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"
Jupiter and Venus from Earth
18/03/2012
It was visible around the world. The sunset conjunction of Jupiter and Venus was visible last week almost no matter where you lived on Earth. Anyone on the planet with a clear western horizon at sunset could see them. This week the two are still notable, even though Jupiter has sunk below the brighter Venus. And if you look higher in the sky you can see Mars as well. Pictured above, a creative photographer traveled away from the town lights of Szubin, Poland to image a near closest approach of the two planets almost a week ago. The bright planets were separated only by three degrees and his daughter striking a humorous pose. A faint red sunset still glowed in the background. Although this conjunction is drawing to a close, another conjunction between Venus and Jupiter will occur next May. Gallery: See more images of this planetary conjunction from around the world