Galaxies are broadly divided into star forming (gas rich) and quiescent (gas poor). The mechanism responsible for shutting down star formation in galaxies and transforming them into quiescent and passive galaxies has been unclear so far.
Dr. Yingjie Peng and Prof. Roberto Maiolino have led a study published in Nature in which they have analysed the stellar metallicities of thousands of nearby massve galaxies and from which they have inferred that the main mechanism responsible for quenching star formation in galaxies is “strangulation”, i.e. a process that halts the supply of gas to the galaxy.
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