Cosmic Reionization of Hydrogen and Helium

Cosmic Reionization of Hydrogen and Helium

Cosmic reionization is a period in the Universe history when it switched from being predominantly neutral to mostly ionized. We still haven’t quite pinned down the source(s) that caused this transition, but we have our suspicions. It could be quasars. It could be galaxies. Or could it be something else?

[Figure from universe-review.ca/F05-galaxy06.htm]

Stealing Hot Gas from Galaxies

Stealing Hot Gas from Galaxies

The evolution of a galaxy is strongly dependent upon the environment the galaxy lives in. Galaxies moving through galaxy groups and galaxy clusters can get stripped of their gas that would otherwise be used to form stars. Today’s astrobite discusses simulations of the stripping and removal of the hot, gaseous coronae that surround galaxies.