Basically, the same battle between gravity and pressure that formed our pizza-shaped Solar System repeats itself on a vastly larger scale, compressing a much larger region of gas into a pizza shape millions to trillions of times heavier than the Sun. This collapse turns out to be quite unstable, so it doesn’t lead to a solar system on steroids with a single mega-star surrounded by mega-planets. Instead, it fragments into countless smaller gas clouds that form separate solar systems: thus, a galaxy has been born. Our Solar System is one of hundreds of billions in one of these pizza-shaped
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But this woud imply a lot of interstellar gas in between where stars formed ? This explanation is missing something
