Quasar doubles help to fix the Hubble constant

Henbest, Nigel
November 1991
New Scientist;11/16/91, Vol. 132 Issue 1795, p21
Reports that astronomers working at the European Southern Observatory in Chile are investigating double quasars that could help them find the precise value for the Hubble constant, which fixes the size and age of the Universe. Description of a quasar in the constellation of Virgo that appears as a very close double image; Details of how the quasar images could reduce the error in determining the Hubble constant.


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