Molecular hydrogen formation, interstellar medium

General Aspects About Molecular Hydrogen Formation in the Interstellar Medium... 

Fullerene-Like Structures on Carbon Dust of the Interstellar Medium Their Role in Molecular Hydrogen Formation... 

In the laboratory, the study of the properties of pure polyynes and poly-cumulenes is inhibited because of their extreme reactivity with oxygen and the formation of cross linked chains. In space, refractory dust made of silicates or carbonaceous material are formed in the atmosphere of evolved stars and released into the interstellar medium (ISM). In dense molecular clouds ( Hydrogen > 10 cm, 10-20 K) atoms and molecules that... 

The cycle of birth and death of stars that is initiated by population III stars constantly increases the abundance of heavy elements in the interstellar medium, a crucial prerequisite for terrestrial (rocky) planet formation and subsequently for the origin of life (75). Metals dispersed in the interstellar gas or incorporated into micron-sized dust particles and molecules like CO and water, have the ability to cool the interstellar gas much more efficiently than molecular hydrogen does for population III stars. These elements and molecules are also excited through atomic and molecular collisions and their return to lower lying energy levels releases energy via far-infrared and sub-millimeter radiation below... 

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