The sun’s energy comes from nuclear fusion reactions that take place in its core. This means that the hydrogen atoms fuse together to form helium atoms, releasing huge amounts of energy in the process. The sun’s core gets very hot because of these reactions, but because it is so big, it takes millions of years for this heat to reach the surface.
But how does this work? The sun is made up mostly of hydrogen, which has one electron orbiting its nucleus. When an electron absorbs energy, it jumps up to a higher orbital shell and if it absorbs enough energy, it can jump all the way to an orbit so far away from the nucleus that it becomes unstable and falls back down again (this process is called ionization). The problem for the sun is that it doesn’t have enough mass for its gravity to hold on to these outer electrons very long before they fall away again – so instead it uses nuclear fusion reactions between hydrogen atoms as fuel!
The sun does not have any solid surface like other stars we see in space, so it cannot be touched or seen directly by telescopes or cameras because there are no shadows or reflections like there are with planets and moons in our solar system.
The sun will continue to provide energy for life on Earth for billions of years to come. The amount of energy it produces is enough for all living things on Earth.