Supermassive black holes in 'red geyser' galaxies cause galactic warming

Scientists have uncovered a new class of galaxies, called "red geysers," with supermassive black hole winds so hot and energetic that stars can't form. Over the last few billion years, a mysterious kind of "galactic warming" has caused many galaxies to change from a lively place where new stars formed every now and then to a quiet place devoid of fresh young stars. But the mechanism that produces this dramatic transformation and keeps galaxies quiet has been one of the biggest unsolved mysteries in galaxy evolution.
Red geysers are old galaxies hosting low-energy supermassive black holes which drive intense interstellar winds. These winds suppress star formation by heating up the ambient gas found in galaxies and preventing it from cooling and condensing into stars.

https://www.sciencedaily.com/releases/2016/05/160525132805.htm
Paper: http://www.nature.com/nature/journal/v533/n7604/full/nature18006.html