Life Cycle of Stars | GCSE Physics | Doodle Science скачать в хорошем качестве

Life Cycle of Stars | GCSE Physics | Doodle Science

Follow me!:   / doodlesci   Doodle Science teaches you high school physics in a less boring way in almost no time! GCSE Science Script: Stars initially form from clouds of dust and gas. The force of gravity makes the gas and dust spiral in together to form a protostar. As the gas and dust falls together, it gets hot. A star forms when it is hot enough to fuse hydrogen nuclei into to helium. The star then immediately enters a long stable period, where the heat created by the nuclear fusion provides an outward pressure to counteract the force of gravity pulling everything inwards. In this stable period it’s called a main sequence star and it lasts several billion years. Luckily for us our sun in about half way through it’s stable period. Eventually however, like everything, the star must die. It takes one of 2 courses, the boring way or the cool way. Stars that are about the same size as our sun tend to take the boring way out. When the hydrogen begins to run out they begin to fuse heavier elements all the way up to iron in its core. The star at this point swells into a red giant which is unstable and ejects it’s outer layer of dust and gas as a planetary nebula; leaving behind a hot dense solid core called a white dwarf. Told you it was boring. Stars much bigger than our sun such as Betelgeuse are big enough to take the much more interesting route. Once they run out of hydrogen they start to swell up too, into a red super giant. At this point they are making elements in their core up to iron but it’s when they explode in a supernova, that the heavier elements are formed that are found all over our planet. The exploding supernova throws out its outer layers of dust and gas into space leaving a very dense core called a neutron star or in some cases a black hole. So if stars are responsible for nearly all of the elements on the periodic table, I guess you could say this video was brought to you by stars.