What are the Main Sequence of stars?
The main sequence of stars are distinguished by the source of their energy. According to CSIRO “They are all undergoing fusion of hydrogen into helium within their cores. The rate at which they do this and the amount of fuel available depends upon the mass of the star. Mass is the key factor in determining the lifespan of a main sequence star, its size and its luminosity. Stars on the main sequence also appear to be unchanging for long periods of time. Any model of such stars must be able to account for their stability. The simple model of any main sequence star is of a dense gas/fluid in a state of hydrostatic equilibrium. The inward acting force, gravity, is balanced by outward acting forces of gas pressure and the radiation pressure. Apart from the extremely hot but tenuous corona , the pressure and temperature of stars basically increases as you approach the core”. The main sequence of the star essentially have a fixed size that is a function of their mass. The greater the mass the greater its gravitations pull inwards is. This in turn compresses the gas more.
How are stars alike and different from each other?
Stars are alike as they give off heat and light and they are made of hydrogen and helium. All stars are bigger than biggest planet. Each star spins and are sphere like. Stars are different due to their size and mass. They are also different due to their shape and spin patterns. They each have different colours and temperatures. According to National Geographic “There are many kinds of stars: they can be big, they can be small, they can look blue or green, they can have many planets around them or none at all, they could be very old and ready to explode at any moment into a supernova, or they could just calmly cool down into a dwarf star. There are too many kinds of stars to list, but here's one thing I can tell you: just like every human being, no two stars are exactly the same”.