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"
Gibbous vs Crescent
20/09/2025
rly risers around planet Earth have enjoyed a shining crescent Moon near brilliant Venus, close to the eastern horizon in recent morning twilight skies. And yesterday, on September 19, skygazers watching from some locations in Earth's northern hemisphere were also able to witness Venus, in the inner planet's waxing gibbous phase, pass behind the Moon's waning crescent. In fact, this telescopic snapshot was taken moments before that occultation of gibbous Venus by the crescent Moon began. The close-up view of the beautiful celestial alignment records Venus approaching part of the Moon's sunlit edge in clear daytime skies from the Swiss Alps. Tomorrow, the Sun will pass behind a New Moon. But to witness that partial solar eclipse on September 21, skygazers will need to watch from locations in planet Earth's southern hemisphere.