Lecture 18: Star Birth and Death

  • In the Milky Way we observe stars as old as the Universe (13 billion years), stars like the sun with 4.5 billion years, star clusters a few million years old, and stars which are just forming.

  • Stars burn fuel to produce energy and shine --> they must evolve.

  • Any model of stellar formation and evolution must explain the H-R diagram (main-sequence, red giants, supergiants, white dwarfs).

    I. Star formation and pre-main-sequence evolution

    II. Evolution on the main-sequence

    III. Post main-sequence evolution and star death

    IV. Cosmic abundances of chemical elements