Answer: Nuclear fusion.
Explanation: The sun is a medium-sized star, its radius is 695.510 km and its mass is equivalent to that obtained by bringing together about 110 planets equal to Earth (6371 km is its radius).
It has six layers: The core, the radioactive zone, the convective zone, the photosphere, the chromosphere and the corona.
Magnetic field disruptions near active regions can generate strong explosions in the sun such as sun flashes and coronal mass ejections. The degree of complexity of the sun´s magnetic field increases and decreases with the course of each sunspot cycle.
Sir Arthur Eddington was the first to evaluate all the data and dared to conjecture that nuclear fusion, the process that creates heavy elements from the fusion of lighter ones, could be responsible for the great production of the sun´s energy; this process make the sun´s energy was taken for the earth and the planet get back to the sun recycled energy. The sun has a very large and complex magnetic field; the average magnetic field of the sun is approximately 1 Gauss, almost twice as strong as the average magnetic field of the Earth´s surface (approximately 0.5 Gauss). Because the surface of the sun is more than 12.000 times larger than the Earth, the overall influence of the sun´s magnetic field is immensely large.
