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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"

Flight Through the Orion Nebula in Infrared Light

07/07/2021

Video Credit: NASA Astronomy Picture of the Day

What would it look like to fly into the Orion Nebula? The exciting dynamic visualization of the Orion Nebula is based on real astronomical data and adept movie rendering techniques. Up close and personal with a famous stellar nursery normally seen from 1,500 light-years away, the digitally modeled representation based is based on infrared data from the Spitzer Space Telescope. The perspective moves along a valley over a light-year wide, in the wall of the region's giant molecular cloud. Orion's valley ends in a cavity carved by the energetic winds and radiation of the massive central stars of the Trapezium star cluster. The entire Orion Nebula spans about 40 light years and is located in the same spiral arm of our Galaxy as the Sun.