Astronomers were surprised to notice that a quite quasar named SDSS J1011+5442 changed dramatically over the last 12 years. First noticed in 2003, quasar SDSS J1011+5442 has possibly eaten out its own fill in the recent years. The research team from University of Washington used the spectrum measurements of the quasar to calculate various factors. The reading for year 2015 suggests that the hydrogen-alpha emission declined by a factor of 50.

The black hole is still there but the research team feels that it has swallowed the gas in its vicinity. As a black hole swallows superheated gas in its surroundings, it emits massive amounts of light and radio waves. Using the spectrum analysis of the black hole, the research team was able to ascertain the properties of gas being swallowed by it.

Research team member and UW astronomy graduate student John Ruan said, "The difference was stunning and unprecedented. The hydrogen-alpha emission dropped by a factor of 50 in less than 12 years, and the quasar now looks like a normal galaxy."

The quasar has been termed as “changing-look quasar” by astronomers as it has raised questions with its fast changing nature. Study lead author Jessie Runnoe, a postdoctoral researcher at Pennsylvania State University said, "This is the first time we've seen a quasar shut off this dramatically, this quickly."

The research paper has been published in the journal Monthly Notices of Royal Astronomical Society. The paper informed, “The team's conclusion is that the quasar has used up all the glowing-hot gas in its immediate vicinity, leading to a rapid drop in brightness.”

The quasar and data collected by University of Washington team was presented at 227th Meeting of the American Astronomical Society in Kissimmee, Florida.

The research team used the Sloan Digital Sky Survey (SDSS) for collection of data regarding the quasar. SDSS-IV is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS Collaboration including the Brazilian Participation Group, the Carnegie Institution for Science, Carnegie Mellon University, the Chilean Participation Group, the French Participation Group, Harvard-Smithsonian Center for Astrophysics, Instituto de Astrofisica de Canarias, The Johns Hopkins University, Kavli Institute for the Physics and Mathematics of the Universe (IPMU) / University of Tokyo, Lawrence Berkeley National Laboratory, Leibniz Institut fur Astrophysik Potsdam (AIP), Max-Planck-Institut fur Astronomie (MPIA Heidelberg).

The research paper said, “Before Runnoe, Ruan and their colleagues could come to this conclusion, they had to rule out two other possibilities. A thick layer of dust could have passed through the host galaxy, obscuring their view of the black hole at its center. But, they concluded that there is no way that any dust cloud could have moved fast enough to cause a 50-fold drop in brightness in just two years. Another possibility is that the bright quasar in 2003 was just a temporary flare caused by the black hole ripping apart a nearby star. While this possibility has been invoked in similar cases, it cannot to explain the fact that the changing-look quasar had been shining for many years before it turned off.”