7. Star Formation

Learning Goals

• Describe the types and states of material that exist in the space between the stars and how this material is detected.
• Explain the conditions under which a cloud of gas can contract into a stellar system.
• Understand the role gravity and angular momentum play in the formation of stars and planets.
• List the steps in the evolution of a protostar.
• Describe the H-R track of a protostar as it evolves to main sequence.

Outline

  1. The interstellar medium fills the space between stars
    • The composition of the interstellar medium
    • Interstellar dust and its effects on light
    • Temperature and densities of interstellar gas
    • Regions of cool, dense gas.
  2. Molecular clouds are the cradles of star formation
    • Self-gravity int he molecular cloud
    • Molecular clouds fragment as they collapse
  3. Formation and evolution of protostars
    • A protostar forms
    • The evolving protostar
    • Brown dwarfs
  4. Evolution before the main sequence
    • The evolutionary track of an evolving star
    • Bipolar outflow
    • The influence of mass

Activities

  • Class notes
  • Read chapter 15
  • LT pair & share: Star formation and lifetimes (pg. 119)
  • ClassAction: ISM and Star Formation (lessons 1-7)
  • DVD: Nebula (with notes outline provided in class)

Online resources