© X-ray (NASA/CXC/Durham U/D. Alexander et al.); Optical (NASA/ESA/STScI/IoA/S Chapman et al.); Lyman-alpha Optical (NAOJ/Subaru/Tohoku Univ./T.Hayashino et al.); Infrared (NASA/JPL-Caltech/Durham Univ./J.Geach et al.)Large, glowing blobs of hydrogen gas (yellow) in the early universe seem to be lit by galaxies boasting gluttonous supermassive black holes (blue)
Mysterious blobs of gas dotting the early universe seem to be lit by ravenous black holes at the hearts of massive galaxies, a new study suggests. Further study of the strange clouds could reveal how young galaxies regulate their meals to become the galaxies we see today.
For about a decade, astronomers have puzzled over the power source behind vast reservoirs of glowing hydrogen gas that can span about 500,000 light years across, several times the size of our own Milky Way. These Lyman-alpha "blobs" are named after a wavelength of light released when an electron loses energy in a hydrogen atom.
One idea was that the blobs might be the next meals of growing galaxies. In this scenario, the gas clouds would radiate energy as they were tugged inwards by gravity and cooled down.
But a new study suggests the clouds are actually lit by almost-full galaxies that prevent the gas from falling inwards. Here, supermassive black holes inside the galaxies are thought to be devouring their surroundings, spawning powerful outpourings of energy.