Understanding the role of feedback from supermassive black holes in galaxy formation

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The Cold Dark Matter model for the formation and evolution of structure in the Universe successfully describes how galaxies and clusters of galaxies are spread throughout the cosmos.  However it fails to describe the basic properties of galaxies themselves.  Astronomers are beginning to realize that this failure is related to a key piece of missing physics: outflows of matter and energy from supermassive black holes in the nuclei of galaxies.  These outflows are difficult to model in part because there are few reliable measurements of the energy they release.  The best measurements have emerged from recent X-ray observations of galaxies and galaxy clusters.High resolution images taken with NASA's Chandra X-ray Observatory have revealed enormous voids in the rarefied atmospheres of hot gas surrounding galaxies and galaxy clusters.  The voids are typically 70,000 light years across, but can be up to 700,000 light years across (seven times the diameter of the Milky Way). They were created by powerful jets of charged particles gyrating along magnetic field lines at  relativistic speeds.  The jets themselves are created by supermassive black holes weighing as much as one billion Suns lurking in the nuclei of galaxies. The energy they release exceeds the power output of the Sun by up to ten trillion times, enough explosive power to drive outflows that displace between one billion and a trillion Suns worth of gas.  These outflows apparently play a fundamental role in the process of galaxy formation by limiting the sizes that galaxies and their attendant supermassive black holes can achieve.  This five year study of galaxies and clusters using a combination of X-ray, visual, ultraviolet, infrared, and radio telescopes will paint a vivid picture of how galaxies and their supermassive black holes form and evolve.  It will also delve deeply into the nature of the powerful and enigmatic radio jets emerging from the environs of supermassive black holes.