What determines the lifetime of a main sequence star?

The lifetime of a main sequence star is proportional to its mass and inversely proportional to its luminosity, which determines the rate of fuel consumption. The lifespan of massive stars, the masses of which are many times the mass of the Sun, are several million years, and for stars similar to the Sun, they are billions of years.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.