The sun produces energy through nuclear fusion.
In the process of nuclear fusion, two atomic nuclei combine, forming a larger, more massive nucleus and releasing energy. Within the sun, hydrogen atoms join together to form helium.
Such conditions exist in the sun’s core, or central region.
The sun’s interior consists of the core, the radiation zone, and the convection zone.
The sun’s energy is produced in its central core.
The radiation zone is a region of very tightly packed gas where energy is transferred mainly in the form of electromagnetic radiation.
The convection zone is the outer most layer of the sun’s interior. Hot gases rise from the bottom of the convection zone and gradually cool as they approach the top. Cooler gases sink, forming loops of gas that move energy toward the sun’s surface.
The sun’s atmosphere includes the photosphere, the chromosphere, and the corona.
The inner layer of the sun’s atmosphere is called the photosphere. The Greek word photo means “light,” so photosphere means the sphere that gives off visible light.
It is considered to be the sun’s surface layer.
This glow comes from the middle layer of the sun’s atmosphere, the chromosphere.
A fainter layer of the sun, which looks like a white halo around the sun, is called the corona, which means “crown” in Latin. The corona extends into space for millions of kilometers. It gradually thins into streams of electrically charged particles called the solar wind.
Features on or just above the sun’s surface include sunspots, prominences, and solar flares.
Sunspots are areas of gas on the sun’s surface that are cooler than the gases around them. Cooler gases don’t give off as much light as hotter gases, which is why sunspots look darker than the rest of the photosphere.
Huge, reddish loops of gas called prominences often link different parts of sunspot regions.
The energy heats gas on the sun to millions of degrees