Figure: The S106 star-forming region (Credit: NASA/ESA Hubble Space Telescope).

The interstellar medium is the diffuse gas and dust that fills the space between the stars. It is composed principally of hydrogen and helium gas and traces of silicate and carbon dust. Dense clouds of interstellar matter can collapse under their own self-gravity to form stars, while at the ends of their lives stars can return chemically enriched material to the interstellar medium in the form of stellar winds and supernova explosions. Atomic processes and stellar feedback control the energy balance in the interstellar medium. The physical conditions in interstellar material range from the extremely diffuse, very hot gas found in superbubbles, which is best observed at X-ray wavelengths, to the dense, cold molecular cloud material, which is observed at infrared and radio frequencies.

Current work in this area by IRyA researchers includes:

  • Formation and evolution of molecular clouds.
  • Molecular cloud structure and fragmentation.
  • Gravitational collapse and star formation.
  • Astrochemistry in the surroundings of young stellar objects.
  • Magnetohydrodynamics and thermodynamics of the ISM.
  • Turbulence in the diffuse ISM.
  • Stellar feedback.
  • Structure and dynamics of HII regions.
  • Superbubbles in the Large Magellanic Cloud.

Researchers who work directly in this field:


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