Parts of the Sun
The core is not only the hottest part of the sun, but it is also the hottest part of our solar system. The core emcompasses 25 percent of the sun's radius. The core is 15 million degrees Kelvin, with pressures so high, they cause hydrogen atoms to undergo nuclear fusion.
The radiative zone is a section of solar interior between the innermost core and the outer convective zone. This zone generates energy through nuclear fusion which is sent outwards as electromagnetic radiation.
This part of the sun is made of plasma. It starts out as 5,700 degrees Celcius and gets hotter as you go down. This difference in temperature is what causes the plasma to rise and fall while being heated and cooling. This gives it the name convection zone.
The photosphere is the visible surface of the sun. Since the sun is a ball of gas, this is not a solid surface. The gas in this layer is 100 km thick. Here there are sunspots, faculae, and granuels.
This is the irregular layer above the photosphere. Its temperature rises from 6,000 to 20,000 degrees Celcius. The high temperatures cause the hydrogen to emit a reddish color. In this layer there are prominences, solar flares, and filament eruptions.
The corona is the sun's outermost layer, and even though it's the last layer, it's the hottest of them all. This features streamers, plumes, and loops. Its shape changes with the sunspot cycle.
This is an area on the surface of the sun (photosphere) that appears to be darker than the rest. It has a cycle that lasts about 11 years and is larger than Earth.
This is a large bright feature extending outwards from the sun. This extends out into the sun's outer layer of the atmosphere, the corona.
A solar flare is a sudden variation of brightness. This occurs when magnetic energy builds up so high it releases, therefore emmiting radiation.
On Earth, these are more commonly referred to as the Northern Lights. This occur because of energetic particles speeding out of the sun in solar winds due to giant explosions.