Where do main-sequence stars end up as they evolve?

Answer 1

A star just massive enough to burn helium will eject its outer layers as a planetary nebula and its core will form a white dwarf.
---
If it is using helium as fuel then it stopped being a main sequence star long long ago and if it has used up its helium and is now fusing carbon it has gone well outside the main sequence and is in the process of dying. All stars go through the process of being main sequence, so its a popular misnomer that a star has to be like the sun to be main sequence. The term refers to the time a star is converting hydrogen to helium, and any cycle after that changes what the star is called.

If you want to take the Sun as an example when it ends fusing hydrogen into helium, it will expand to a be a red giant about 250 times the size it is now and it will also lose about 30% of its mass.

Stars also continuously expel matter and winds into space, at the end of a stars life they either explode like a supernova (typical in stars much larger than the Sun), or each time a fuel source is used up, the star will expand until core temperatures and pressures rise enough to start a new fusion reaction. At this point, some of the outer layer is expelled and the star contracts to start its next life cycle. No star fuses elements heavier than iron.

Answer 2

Main-sequence stars eventually evolve into red giants or supergiants, depending on their initial mass. During this evolution, the star expands and increases in luminosity. As the star exhausts its nuclear fuel, it may eventually shed its outer layers and form a planetary nebula, leaving behind a remnant core known as a white dwarf, neutron star, or black hole.

Answer 3

It all depends on the mass of the star:

< 0.25 solar masses they will degenerate directly to a white dwarf.

>= 0.25 solar masses, the will evolve onto the giant branch as a red giant.

Answer 4

The main sequence star runs out if hydrogen "fuel" to use in fusion reactions in its core.

Then gravity causes the star to contract. Temperature and pressure increase in the core of the star. This enables new reactions to start, producing more energy.

If the star has enough mass, helium starts to be used as the fuel, together with hydrogen from outside the core.

Otherwise, hydrogen alone, from outside the core, can start to be used as fuel.

The star then expands, eventually becoming a giant star.

Answer 5

Most stars will end up as small WHITE DWARF stars, with all their nuclear fuel exhausted.

They still emit light because of energy derived from their gravitational collapse.

Eventually, after billions of years, they will become black dwarfs stars, emitting no visible light.

Stars with at least 8 times the Sun's mass end up as NEUTRON STARS or as

BLACK HOLES, after supernova explosions.

Answer 6

It fuses hydrogen into helium. The slight difference in mass is given off as heat.

Answer 7

The Sun will turn into a red giant, it's envelope almost touching the earth. After is "blows" it's outer envelope off as a planetary nebula the remains will become a white dwarf.

Answer 8

It becomes a white dwarf and leaves the main sequence.

Answer 9

Stars that are in nebulas and galaxys dont turn into nothing stars like the sun will do a planetary nebula and turn into a blackhole or neutron star.

Answer 10

See related question