created: 20230720094834001 modified: 20230720095518349 title: Sun type: text/vnd.tiddlywiki tags: [[Solar System]] [img class=hero-image [Sun Image]] The Sun, also known as Sol, is a star at the center of our [[solar system|Solar System]]. It is a yellow star that gives off different types of energy such as infrared energy (heat), ultraviolet light, radio waves and light. It also gives off a stream of particles, which reaches [[Earth]] as "solar wind". The source of all this energy is nuclear fusion. Nuclear fusion is the reaction in the star which turns hydrogen into helium and makes huge amounts of energy. It is a nearly perfect ball of hot plasma. The Sun is a star like many others in our [[Milky Way]] galaxy. The Sun is a type of star called a G-type main-sequence star based on its spectral class. The Sun has existed for a little over 4.5 billion years. It is going to continue for at least as long again. The Sun is about a hundred times as wide as the Earth. It has a mass of 1.9891×1030 kg. This is 333,000 times the mass of the [[Earth]]. 1.3 million [[Earths|Earth]] can fit inside the Sun. The Sun fuses about 600 million tons of hydrogen into helium every second. The Sun is the main source of energy for the [[Earth]]. This energy is made deep inside the Sun in a process called nuclear fusion. Four hydrogen atoms are fused together to make one helium atom. Some of the leftover matter turns into energy. This is the same way energy is released in a hydrogen bomb.