The discovery that the new quasar resides in a primarily neutral universe places it solidly in this era, at the edge of cosmic dawn.ĭespite its young age, the quasar harbors a whopper of a black hole - 800 million times the mass of the sun.įor Fan, it is amazing to discover so massive a black hole so early in cosmic history. The first galaxies were appearing, and their energetic radiation had begun to ionize the surrounding intergalactic gas, illuminating and forever transforming the universe from neutral to ionized. The universe was rapidly changing at this time. The new quasar is spotted at a redshift of 7.54, when the universe was only 690 million years old, or 5 percent of its current age. "It is missing in very deep visible light images, with its light shifted completely into the infrared, and that tells us it is extremely far away." "The new object is so far away that it is undetectable in visible light," explains Xiaohui Fan, a Regents' Professor at the University of Arizona's Steward Observatory and a coauthor of the study. Astronomers can measure this speed by taking advantage of the Doppler effect: Much like the siren of an ambulance is heard at lower frequencies the faster it is speeding away from a pedestrian's ears, the light coming from a distant cosmic object is shifted toward longer and longer wavelengths, in other words, into the red visible light and all the way into the near-infrared and infrared. The latest discovery, by a team led by Eduardo Bañados (Carnegie Observatories) and published in the journal Nature, is a record-breaker: J1342+0928, the most distant quasar known.īecause the universe has been expanding since the Big Bang, the more distant a cosmic object lies from an Earth-based observer, the faster it speeds away. To understand when supermassive black holes first appeared, astronomers scan the skies for actively-feeding black holes (known as "quasars") from the universe’s distant past. While some - like the black hole at the center of our own Milky Way - live quiet lives, occasionally snacking on a star or two, others feed voraciously, consuming gas and stars and growing rapidly in mass. Supermassive black holes lurk at the centers of many galaxies. (Image: Robin Dienel, courtesy of the Carnegie Institution for Science) The quasar is growing in mass as it is fed by a swirling disk of hot gas and dust. An artist’s concept of the most distant supermassive black hole known.
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