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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"

Clouds and the Golden Moon

12/07/2025

Clouds and the Golden Moon
Image Credit: Alexsandro Mota / NASA APOD

As the Sun set, a bright Full Moon rose on July 10. Its golden light illuminates clouds drifting through southern hemisphere skies in this well-composed telephoto image from Conceição do Coité, Bahia, Brazil. The brightest lunar phase is captured here with both a short and long exposure. The two exposures were combined to reveal details of the lunar surface in bright moonlight and a subtle iridescence along the dramatically backlit cloudscape. Of course, July's Full Moon is a winter moon in the southern hemisphere. But in the north it's known to some as the Thunder Moon, likely a nod to the sounds of this northern summer month's typically stormy weather.