Assertion: quasar's redshift | /r/HasProperty | genuine
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Source sentences:
text: Eventually, starting from about the 1970s, many lines of evidence (including the first X-ray space observatories, knowledge of black holes and modern models of cosmology) gradually demonstrated that the quasar redshifts are genuine and due to the expansion of space, that quasars are in fact as powerful and as distant as Schmidt and some other astronomers had suggested, and that their energy source is matter from an accretion disc falling onto a supermassive black hole.