[Yugong series] February 2022 U3D full stack class 008 - build a galaxy scene

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Preface

Galaxy , It is also called the universe island , An operating system consisting of an exponentially large stellar system and interstellar dust . Galaxies are the basic unit of the universe . Refer to the Milky way , It's a containing star 、 Gas 、 Cosmic dust and dark matter , And big galaxies bound by gravity .

Typical galaxy , From dwarf galaxies with only tens of millions of stars , Even elliptical galaxies with trillions of stars , They all revolve around a mass center . In addition to individual stars and thin interstellar material , Most galaxies have a large number of multi star systems 、 Star clusters and various nebulae .
In the observable universe , The total number of galaxies may reach more than 100 billion . Most galaxies are between 1,000 to 10,0000 Second gap , The distance between each other is in the order of millions of seconds . Intergalactic space （ Exists in the space between galaxies ） Filled with extremely thin plasma , The average density is less than one atom per cubic meter . Most galaxies will be organized into larger groups , Become a galaxy group or cluster , And galaxy clusters converge into larger superclusters . These larger groups are often referred to as large-scale fiber structures , Distributed around the huge holes in the universe .

Since people know about galaxies, there have been many games about galaxies, such as ： Galaxy defense 、 The capsule 、 Wandering the earth, etc .