Above: Supercomputer Simulations Explain the Formation of Galaxies and Quasars in the Universe. The distribution of dark matter in the universe on different scales. © Max Planck Institute for Astrophysics
Observations made by the Cosmic Origins Spectrograph, a $70 million instrument designed by the University of Colorado Boulder and installed on the Hubble Space Telescope, reveals the universe is ‘missing’ light.
“We still don’t know for sure what it is, but at least one thing we thought we knew about the present day universe isn’t true.”
Carnegie Institution for Science’s Juna Kollmeier, lead author of a new study on the missing light published in The Astrophysical Journal Letters, said:
“It’s as if you’re in a big, brightly lit room, but you look around and see only a few 40-watt lightbulbs. Where is all that light coming from? It’s missing from our census.”
The research team analyzed the tendrils of hydrogen that bridge the vast reaches of empty space between galaxies. When hydrogen atoms are struck by highly energetic ultraviolet light, they are transformed from electrically neutral atoms to charged ions.
The astronomers were surprised when they found far more hydrogen ions than could be explained with the known ultraviolet light in the universe, which comes primarily from quasars. The difference is a stunning 400 percent.
CU-Boulder’s Oppenheimer, said:
“The simulations fit the data beautifully in the early universe, and they fit the local data beautifully if we’re allowed to assume that this extra light is really there. It’s possible the simulations do not reflect reality, which by itself would be a surprise, because intergalactic hydrogen is the component of the universe that we think we understand the best.”
Co-author David Weinberg of Ohio State University, said:
“The great thing about a 400 percent discrepancy is that you know something is really wrong. We still don’t know for sure what it is, but at least one thing we thought we knew about the present day universe isn’t true.”