A typical star, as it gets older. This should happen to our Sun, eventually.
When I say "typical star" I mean apart from the very numerous "red dwarf" stars.
The biggest star - VY Canis Majoris IS in a red supergiant phase and will explode as a massive supernova.
Before a star becomes a red giant, it goes through the stage of being a main sequence star, where nuclear fusion in its core converts hydrogen into helium, releasing energy in the form of light and heat.
Not really. It is formed in nova and supernova explosions or when a red giant star goes into an asymptotic giant phase. The only other method is by radioactive decay of iodine, uranium and plutonium.
During the red giant phase, hydrogen fusion occurs in the shell surrounding the helium core. The core is no longer fusing hydrogen, as it has already converted most of its hydrogen into helium. This causes the outer layers of the star to expand and cool, leading to the red giant phase.
Interesting...I wonder who he/she was in his/her past life. Where will God create life after the sun goes into it's red giant phase? Earth will be history.
A blue giant star goes through multiple stages during its life cycle: formation from a collapsing nebula, main sequence where it fuses hydrogen into helium, red giant phase where it expands and fuses heavier elements, and finally, depending on its mass, it may end as a supernova or a black hole.
The stage where a star swells into a red giant is called the red giant phase, typically occurring when a star runs out of hydrogen fuel in its core and starts to fuse helium in its shell. During this phase, the star expands and cools, turning redder in color due to its lower surface temperature.
It will expand and become a red giant.
It will be, eventually, after it goes through a red giant phase and consumes all of the inner planets - probably including Earth. If Earth is still here when that happens, 5 or so billion years from now, there will be no life left.
After its main sequence phase, a star like the Sun will enter the red giant phase where it expands and becomes cooler. Subsequently, it may evolve into a planetary nebula and eventually form a white dwarf.
No. The Sun is a main-sequence star. It will not be a red giant for another 5 billion years.(see related link for an image of what the Sun would look like in its red giant phase
it affects the heat generated by the star because as the sun goes through it's life, it goes through stages and it heats up as the core of the star turns into carbon and it heats up to become a red giant, but after the star goes red giant, it will become a white dwarf some time later and then go out and become a black dwarf