XJcwolfyX wrote:How do stars become Red Giants?
Lifted shamelessly from Wikipedia:
"When the star exhausts the hydrogen fuel in its core, nuclear reactions in the core stop, so the core begins to contract due to its gravity. This heats a shell just outside the core, where hydrogen remains, initiating fusion of hydrogen to helium in the shell. The higher temperatures lead to increasing reaction rates, producing enough energy to increase the star's luminosity by a factor of 1,000–10,000. The outer layers of the star then expand greatly, beginning the red giant phase of the star's life. Due to the expansion of the outer layers of the star, the energy produced in the core of the star is spread over a much larger surface area, resulting in a lower surface temperature and a shift in the star's visible light output towards the red – hence red giant, even though the color usually is orange."
I think this is a pretty understandable explanation.
Proud alumnus of Mounds View High School Science Olympiad, Arden Hills, MN
Co-founder of the MIT Science Olympiad Invitational Tournament:
http://scioly.mit.edu/
Michigan State University Physics '21
