A fog of long-wavelength infrared light could be produced by dusty, star-forming galaxies that have remained hidden — until now, that is.

Vast swarms of hidden galaxies may be secretly bathing the universe in a soft glow

Source: space
Source Link: https://www.space.com/the-universe/galaxies/vast-swarms-of-hidden-galaxies-may-be-secretly-bathing-the-universe-in-a-soft-glow