Skip to main content

Astronomers discover black hole ripping a star apart inside a galactic collision. 'It is a peculiar event'

   

From :- Space.Com

By :- By  

Edited by :- Amal Udawatta

Image from the Legacy Survey DR10 of the AT 2022wtn field. The inset shows the transient that occurred in the nucleus of the interacting minor galaxy, indicated by the blue cross.
(Image credit: Legacy Surveys / D. Lang (Perimeter Institute) / INAF / F. Onori)

The brutal star-destroying tidal disruption event is only the second ever seen in interacting galaxies.

Astronomers have taken a detailed look at a rare and incredibly violent cosmic event resulting from an unfortunate star venturing too close to a supermassive black hole. The team behind the research hopes it could reveal more about how such events, dubbed "tidal disruption events" or "TDEs," influence the evolution of their host galaxies.

These brutal battles between stellar bodies and the immense gravity of black holes with masses millions or even billions of times that of the sun result in stars being shredded and fed to the black holes. This cosmic cannibalism causes blasts of light that can outshine the combined light of every star in the host galaxy of the TDE, alerting scientists to a gory stellar death.

This particular TDE has been designated AT 2022wtn, and occurred in a galaxy located around 700 million light-years away. This galaxy is in the early stages of merging with one of its galactic neighbors.

It is thought that the two galaxies in this merging system have already made a close pass to one other

Image from the Legacy Survey DR10 of the AT 2022wtn field. The inset shows the transient that occurred in the nucleus of the interacting minor galaxy, indicated by the blue cross. The tidal tails, the result of the gravitational interaction and merger between the two galaxies, are clearly visible. (Image credit: Legacy Surveys / D. Lang (Perimeter Institute) / INAF / F. Onori)

This represents just the second time that a TDE has been detected in interacting galaxies. That's despite a prevailing theory that the early stages of mergers create the kind of conditions that favor these brutal occurrences.

How a star became stellar spaghetti

AT 2022wtn was first brought to the attention of astronomers at the Zwicky Transient Facility (ZTF), with further investigation in wavelengths of light ranging from radio to infrared and even X-rays, which revealed its nature as a TDE. The astronomers were able to determine that the black hole involved in this TDE has a mass equal to around 1 million suns, while its stellar meal is a low-mass star.

However, despite clearly presenting itself as an example of a supermassive black hole ripping apart a star, there are some unusual aspects of AT 2022wtn that set it apart from other TDEs.

"It is a peculiar event. Its light curve is characterized by a plateau in the phase of maximum brightness, lasting about 30 days, accompanied by a sharp drop in temperature and a spectral sequence that shows the development of two emission lines corresponding to the wavelengths of helium and nitrogen," team leader and National Institute for Astrophysics (INAF) Francesca Onori said in a statement. "Something that we had never observed with such clarity."

A yellow swirl with a blue cross in its north-west region

A closer look at the tidal disruption event AT 2022wtn, which is comprised of a black hole ripping apart and devouring a star. (Image credit: Legacy Surveys / D. Lang (Perimeter Institute) / INAF / F. Onori)

Like all TDEs, AT 2022wtn would have begun when a doomed star's orbit brought it too close to the central supermassive black hole at the heart of its host galaxy.

This results in the immense gravitational influence of the black hole generating immense tidal forces within the star. These forces squash the star horizontally while stretching it vertically, a process colorfully known as "spaghettification."

Some of the resulting stellar wreckage winds around the destructive supermassive black hole like actual spaghetti around a fork, forming a whirling flattened cloud of plasma called an accretion disk.

a spiral of orange and pink light circling a black orb

A illustration of a tidal disruption event in which a star is devoured by a black hole first forming an accretion disk around the ravenous cosmic titan. (Image credit: ESA/C. Carreau)

Not all of the material from the wrecked star falls around the black hole and eventually into its maw, however. A great deal of stellar matter is blasted out as powerful, high-speed outflows or jets.

