Skip to main content Accessibility help
  • Print publication year: 2010
  • Online publication date: June 2012

3 - Origin of the elements



Several processes were responsible for producing the current inventory of elements in the cosmos. Hydrogen, helium, and some lithium were created in the Big Bang, a massive explosion that is thought to have produced the universe. Elements heavier than hydrogen and helium, known as metals in astronomy, were produced in stars by processes collectively called stellar nucleosynthesis. The chemical elements other than hydrogen and helium in our solar system are the result of nucleosynthesis that occurred in stars that lived and died before the solar system formed. These processes involve fusion of light elements into heavy elements, sometimes at modest rates as stars evolve and sometimes at furious rates in stellar explosions. Significant amounts of a few rare elements, such as lithium, beryllium, and boron, were created via spallation reactions, in which collisions between highly energetic cosmic rays (typically protons or helium ions) and atoms break up the heavier nuclides into lighter fragments. And, of course, some nuclides have been produced by decay of radioactive nuclides. In this chapter, we will review these processes and discuss the evolution of the elemental abundances with time in the universe and the galaxy.

In the beginning

The cosmological model that best explains the origin of the universe is the Big Bang. According to this model, the universe began at a finite time in the past and at a discrete point in space, expanded from a hot dense initial state of very small size, and continues to expand to this day.

Related content

Powered by UNSILO
Suggestions for further reading
Brush, S. G. (1987) Cooling spheres and accumulating lead: the history of attempts to date the Earth's formation. The Science Teacher, 54, 29–34. A summary by a leading science historian.
Busso, M., Gallino, R. and Wasserburg, G. J. (1999) Nucleosynthesis in asymptotic giant branch stars: relevance for galactic enrichment and solar system formation. Annual Reviews of Astronomy and Astrophysics, 37, 239–309. A good review of nucleosynthesis in low- and intermediate-mass stars.
Hawking, S. W. (1988) A Brief History of Time. New York, NY: Bantam Books, 198 pp. A readable but authoritative book about cosmology and the Big Bang written by one of the leading scientists in the field.
Herwig, F. (2005) Evolution of asymptotic giant branch stars. Annual Reviews of Astronomy and Astrophysics, 43, 435–479. An excellent discussion of the evolution of AGB stars.
Weinberg, S. (1993) The First Three Minutes. New York, NY: Basic Books, 191 pp. Nobel prize-winning physicist Weinberg discusses the very beginnings of the universe in this influential book. It is a bit more detailed and challenging than Hawking's book, but provides more detail about the Big Bang.
Alpher, R. A., Bethe, H. and Gamow, G. (1948) The origin of chemical elements. Physical Review, 73, 803–804.
Basu, S. and Rana, N. C. (1992) Multiplicity-corrected mass function of main-sequence stars in the solar neighborhood. Astrophysical Journal, 393, 373–384.
Burbidge, E. M., Burbidge, G. R., Fowler, W. A. and Hoyle, F. (1957) Synthesis of elements in stars. Reviews of Modern Physics, 29, 547–650.
Caughlan, G. R. and Fowler, W. A. (1988) Thermonuclear reaction rates V. Cosmic Data and Nuclear Data Tables, 40, 283–334.
Champaign, A. E. and Wiescher, M. (1992) Explosive hydrogen burning. Annual Reviews of Nuclear and Particle Science, 42, 39–76.
Dearborn, D. S. P. (1992) Diagnostics of stellar evolution: the oxygen isotopes. Physics Reports, 210, 367–382.
Kroupa, P. (2002) The initial mass function of stars: evidence for uniformity in variable systems. Science, 295, 82–91.
Qian, Y.-Z. and Woosley, S. E. (1996) Nucleosynthesis in neutrino-driven winds. I. The physical conditions. Astrophysical Journal, 471, 331–351.
Qian, Y.-Z. and Wasserburg, G. J. (2007) Where, oh where has the r-process gone? Physics Reports, 442, 237–268.
Rolfs, C. E. and Rodney, W. S (1988) Cauldrons in the Cosmos. Chicago: University of Chicago Press, 561 pp.
Timmes, F. X., Woosley, S. E. and Weaver, T. A. (1995) Galactic chemical evolution: hydrogen through zinc. Astrophysical Journal Supplement, 98, 617–658.