Last moments of the star swallowed by the black hole were seen for the first time

 In this portrayal of the artist, a star (foreground) is depicted as spaghetti being swallowed by a supermassive black hole (in the background) during the 'tidal distortion event'.

 Using telescopes from the European Southern Observatory (ESO) and other organizations around the world, astronomers have detected a rare burst of light emanating from a star torn apart by a supermassive black hole.  This phenomenon, known as the tidal disruption event, which takes place only 215 million light-years from Earth, is the closest flare ever recorded.  Scientists had the opportunity to work on the event in unprecedented detail.  The research was published today in the Monthly Notices of the Royal Astronomical Society.

 What is a Black Hole?

 Matt Nicholl, a lecturer at the University of Birmingham and research fellow of the Royal Astronomical Society, the lead author of the new study, says: “A black hole 'sucking' a nearby star sounds like science fiction.  But that's exactly what happens in a tidal disruption event. "

 However, these tidal distortion events are rare and not always easy to study, in which a star experiences a state called spagetisation when swallowed by a black hole.  Aiming ESO's Very Wide Telescope (VLT) and New Technology Telescope (NTT) to this new flash of light near a supermassive black hole last year, the research team analyzed in detail what happens when such a monster swallows a star.

 Scientists knew theoretically what should happen.  "When an unfortunate star orbits very close to a supermassive black hole in the center of the galaxy, the extremely high gravitational force of the black hole slices that star into thin streams of matter," explains Thomas Wevers, one of the study's authors.  As some of these thin threads of stellar matter fall into the black hole during the spagetization process, a bright flare of energy emerges that astronomers can detect.

 Although powerful and bright, astronomers have so far had trouble investigating this burst of light because it often has a veil of dust and debris in front of it.  Scientists have just shed light on the origin of this veil.

 "We found that when a black hole swallows a star, it can eject matter out strongly, and these substances block our vision," says Samantha Oates, of the University of Birmingham.  The reason for this situation is;  the resulting energy pushes the debris of the star outward as the black hole eats the star's matter

 The discovery was made possible by the discovery of the tidal disruption event AT2019qiz, which the research team was working on, shortly after the star disintegrated.  Kate Alexander, from Northwestern University in the US, says: “Because we caught this early, we could actually see this veil of dust and debris piling up.  The black hole was ejecting matter outward at speeds of up to 10,000 km per hour.  This unique event, which offers the opportunity to 'look behind the scenes', allowed us to identify the origin of the black hole and track in real time how it enveloped the black hole. "

 The research team made these observations of AT2019qiz, which is in a spiral galaxy in the constellation Eridanus, over a six-month period when the intensity of the flare increased and then disappeared.

 “In several observations made, emissions from this new tidal disruption event were detected very quickly after the star collapsed,” says Wevers.  "To see how this light is generated, we've just pointed the space telescope in that direction with a group of ground-based telescopes."

 In the following months, more than one observation of the event was made using the powerful devices X-shooter and EFOSC2 found in ESO's VLT and NTT telescopes in Chile.  Precise and comprehensive observations made with ultraviolet, optics, X-rays and radio waves have revealed for the first time a direct link between the material flowing out of the star and the bright glow generated by the star being engulfed by the black hole.  "These observations showed that the star was about the same mass as our Sun, and lost about half of its mass to this giant black hole, which weighs more than a million times," says Nicholl, a visiting researcher at Edinburgh University.

 The research is helping to better understand how matter behaves in the surrounding extraordinary gravitational environments and supermassive black holes.  The research team says the AT2019qiz could even serve as a resource for interpreting future observations of tidal disruption events.  ESO's Extremely Large Telescope (ELT), which is expected to operate within a decade, will enable researchers to detect faint and faster evolving tidal distortion events and further illuminate the mysteries of black hole physics.