Interstellar Carbonaceous Dust and Its Formation Pathways: From an Experimental Astrochemistry Perspective

Carbon because of its electronic structure can formulate several types of bonds and allotropes. In the ranking of elements in the Universe, carbon is the fourth most abundant after H, He and O. To date, carbon signatures have been detected in different parts of the interstellar medium (ISM), circumstellar medium (CSM) and in our solar system. It is now evident that in the ISM, carbon is present in the form of gas, ice and dust phases. Almost a decade ago, astronomers were able to trace the signature of the largest carbonaceous molecule, fullerene in different parts of the ISM, including planetary nebula (PNe), reflection nebula, and in ionised hydrogen (HII) regions. This has led the growing international astrochemistry community to revisit the formation pathways of different carbon nanostructures under simulated interstellar conditions. The aim of this article is to review and summarise all the experiments relevant to the formation of interstellar carbonaceous dust performed by various groups across the globe.