Cosmic bumps on cosmic ripples
Friday, March 13, 2015 - 09:00
in Astronomy & Space
In 1969, the astrophysicists Rashid Sunyaev and Yakov Zel'dovich realized that the then recently discovered cosmic microwave background radiation (CMBR) would be distorted by hot cosmic gas. Hot electrons in the intergalactic medium preferentially scatter the light in one direction, causing a change in the brightness of the CMBR towards clusters of galaxies where electrons should be abundant. They showed that the effect would reveal the large-scale structure of the universe, the nature of the CMBR, cosmological parameters like the Hubble constant, and physical conditions in galaxy clusters.