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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

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Moon Shadow on Jupiter

27/04/2022

Moon Shadow on Jupiter
Image Credit: NASA Astronomy Picture of the Day

What is that large dark spot on Jupiter? It's the shadow of Ganymede, Jupiter's largest moon. When Jupiter's moons cross between the Jovian giant and the Sun, they created shadows just like when the Earth's moon crosses between the Earth and the Sun. Also like on Earth, if you were in a dark shadow on Jupiter, you would see a moon completely eclipse the Sun. Unlike on Earth, moon shadows occur most days on Jupiter -- what's more unusual is that a spacecraft was close enough to record one with a high-resolution image. That spacecraft, Juno, was passing so close to Jupiter in late February that nearby clouds and the dark eclipse shadow appear relatively large. Juno has made many discoveries about our Solar System's largest planet, including, recently, rapidly expanding circular auroras. Explore Your Universe: Random APOD Generator