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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"

Full Moon, Full Mars

15/12/2022

Full Moon, Full Mars
Image Credit: Tomas Slovinsky / NASA APOD

On December 8 a full Moon and a full Mars were close, both bright and opposite the Sun in planet Earth's sky. In fact Mars was occulted, passing behind the Moon when viewed from some locations across Europe and North America. Seen from the city of Kosice in eastern Slovakia, the lunar occultation of Mars happened just before sunrise. The tantalizing spectacle was recorded in this telescopic timelapse sequence of exposures. It took about an hour for the Red Planet to disappear behind the lunar disk and then reappear as a warm-hued full Moon, the last full Moon of 2022, sank toward the western horizon. The next lunar occultation of bright planet Mars will be in the new year on January 3, when the Moon is in a waxing gibbous phase. Lunar occultations are only ever visible from a fraction of the Earth's surface, though. The January 3 occultation of Mars will be visible from parts of the South Atlantic, southern Africa, and the Indian Ocean.