quasar environment tagged posts

Double or Nothing: Astronomers Rethink Quasar Environment

Stars indicate quasars and bright (faint) galaxies at the same epoch are shown as circles (dots). The galaxy overdensity with respect to the average density is shown by the contour. The pair members are associated with high density regions of galaxies. Credit: NAOJ

Stars indicate quasars and bright (faint) galaxies at the same epoch are shown as circles (dots). The galaxy overdensity with respect to the average density is shown by the contour. The pair members are associated with high density regions of galaxies. Credit: NAOJ

Astronomers have identified nearly 200 ‘protoclusters,’ the progenitors of galaxy clusters, in the early Universe, about 12 billion years ago, about 10X more than previously known. They also found that quasars don’t tend to reside in protoclusters; but if there is one quasar in a protocluster, there is likely a second nearby. This result raises doubts about the relation between protoclusters and quasars.

In the Universe, galaxies are not distributed uniformly...

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