where this type of clouds are formed?
In the space between the star systems in a galaxy
Interstellar cloud
he matter and radiation that exists in the space between the star systems in a galaxy
where does the gas and dust to form stars originate from "molecular clouds" what is this quoted term means? A molecular cloud, sometimes called a stellar nursery, is a type of interstellar cloud, the density and size of which permit the formation of molecules, most commonly molecular hydrogen
wiki:7757761
Interstellar cloud [SEP] Introduction
An interstellar cloud is generally an accumulation of gas, plasma, and dust in our and other galaxies. Put differently, an interstellar cloud is a denser-than-average region of the interstellar medium, (ISM), the matter and radiation that exists in the space between the star systems in a galaxy. Depending on the density, size, and temperature of a given cloud, its hydrogen can be neutral, making an H I region; ionized, or plasma making it an H II region; or molecular, which are referred to simply as molecular clouds, or sometime dense clouds. Neutral and ionized clouds are sometimes also called "diffuse clouds".