The Onset of Star Formation

  • Rudolf Kippenhahn
  • Alfred Weigert
  • Achim Weiss
Part of the Astronomy and Astrophysics Library book series (AAL)


Stars form out of interstellar matter. With modern telescopes and instruments this can nowadays be observed directly and in many phases of the formation process. Indeed a homogeneous cloud of compressible gas can become gravitationally unstable and collapse. In this section we shall deal with gravitational instability and then discuss some of its consequences. But before we do so it may be worth comparing this instability with those discussed in Chap. 25. For gravitational instability the inertia terms are important as well as heat exchange of the collapsing mass with its surroundings. But it is not a vibrational instability, since the classification scheme of Chap. 25 holds only if the free-fall time is much shorter than the timescale of thermal adjustment. As we will see later, just the opposite is the case here, during the earliest phases of star formation.


Star Formation Molecular Cloud Hydrostatic Equilibrium Gravitational Instability Emden Equation 
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  1. Bonner, W.B. (1956): Mon. Not. R. Astron. Soc. 116, 351Google Scholar
  2. Bromm, V., Larson, R.B. (2004): Ann. Rev. Astron. Astrophys. 42, 79Google Scholar
  3. Ebert, R. (1955): Z. Astrophy. 37, 217ADSzbMATHGoogle Scholar
  4. Low, C., Lynden-Bell, D. (1976): Mon. Not. R. Astron. Soc. 176, 367Google Scholar
  5. McKee, Ch.F., Ostriker, E.C. (2007): Ann. Rev. Astr. Astrophys. 45, 565Google Scholar
  6. Mac Low, M.-M., Klessen, R.S. (2004): Rev. Mod. Phys. 76, 125Google Scholar
  7. Mendoza, C., Seaton, M.J., Buerger, P., Bellorn, A., Melndez, M., Gonzlez, J., Rodrguez, L.S., Delahaye, F., Palacios, E., Pradhan, A.K., Zeippen, C.J. (2007): Mon. Not. R. Astron. Soc. 378, 1031Google Scholar
  8. Rees, M.J. (1976): Mon. Not. R. Astron. Soc. 176, 483Google Scholar
  9. Spitzer, L., Jr. (1968): Diffuse Matter in Space (Wiley, New York)Google Scholar
  10. Zinnecker, H., Yorke, H.W. (2007): Ann. Rev. Astron. Astrophys. 45, 481Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Rudolf Kippenhahn
    • 1
  • Alfred Weigert
    • 2
  • Achim Weiss
    • 3
  1. 1.GöttingenGermany
  2. 2.Universität HamburgHamburgGermany
  3. 3.Max-Planck-Institut für AstrophysikGarchingGermany

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