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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"

Two Worlds, Two Analemmas

Two Worlds, Two Analemmas

21/06/2025

Major Lunar Standstill 2024-2025

Major Lunar Standstill 2024-2025

20/06/2025

Two Worlds, One Sun

Two Worlds, One Sun

15/06/2025

Rainbow Airglow over the Azores

Rainbow Airglow over the Azores

03/06/2025

Afterimage Sunset

Afterimage Sunset

31/05/2025

Mars in the Loop

Mars in the Loop

30/05/2025

Curly Spiral Galaxy M63

Curly Spiral Galaxy M63

22/05/2025

International Space Station Crosses the Sun

International Space Station Crosses the Sun

21/05/2025

NGC 1360: The Robin's Egg Nebula

NGC 1360: The Robin's Egg Nebula

14/05/2025

Yogi and Friends in 3D

Yogi and Friends in 3D

10/05/2025

Planet Lines Across Water

Planet Lines Across Water

05/05/2025

Saturn's Rings Appear to Disappear

Saturn's Rings Appear to Disappear

29/04/2025