Star formation takes place within natal clouds of dust and gas that absorb much of the emitted ultraviolet and optical radiation but which also block these regions from optical view. In recent decades, however, infrared space-based observatories like Herschel and Spitzer have revolutionized our understanding of obscured star formation in dusty galaxies because infrared light can penetrate the dust clouds to reveal the stars being formed. Herschel and Spitzer have discovered large numbers of very dusty, very red star-forming galaxies that are immensely luminous in the infrared (exceeding one trillion solar-luminosities) yet are not seen at shorter wavelengths. In fact, these dusty galaxies are responsible for most of the infrared background light in the cosmos. Some of these objects display the most extreme kinds of starbursts known, with star formation rates exceeding a thousand per year, but which are also exceedingly rare with on average only one of them in a volume of a few hundred thousand million cubic light-years.
Click here for original story, Ultrared, dusty star-forming galaxies in the early universe
Source: Phys.org