Helium Reionization in the Early Universe

Helium Reionization in the Early Universe

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News release ID: STScI-2010-31
Release Date: Oct 7, 2010
Image Use: Copyright
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This ultraviolet-light data from the Hubble Space Telescope's Cosmic Origins Spectrograph shows strong helium II absorption and transmission lines from a quasar, identifying an era 11.7 to 11.3 billion years ago when electrons were stripped from primeval helium atoms – a process called reionization.

Active Galaxies/Quasars, Cosmology, Galaxies, Intergalactic Gas, Spectra


Shull et al., ApJ, 722: 1312-1324, October 20, 2010