Star formation (Life Cycle of Stars)

Step 1 Nebula

The attractive force of gravity pulls the dust and gas together to form the structure of a protostar

Step 2 Protostar

As more particles collide and join the protostar, it gets bigger and bigger + force of gravity gets stronger + allows it to attract even more dust and gas + Gravity also squeezes the protostar itself, making it more dense + particles inside it collide with each other more often + raises temp.

Step 3 Main Sequence

When pressure & temp get high enough hydrogen nuclei start to fuse together to form helium nuclei through nuclear fusion + gives out lots of energy which keeps the core of the star hot as nuclear fusion powers the star → at this point this is an actual star ( a main sequence star)

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