Fig8_8 Formation of a giant star

Fig8_8 Formation of a giant star

Fig. 8.8 . When a main-sequence star consumes the hydrogen in its core, the inside of the star contracts and heats up, causing the outside to expand and cool down. Hydrogen burning resumes in a shell that envelops the collapsing core. The center of the star eventually heats up to about 100 million K, which is hot enough to burn helium and stop the core collapse. A giant star has then been created with a luminosity of about 100 times that of the Sun and a radius of approximately 50 times the radius of the Sun.

Copyright 2010, Professor Kenneth R. Lang, Tufts University