plume observed in the solar chromosphere.
photosphere 
Visible surface of the Sun, with a temperature of 10,000°F.
corona 
The outermost layer of the solar atmosphere, visible in the form of a halo during a total eclipse; corona temperatures can reach 1,800,000°F.
prominence 
Gas that erupts from the chromosphere and solar corona, contrasting with the darkness of space.
convection zone 
Region where hot gas currents circulate between the hot regions of the core and the cool surface.
radiation zone 
Region where energy produced in the core cools before migrating in the form of light and heat.
core 
The innermost part of the Sun where hydrogen is converted into helium by nuclear fusion; core temperatures reach 27,000,000°F.
granulation 
Network of cells on the photosphere brought about by the convective movement of hot gas from the Sun’s interior.
sunspot 
A dark, slightly cooler zone of the photosphere where the magnetic field is more intense.
chromosphere 
The lowest level of the solar atmosphere, with a temperature of 18,000°F.