The Sun is an average star on the Orion Arm of the Milky Way galaxy and the closest star to Earth. It is a main sequence star roughly half way through its lifetime. Its mass provides over 99% of the total mass of the solar system.
At the center of our solar system is a star, the Sun. The Sun is an average-sized star about halfway through its life cycle. It is a near-perfect sphere of plasma that emits radiation due to nuclear fusion reactions taking place. Nearly three-quarters of the Sun’s mass is its main nuclear fuel, hydrogen. When the fusion reactions take place, two hydrogen nuclei combine together to form a helium atom. This reaction produces a large amount of energy.
The Sun is essential for life on Earth as it provides heat and light energy for green plants to photosynthesize. The Sun accounts for over 99% of the mass in the solar system. Our Sun is a main sequence star that has remained stable for roughly four billion years and will remain stable for about another five billion years. After five billion years, the Sun’s supplied of hydrogen will run out and the Sun will expand. It could expand to swallow the orbits of Mercury and Venus, it could even encompass the Earth. Even if it doesn’t reach our home planet, the increase on surface temperatures would make life on Earth impossible.
It is not an especially large star, there are many more like it. The Sun is a part of a larger body of stars known as a galaxy. Our galaxy is called the Milky Way, it is a group of billions of stars orbiting a supermassive black hole. The Sun provides a gravitational force which binds our solar system together; every planet, rock and dust that orbits it does so because of the forces associated with the Sun’s mass.
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