What are the main differences between the life cycle of a high mass and a low mass star?

1 Answer
Mar 15, 2016

The Rate of fuel consumption and the Final Stage.


There isn't much of a difference in the initial stages of Stellar Evolution, the only difference is the rate at which the fuel burns. Both, a low mass Star and a High mass Star will Start off with fusing hydrogen into Helium, though a high mass Star will burn it faster because of increased pressure and temperature in the core.

A second difference is the ability to create heavier elements. A high mass Star after burning hydrogen to Helium, Helium to Carbon will also burn Carbon into other heavier elements like Neon, Magnesium, Oxygen and some can even go all the way up to Iron, where the Nuclear Fusion eventually Stops. Low mass Stars on the other hand, one like our Sun will burn Hydrogen to Helium at a Slow rate, they will also be able to burn Helium into Carbon but then they won't be able to fuse Carbon any further as it requires immense temperatures and pressures in the core.

Third Difference is the fate of the Star, what it becomes after it has consumed all of it's Fuel, when the core cannot go any further. A low mass Star like our about less than 1.4 times the mass of the Sun will become a White Dwarf, a small extremely dense Star, about the Size of the Earth. Stars with higher masses about 1.4 to 2.8 times the mass of the Sun will have so much gravity that they will collapse even further than the white dwarf Stage until the collapse will be contained by the Neutrons formed inside the core due to extreme compression. This is called a Neutron Star and has a size of rougly 20km. An even higher mass star, even heavier than 2.8 solar masses will have so much gravity that even Neutron degeneracy pressure won't be enough to stop the core from collapsing into nothing, you will get a black Hole.