The Sun
The Sun is a yellow dwarf star (G2V), about 4.6 billion years old, and the dominant gravitational force in the Solar System. It has a diameter of roughly 1.4 million kilometers and contains around 99.8% of the Solar System’s mass. Nuclear fusion in its core converts hydrogen into helium, producing energy that warms the planets. Above the core lie the radiative and convective zones, followed by the visible photosphere (~5,500 °C), the chromosphere, and the much hotter corona (~2 million °C).
Source: science.nasa.gov
APODs including "The Sun"
Mars Red and Spica Blue
02/04/2014
A bright pair of sky objects will be visible together during the next few months. Mars will shine brightly in its familiar rusty hue as it reaches its brightest of 2014 next week. The reason that Mars appears so bright is that Earth and Mars are close to each other in their long orbits around the Sun. Spica, on the other hand, shines constantly as one of the brightest blue stars in the night sky. Pronounced "spy-kah", the blue-hued star has been visible throughout human history and the sounds that identify it today date back to ancient times. Pictured above, the planet and the star were photographed rising together toward the southeast after sunset last week through old oak trees in Sweden. Click Hyperspace: Random APOD Generator