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"
Apollo 15 Panorama
05/08/2016
On July 31, 1971, Apollo 15 astronauts Jim Irwin and Dave Scott deployed the first Lunar Roving Vehicle on the Moon. Using it to explore their Hadley-Apennine landing site they spent nearly three days on the Moon while Al Worden orbited above. This digitally stitched panorama shows Scott examining a boulder on the slope of 3.5 kilometer high Mons Hadley Delta to the left of their electric-powered, four-wheel drive vehicle. The sun at his back, Irwin casts the strong shadow to the rover's right. The panoramic view extends farther right to the sunward direction, over Hadley Rille and lunar terrain, revealed in harsh, unfiltered sunlight. In total, the rover traversed 28 kilometers (17 miles) on the lunar surface. The Apollo 15 mission returned about 76 kilograms of moon rocks to planet Earth.