Active Galactic Nuclei (AGN)
Galaxies are not only affected by the environment that they live in, but also their inner monsters. Massive galaxies often host supermassive black holes that can make the center of the galaxy an active place.
I have done some research on mass outflows and fueling flows in Seyfert galaxies while I was working at Goddard Space Flight Center (NASA) as a visiting undergraduate student. Details on this work can be found in this paper.
More recenly, using data from GASP, a large MUSE survey of jellyfish galaxies, we discovered a link between intense ram-pressure stripping and AGN activity. Out results suggest that ram-pressure by by the intra-cluster medium not only strips gas from galaxies, but it also pushes some of the gas towards the central region, feeding the black hole. These results were published in (Poggianti, Jaffe et al. 2017, Nature). This ESO press release explains in simple terms our findings.
The figure below shows a schematic diagram of a ``unified'' radio loud AGN (Urry & Padovani 1995):
