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The Sun is the star at the center of the Solar System.It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light and infrared radiation with 10% at ultraviolet energies.
Taken on 20 October 1968 from Apollo 7. Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is scattered and filtered through Earth's atmosphere as daylight when the Sun is above the horizon.
Orbital period. ~230 million years [ 10 ] The Solar System[ d ] is the gravitationally bound system of the Sun and the objects that orbit it. [ 11 ] It was formed about 4.6 billion years ago when a dense region of a molecular cloud collapsed, forming the Sun and a protoplanetary disc.
Sun path, sometimes also called day arc, refers to the daily and seasonal arc -like path that the Sun appears to follow across the sky as the Earth rotates and orbits the Sun. The Sun's path affects the length of daytime experienced and amount of daylight received along a certain latitude during a given season.
The solar cycle, also known as the solar magnetic activity cycle, sunspot cycle, or Schwabe cycle, is a nearly periodic 11-year change in the Sun 's activity measured in terms of variations in the number of observed sunspots on the Sun's surface.
Sunrise seen over the Atlantic Ocean through cirrus clouds on the Jersey Shore at Spring Lake, New Jersey, U.S. Sunrise (or sunup) is the moment when the upper rim of the Sun appears on the horizon in the morning. [ 1 ] The term can also refer to the entire process of the solar disk crossing the horizon.
Contents. Formation and evolution of the Solar System. There is evidence that the formation of the Solar System began about 4.6 billion years ago with the gravitational collapse of a small part of a giant molecular cloud. [ 1 ] Most of the collapsing mass collected in the center, forming the Sun, while the rest flattened into a protoplanetary ...
Exposure of skin to ultraviolet radiation from sunlight presents both positive and negative health effects. On the positive side, UV exposure enables the synthesis of vitamin D3, which is essential for bone health [1] and potentially plays a role in inhibiting certain cancers. [2][3] While vitamin D can also be obtained through dietary ...