Turbulence in the interstellar medium
- 1SUPA, School of Physics & Astronomy, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9SS, UK
- 2Escola de Artes, Ciencias e Humanidades, Universidade de Sao Paulo, Rua Arlindo Bettio 1000, CEP 03828-000 Sao Paulo, Brazil
- 3LERMA/LRA, CNRS, Ecole Normale Supérieure and Observatoire de Paris, 24 rue Lhomond, 75231 Paris Cedex, France
- 4Observatoire de Paris, LESIA, CNRS, 92190 Meudon, France
- 5National Institute for Space Research (INPE) and World Institute for Space Environment Research (WISER), P.O. Box 515, 12227-010 São José dos Campos-SP, Brazil
- 6School of Mathematical Sciences, University of Adelaide, Adelaide, SA 5005, Australia
Abstract. Turbulence is ubiquitous in the insterstellar medium and plays a major role in several processes such as the formation of dense structures and stars, the stability of molecular clouds, the amplification of magnetic fields, and the re-acceleration and diffusion of cosmic rays. Despite its importance, interstellar turbulence, like turbulence in general, is far from being fully understood. In this review we present the basics of turbulence physics, focusing on the statistics of its structure and energy cascade. We explore the physics of compressible and incompressible turbulent flows, as well as magnetised cases. The most relevant observational techniques that provide quantitative insights into interstellar turbulence are also presented. We also discuss the main difficulties in developing a three-dimensional view of interstellar turbulence from these observations. Finally, we briefly present what the main sources of turbulence in the interstellar medium could be.