The turbulent interstellar medium

The gas in galaxies is typically seen to be moving at very rapid, even supersonic velocities, providing clear evidence that the medium is highly turbulent. Looking more closely at gas clouds in our own Milky Way, astronomers have similarly demonstrated using a variety of different observations that the interstellar medium is turbulent. Turbulence is a key physical parameter in the star formation process because, like the thermal pressure of warm gas, it counters the collapse of clouds into stars