![]() The quasar has a large-scale visible jet, which measures ~200 kilolight-years (60 kpc) long, having an apparent size of 23″. The mass of its central black hole has been measured to be 886 ± 187 million solar masses through broad emission-line reverberation mapping. Since the Sun's absolute magnitude is 4.83, it means that the quasar is over 4 trillion times more luminous than the Sun at visible wavelengths. It is also one of the most luminous quasars known, with an absolute magnitude of −26.7, meaning that if it were only as distant as Pollux (~10 parsecs) it would appear nearly as bright in the sky as the Sun. A luminosity distance of D L = 749 megaparsecs (2.4 gigalight-years) may be calculated from z. It is the optically brightest quasar in the sky from Earth ( m ~12.9), and one of the closest with a redshift, z, of 0.158. It was the first quasar ever to be identified. Optically brightest quasar, first spectrum of a quasarģC 273 is a quasar located in the constellation of Virgo. But now we have a bigger issue to solve.Quasar 3C 273 taken by Hubble Space Telescope Ģ.443 Gly (749 Mpc) (luminosity distance) We thought that Seyfert transformation was the major puzzle. It tells us that the theory is all wrong. Suvi Gezari, an associate professor of astronomer at UMD and a co-author of the paper describing the observations said “theory suggests “a quasar should take thousands of years to turn on, but these observations suggest that it can happen very quickly. Observing six of these transitions, all in relatively quiet LINER galaxies, suggests that we’ve identified a totally new class of active galactic nucleus.” ![]() “But we later found it was a previously dormant black hole undergoing a transition that astronomers call a ‘changing look,’ resulting in a bright quasar. “For one of the six objects, we first thought we had observed a tidal disruption event, which happens when a star passes too close to a supermassive black hole and gets shredded,” said Frederick. Astronomers have debated whether the light from LINER galaxies is produced primarily by star-forming regions outside the nucleus or weakly active black holes in their cores.įrederick and her colleagues observed six “mild-mannered” LINER galaxies with the Zwicky Transient Facility at Caltech’s Palomar Observatory in California as part of a project to learn more about what causes differences in the output of Seyfert galaxies, which all feature bright nuclei. In between those two extremes are low-ionisation nuclear emission-line region, or LINER, galaxies, which account for about one third of all nearby galaxies. Galaxies come in a variety of shapes, size and brightness, ranging from low-key “ordinary” star swarms to super-luminous active galaxies, or quasars, that host supermassive black holes at their cores and emit torrents of radiation as they consume surrounding gas and dust. The forces at play must be very extreme and very dramatic.” “It will take some work to understand what can disrupt a galaxy’s accretion structure and cause these changes on such short order. “These changes are taking place much more quickly than we can explain with current quasar theory. “It’s surprising that any galaxy can change its look on human time scales,” said Sara Frederick, a graduate student at the University of Maryland and lead author of a paper in The Astrophysical Journal. But astronomers have identified six previously mild-mannered galaxies that suddenly transformed into voracious quasars, erupting in feeding frenzies powered by supermassive black holes. Galaxies are such enormous structures that major changes occur over extreme timescales. ![]() Smartt (Queen’s University Belfast (left), NASA/JPL-Caltech (right) ![]() Astronomers have found normally mild-mannered LINER galaxies, left, in the process of transforming into voracious quasars as seen in the artist’s rendering at right.
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