Throughout history, people have always believed that the sun's energy came from fire. They believed this because if their fire produces heat and energy, so does the sun, right? Wrong! The sun's energy, they realized less than 100 years ago, comes from mass on the surface resulting from nuclear fusion! Nuclear fusion occurs in the nuclei of the hydrogen atom to form more massive nuclei, which release a huge amount of energy. Process in Nuclear fusion that occurs in the sun occurs when two hydrogen nuclei collide and/or fuse. First, a proton's positive charge is neutralized and emits a particle called a positron, turning the proton into a neutron and transforming the original protons into a proton-neutron pair. Second, another proton combines with this proton-neutron pair to produce a nucleus composed of two protons and one neutron. Third, two nuclei made up of two protons and neutrons collide and/or fuse. Two protons are released during fusion. The remaining two protons and neutrons are fused together to form a helium nucleus. During each phase, energy is released. The energy released during the three phases of nuclear fusion causes the sun to shine and gives it a very high temperature. The scientist can't see the inside of the sun but, computer models have revealed what the invisible layers might look like. In the center of the sun is the plague. The core makes up 25% of the sun's total diameter of 1,390,000 km. the temperature of the sun's core is approximately 15,000,000 degrees Celsius. No liquid or solid can exist in the core due to the insanely high temperatures. The core, like the entire sun, is made up of ionized gas. The mass of the Sun is 300,000 times the mass of the Earth. Due to the large mass of the sun, the pressure from the sun... at the center of the paper... mineral pours into these areas. IN some places the magnetic field is 10 times stronger than in other places, because less energy is transferred, these regions of the photosphere are up to 3.00°C colder than the surrounding regions. Although they continue to shine brightly, these cooler areas of the sun appear to cause us to be darker than the areas around them. A large sunspot has a diameter of more than 100,000 km, which is many times the diameter of the earth. The sunspot cycle lasts about 11 years. A sunspot cycle begins when the number of sunspots is very low but begins to increase. Sunspots initially appear in clusters halfway between the equator and the sun's poles. The number of sunspots increases as the years pass until it peaks at 100 or more sunspots, then begins to decline to its minimum only to start its 11-year cycle all over again..