In the case of AT 2022wtn, these outflows created a short, bright radio emission from the TDE and extreme changes in the velocity of light-emitting elements around the event.

This also indicated that the star was completely destroyed as a result of this TDE and that, in addition to an accretion disk, the cosmic cannibalistic event created an expanding spherical "bubble" of expelled gas.

"We found clear traces of the dynamics of the surrounding material also in some emission lines which show characteristics compatible with a fast propagation towards the outside," Onori said. "Thanks to our monitoring campaign, we were able to propose an interpretation of the origin of the observed radiation: AT2022wtn gave rise to a rapid formation of the disk around the black hole and the subsequent expulsion of part of the stellar matter.

"This result is particularly relevant, since the source of visible light and the physical conditions of the region from which it comes, in TDEs, are still under study."

The team's research was published on May 23 in the journal Monthly Notices of the Royal Astronomical Society.





Labels:

Comments

Post a Comment

Popular posts from this blog

New Comet SWAN Now Visible in Small Scopes

     From :- Sky & Telescope  By :- Bob King  Edited by :- Amal Udawatta This spectacular image of Comet SWAN (C/2025 F2) was taken on April 6th and shows a bright, condensed coma 5′ across and dual ion tails. The longer one extends for 2° in PA 298° and the other 30′ in PA 303°. Details: 11"/ 2.2 RASA and QHY600 camera. Michael Jaeger Amateur astronomers have done it again — discovered a comet. Not by looking through a telescope but through close study of  publicly released, low-resolution images  taken by the  Solar Wind Anisotropies  (SWAN) camera on the orbiting  Solar and Heliospheric Observatory  (SOHO). On March 29th, Vladimir Bezugly of Ukraine was the first to report a moving object in SWAN photos taken the week prior. Michael Mattiazzo of Victoria, Australia, independently found "a pretty obvious comet" the same day using the same images, noting that the object was about 11th magnitude and appeared to be brightening. R...
Post a Comment
Read more

Who Was the Real Marilyn Monroe?

  From - Smithsonian Magazine, By -  Grant Wong Historian, University of South Carolina, Edited by - Vinuri Randhula  Silva, “Blonde,” a heavily fictionalized film by Andrew Dominik, explores the star’s life and legend in a narrative that’s equal parts glamorous and disturbing Marilyn Monroe’s  final interview  is a heartbreaker. Published in  Life  magazine on August 3, 1962—just a day before the  actress died  of a barbiturate overdose at age 36—it found Monroe reflecting on her celebrity status, alternatively thoughtful, frank and witty. “When you’re famous you kind of run into human nature in a raw kind of way,” she observed. “It stirs up envy, fame does. People you run into feel that, well, who is she—who is she, who does she think she is, Marilyn Monroe?” That same question—who was the real Monroe?—has sparked debate among  cinema scholars ,  cultural critics ,  historians ,  novelists ,  filmmakers  and th...
Post a Comment
Read more

Why did Homo sapiens outlast all other human species?

  From - Live Science By  Mindy Weisberger Edited by - Amal Udawatta Reproductions of skulls from a Neanderthal (left), Homo sapiens (middle) and Australopithecus afarensis (right)   (Image credit: WHPics, Paul Campbell, and Attie Gerber via Getty Images; collage by Marilyn Perkins) Modern humans ( Homo sapiens ) are the sole surviving representatives of the  human family tree , but we're the last sentence in an evolutionary story that began approximately 6 million years ago and spawned at least 18 species known collectively as hominins.  There were at least nine  Homo  species — including  H. sapiens  —  distributed around Africa, Europe and Asia by about 300,000 years ago, according to the Smithsonian's  National Museum of Nat ural History  in Washington, D.C. One by one, all except  H. sapiens  disappeared.  Neanderthals  and a  Homo  group known as the  Denisovans  lived alongside...
Post a Comment
Read more