The Sun is a star that comprises 99.8 percent of the total mass of the solar system, and it is made up of 92.1 percent hydrogen and 7.8 percent helium. It is almost a perfect sphere with a diameter of approximately 864,336 miles, which is more than 100 times that of the Earth.
The circumference of the Sun is 2,715,395.6 miles, and it has more than 2.3 trillion miles in surface area. It would take more than 1.3 million Earths to equal the total volume of the Sun. It is divided by scientists in six different regions: the core, the radiative zone, the convective zone, the photosphere, the chromosphere and the corona. According to NASA, parts of the corona can extend out more than 4 billion miles, which is beyond the orbit of Pluto. The temperature in the core region is about 27 million degrees Fahrenheit, and this is where hydrogen atoms are fused under the Sun's intense gravitational pressure. This is compared with a relatively cool average of 10,000 degrees Fahrenheit at its surface. The Sun has no solid surface to physically connect the different parts of the sphere. The material at the equator spins once every 25 Earth days, while the material at the poles rotates once every 36 Earth days.