Theory Interstellar Medium DIBs

'DIBs' comes for diffuse interstellar bands. They are large organic molecules the nature has remained unsolved for nearly a century as they are found in the interstellar medium in the galaxies. First DIBs were recorded in 1922 as astronomers later began systematic studies, starting in 1934. Molecules which give rise to DIBs are called 'carriers.' The answer about what those molecules are is a cornerstone to help explain how stars, planets and life form. Those mystery molecules have been found too in neighbouring Magellanic Clouds and in the Andromeda and the Triangulum galaxies

DIBs exist whatever the environment of the specific place of a galaxy where they are found, like high radiation levels, for example or varied amounts of metallicity, generally, those ingredients available to form stars and planets as DIBs however do not seem comfortable in the clouds of dense gas where stars are born. DIB-related suspect molecules, like three carbon atoms and two hydrogen atoms (C3H2), are all molecules which have in common of being organic, which is they are built largely from carbon. The top three carrier candidates are: one-dimensional chain-like molecules, two-dimensional PAHs, which often come up in studies of how planets formed, and three-dimensional compounds related to fullerenes, the soccer-ball-shaped molecules also known as buckyballs. In the Milky Way, when researchers find strong DIBs, they tend to find a lot of dust, too. This makes sense, because whenever there's more raw material available to make DIBs carriers, there's also more available to make dust. The current thinking is that such atoms or molecules are either locked up in fullerene cages or attached to the outside surface of those, or that carbon chains might dangle from other molecules or even from dust grains. One big difference between the Milky Way and Andromeda is the number of massive young stars. The Milky Way has more than Andromeda. Because those young stars generate a lot of UV radiation