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"
Roses are Red
14/02/2026
Roses are red, nebulas are too, and this Valentine's gift is a stunning view! Pictured is a loving look at the Rosette Nebula (NGC 2237): a cosmic bloom of bright young stars sitting atop a stem of glowing hot gas. The rose’s blue-white speckles are among the most luminous stars in the galaxy, with some burning millions of times brighter than the Sun. Their stellar winds sculpt the famed rose shape by pushing gas and dust away from the center. Though only a few million years old, these massive stars are already nearing the end of their lives, while dimmer stars embedded in the nebula will burn for billions of years to come. The vibrant red hue comes from hydrogen gas, ionized by the ultraviolet light from the young stars. The rose’s blue-white center is color-mapped to indicate the presence of similarly ionized oxygen. The Rosette Nebula reminds us of the beauty and transformation woven into the fabric of the universe.