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The Kerfuffle Over Non-Cosmological Quasar Redshifts

-- | September 7, 2014

Question: Some years ago I read an article that said (if I recall correctly) that there were quasars that seemed to be associated with galaxies (maybe in the center), but the quasar’s much larger red shifts implied that their distance was far more than the associated galaxies’ distances. Has this ever been resolved? — Bill

Answer: The research that you are referring to was done mainly by two astronomers, Halton Arp and Geoffrey Burbidge. They proposed, based on observations of seemingly associated nearby galaxies and purportedly distant quasars, that quasars were simply ejected matter from these galaxies. In fact, once large surveys of galaxies (such as the Sloan Digital Sky Survey), became available it was possible to better test this apparent correlation. In summary, Arp and Burbidge were wrong, their assertion due in fact to what astronomers call a “selection effect”. If you are interested in more details on this now historical discussion see the Galactic Interactions blog post on the subject.

Jeff Mangum

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