eso8712 — Press Release
Discovery of a Binary Quasar
15 July 1987: The discovery of what may be the first true binary quasar has been reported by a European-American team of astronomers using a combination of optical, spectral, and radio observations. The pairs of nearly identical quasars, separated by only 4.2 arcseconds projection on the sky, have a redshift of 1.345, corresponding to a distance of some 12 billion light-years from Earth (according to the standard cosmological distance scale) and are apparently associated with the radio source PKS 1145-071 in the constellation Crater [1].