The sun was born about 4.6 billion years ago. Many scientists think the sun and the rest of the solar system formed from a giant, rotating cloud of gas and dust known as the solar nebula. As the nebula collapsed because of its gravity, it spun faster and flattened into a disk. Most of the material was pulled towards the center to form the sun.
The sun and its atmosphere are divided into several zones and layers. The solar interior, from inside out, is made up of the core, radioactive zone and the convective zone. The solar atmosphere above that consists of the photo-sphere, chromosphere, a transition region and the corona. Beyond that is the solar wind, and outflow of gas from the corona.