37 Facts About Sun


The Sun radiates the energy mainly as light, ultraviolet, and infrared radiation, and is the most important source of energy for life on Earth.

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When hydrogen fusion in its core has diminished to the point at which the Sun is no longer in hydrostatic equilibrium, its core will undergo a marked increase in density and temperature while its outer layers expand, eventually transforming the Sun into a red giant.

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The astronomical symbol for the Sun is a circle with a center dot,.

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Sun is a G-type main-sequence star that constitutes about 99.

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Sun is by far the brightest object in the Earth's sky, with an apparent magnitude of -26.

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Sun is composed primarily of the chemical elements hydrogen and helium.

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The hydrogen and most of the helium in the Sun would have been produced by Big Bang nucleosynthesis in the first 20 minutes of the universe, and the heavier elements were produced by previous generations of stars before the Sun was formed, and spread into the interstellar medium during the final stages of stellar life and by events such as supernovae.

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Since the Sun formed, the main fusion process has involved fusing hydrogen into helium.

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The remainder of the Sun is heated by this energy as it is transferred outwards through many successive layers, finally to the solar photosphere where it escapes into space through radiation or advection .

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The large power output of the Sun is mainly due to the huge size and density of its core, with only a fairly small amount of power being generated per cubic metre.

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Theoretical models of the Sun's interior indicate a maximum power density, or energy production, of approximately 276.

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Thermal columns of the convection zone form an imprint on the surface of the Sun giving it a granular appearance called the solar granulation at the smallest scale and supergranulation at larger scales.

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The corona is the extended atmosphere of the Sun, which has a volume much larger than the volume enclosed by the Sun's photosphere.

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Ultraviolet light from the Sun has antiseptic properties and can be used to sanitize tools and water.

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For many years measurements of the number of neutrinos produced in the Sun were lower than theories predicted by a factor of 3.

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Sun has a stellar magnetic field that varies across its surface.

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Sun today is roughly halfway through the most stable part of its life.

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However, after hydrogen fusion in its core has stopped, the Sun will undergo dramatic changes, both internally and externally.

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Sun is about halfway through its main-sequence stage, during which nuclear fusion reactions in its core fuse hydrogen into helium.

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At this rate, the Sun has so far converted around 100 times the mass of Earth into energy, about 0.

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The core is therefore shrinking, allowing the outer layers of the Sun to move closer to the center, releasing gravitational potential energy.

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The Sun will spend around a billion years in the RGB and lose around a third of its mass.

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The orbits of the inner planets, including of the Earth, are similarly displaced by the same gravitational forces, so the movement of the Sun has little effect on the relative positions of the Earth and the Sun or on solar irradiance on the Earth as a function of time.

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Sun has been an object of veneration in many cultures throughout human history.

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Humanity's most fundamental understanding of the Sun is as the luminous disk in the sky, whose presence above the horizon causes day and whose absence causes night.

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In many prehistoric and ancient cultures, the Sun was thought to be a solar deity or other supernatural entity.

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The Sun has played an important part in many world religions, as described in a later section.

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Theory that the Sun is the center around which the planets orbit was first proposed by the ancient Greek Aristarchus of Samos in the 3rd century BC, and later adopted by Seleucus of Seleucia .

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In 1666, Isaac Newton observed the Sun's light using a prism, and showed that it is made up of light of many colors.

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Lord Kelvin suggested that the Sun is a gradually cooling liquid body that is radiating an internal store of heat.

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In 1920, Sir Arthur Eddington proposed that the pressures and temperatures at the core of the Sun could produce a nuclear fusion reaction that merged hydrogen into helium nuclei, resulting in a production of energy from the net change in mass.

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The preponderance of hydrogen in the Sun was confirmed in 1925 by Cecilia Payne using the ionization theory developed by Meghnad Saha.

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Worship of the Sun was central to civilizations such as the ancient Egyptians, the Inca of South America and the Aztecs of what is Mexico.

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In religions such as Hinduism, the Sun is still considered a god, he is known as Surya Dev.

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Ancient Sumerians believed that the Sun was Utu, the god of justice and twin brother of Inanna, the Queen of Heaven, who was identified as the planet Venus.

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From at least the Fourth Dynasty of Ancient Egypt, the Sun was worshipped as the god Ra, portrayed as a falcon-headed divinity surmounted by the solar disk, and surrounded by a serpent.

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In paganism, the Sun was a source of life, giving warmth and illumination to mankind.

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