What temperature range defines diffuse molecular clouds?

Diffuse molecular clouds, often referred to as dark clouds, are regions in space where gas and dust are concentrated, leading to star formation. The temperature range that characterizes these clouds is typically between 15 to 50 Kelvin.

This temperature range is significant because it allows for the presence of molecular hydrogen, which is a key component in the formation of stars and other structures in the galaxy. In these low-temperature conditions, the gas molecules are able to clump together more effectively due to reduced kinetic energy, promoting the formation of denser molecular structures.

Low temperatures also limit the amount of energy that can disrupt the formation of molecules, leading to the stability seen in these clouds. Higher temperature ranges would result in increased thermal motion, which would counteract the processes necessary for the coalescence of gas into denser regions, thereby inhibiting star formation. Thus, the 15 to 50 K temperature range is essential for the conditions conducive to star formation and the structure of diffuse molecular clouds.