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Updated: Aug 7, 2026

Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
The legacy and large-scale distribution of active galaxies
1Princeton University Observatory, Peyton Hall, Princeton, NJ 08544, USA. tremaine@astro.princeton.edu
Abstract:
If accretion onto massive black holes is the power source for active galaxies, then nearby galaxies should contain 'dead quasars': black holes that do not shine, either because they are starved for fuel or because they accrete with low radiative efficiency. This article briefly reviews the evidence that most inactive galaxies contain black holes at their centres, and how the local distribution of black holes is related to the population of active galaxies.
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