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The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy mainly as light and infrared radiation. It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometres (864,000 miles), or 109 times that of Earth, and its mass is about 330,000 times that of Earth. It accounts for about 99.86% of the total mass of the Solar System.
Roughly three quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron.The Sun is a G-type main-sequence star (G2V) based on its spectral class. As such, it is informally and not completely accurately referred to as a yellow dwarf (its light is closer to white than yellow). It formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center, whereas the rest flattened into an orbiting disk that became the Solar System. The central mass became so hot and dense that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process.
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Piura (Quechua: Piwra) is city in northwestern Peru located in the Sechura Desert on the Piura River. It is the capital of the Piura Region and the Piura Province. Its population was 484,475 as of 2017.
It was here that Spanish Conqueror Francisco Pizarro founded the third Spanish city in South America and first in Peru, San Miguel de Piura, in July 1532.
Hanoi (UK: ha-, hə-NOY or US: hah-NOY; Vietnamese: Hà Nội [hàː nôjˀ] (listen)) is the capital...
Dalhart is a city in Dallam and Hartley counties in the U.S. state of Texas, and the county seat...
Boiry-Notre-Dame is a commune in the Pas-de-Calais department in the Hauts-de-France region in...