It is very simple to determine the age of sun (really an age of fusion reaction start), you don't even have to know some complex math to do it.
It is like determining a time when you started a fire in fireplace looking over amounts of charcoal and wood you currently have.
There is a nuclear fusion reaction going on in the star. Lighter elements, starting from simpliest one - hydrogen, assembles into heavier elements. So it will be less hydrogen and more other elements as time pass. Current amount of elements could be determined by observing Sun spectrum. Initial composition could be estimated from interstellar gas composition that did not experience fusion reaction. That's all, no magic or anything murky behind that Sun age estimation. You don't have to believe in it, you could do all the observations and math by yourself.
its called a sunspot... its been happening on the sun for literally...
billions of years...
the sun is 4.5 billion years old... it has about that much left in its life time...
It is very simple to determine the age of sun (really an age of fusion reaction start), you don't even have to know some complex math to do it.
It is like determining a time when you started a fire in fireplace looking over amounts of charcoal and wood you currently have.
There is a nuclear fusion reaction going on in the star. Lighter elements, starting from simpliest one - hydrogen, assembles into heavier elements. So it will be less hydrogen and more other elements as time pass. Current amount of elements could be determined by observing Sun spectrum. Initial composition could be estimated from interstellar gas composition that did not experience fusion reaction. That's all, no magic or anything murky behind that Sun age estimation. You don't have to believe in it, you could do all the observations and math by yourself.