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"
Astronaut Kicks Lunar Field Goal
01/04/2019
Score three points for NASA. With time running out late in Apollo 15's mission to the Moon in 1971, Astronaut David Scott prepared to split the uprights and bring about yet another dramatic end-of-the-mission victory for NASA. Scott used a special lunar football designed for the rugged games held on the Moon. R1-D1, a predecessor to R2-D2, cheered from the sideline. Happy April Fools' Day from the folks at APOD. In reality, Astronaut Scott placed a drill that measured how temperature changed with lunar depth. The foreground device actually detected high-energy particles that escaped from the Sun. No Joke: NASA Plans to Return to the Moon in the Next Five Years