The source of an incredibly bright X-ray, optical and radio signal appearing from halfway across the universe has been pinpointed to black hole 'jets' pointing straight at Earth.
The jets are caused by a supermassive black hole ripping apart a star 8.5 billion light years away, astronomers believe.
Huge amounts of debris travelling close to the speed of light were ejected into space as the distant sun got too close.
The beams, called 'relativistic jets', are pointing straight at Earth, researchers said. Their findings could shed new light on how supermassive black holes feed and grow.
The incredibly rare phenomenon is known as a tidal disruption event (TDE).
In our own Milky Way galaxy, this occurs up to once every 100,000 years.
Dr Michael Coughlin, co-lead author and from the University of Minnesota Twin Cities, said: "The last time scientists discovered one of these jets was well over a decade ago.
"The beams are known as relativistic jets – beams of matter travelling close to the speed of light – after destroying a star.
"From the data we have, we can estimate relativistic jets are launched in only 1% of these destructive events, making AT2022cmc an extremely rare occurrence.
"In fact, the luminous flash from the event is among the brightest ever observed."
An international team examined data collected in a survey named the The Zwicky Transient Facility and used a camera attached to the Samuel Oschin Telescope at the Palomar Observatory in California.
Co-author Dr Igor Andreoni, of the Nasa Goddard Space Flight Centre, said: "Our new search technique helps us to quickly identify rare cosmic events in the ZTF survey data.
"And since ZTF and upcoming larger surveys such as Vera Rubin's LSST scan the sky so frequently, we can now expect to uncover a wealth of rare, or previously undiscovered, cosmic events and study them in detail."
The burst of light was caused by 'spaghettification' of the star as gravity transformed it into a long, noodle-like string.
It sheds fresh light on supermassive black holes and their effect on surrounding matter.
The dead star got tightly wound like spaghetti around a fork to form a ball of hot plasma.
The black hole is millions or even billions of times the mass of our sun. There is one at the heart of the Milky Way.
The novel data-crunching method described in the journal Nature was equivalent to searching through a million pages of information every night.
It allowed the researchers to conduct a rapid analysis and identify the TDE with relativistic jets.
Follow-up observations that revealed an exceptionally bright event across the electromagnetic spectrum.
The black hole is at the centre of a galaxy that is not yet visible because the light from the jet streams outshone it.
Future observations with the Hubble or James Webb Space Telescopes may unveil the galaxy.
It is believed a rapid black hole spin may be one necessary ingredient for jet launching.
The idea brings researchers closer to understanding the physics of supermassive black holes at the centre of galaxies billions of light years away.
Only a couple of possible jetted TDEs were known previously, primarily discovered by gamma-ray space missions.
They detect the highest-energy forms of radiation produced by these jets. With their new method, astronomers can now search for such rare events in ground-based optical surveys.
Dr Andreoni said: "Astronomy is changing rapidly. More optical and infrared all-sky surveys are now active or will soon come online.
"Scientists can use the TDE as a model for what to look for and find more disruptive events from distant black holes.
"This means that more than ever, big data mining is an important tool to advance our knowledge of the universe."
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