Astronomers capture black hole gobbling up a star in a “hyper-feeding frenzy” - Ars Technica

1 year ago 53

Mmmmm, prima stuff! —

“It’s astir apt swallowing the prima astatine the complaint of fractional the wide of the Sun per year.”

Jennifer Ouellette - Nov 30, 2022 10:49 p.m. UTC

Illustration of a prima being spaghettified arsenic it’s sucked successful by a supermassive achromatic spread during a tidal disruption lawsuit (TDE).

Earlier this year, astronomers picked up an unusually agleam awesome successful the X-ray, optical, and vigor regimes, dubbed AT 2022cmc. They've present determined that the astir apt root of that awesome is simply a supermassive achromatic spread gobbling up a prima successful a "hyper-feeding frenzy," shooting retired jets of substance successful what's known arsenic a tidal disruption lawsuit (TDE). According to a caller paper published successful the diary Nature Astronomy, it's 1 for the grounds books: the furthest specified event yet detected astatine astir 8.5 cardinal light-years away.

The authors estimation the pitchy from this TDE is traveling astatine 99.99 percent the velocity of light, meaning the achromatic spread is truly chowing down connected its stellar repast. “It’s astir apt swallowing the prima astatine the complaint of fractional the wide of the Sun per year,” said co-author Dheeraj “DJ” Pasham of the University of Birmingham. “A batch of this tidal disruption happens aboriginal on, and we were capable to drawback this lawsuit close astatine the beginning, wrong 1 week of the achromatic spread starting to provender connected the star.”

As we've reported previously, it's a fashionable misconception that achromatic holes behave like cosmic vacuum cleaners, ravenously sucking up immoderate substance successful their surroundings. In reality, lone worldly that passes beyond the lawsuit horizon—including light—is swallowed up and can't escape, though achromatic holes are besides messy eaters. That means that portion of an object's substance is ejected successful a almighty jet.

If that entity is simply a star, the process of being shredded (or "spaghettified") by the almighty gravitational forces of a achromatic spread occurs extracurricular the lawsuit horizon, and portion of the star's archetypal wide is ejected violently outward. This, successful turn, tin signifier a rotating ringing of matter (aka an accretion disk) astir the achromatic spread that emits almighty X-rays and disposable light—and sometimes vigor waves. Physicist John Wheeler erstwhile described jetted TDEs arsenic "a conduit of toothpaste gripped choky astir its middle," specified that substance squirts retired either end. TDEs are 1 mode astronomers tin indirectly infer the beingness of a achromatic hole.

For instance, successful 2018, astronomers announced the archetypal nonstop image of the aftermath of a prima being shredded by a achromatic spread 20 cardinal times much monolithic than our Sun successful a brace of colliding galaxies called Arp 299, astir 150 cardinal light-years from Earth. A twelvemonth later, astronomers recorded the final decease throes of a prima being shredded by a supermassive achromatic hole, dubbed AT 2019qiz, which provided the archetypal nonstop grounds that outflowing state during disruption and accretion produces the almighty optical and vigor emissions antecedently observed. In January, astronomers spotted a 2nd campaigner TDE successful the vigor authorities (dubbed J1533+2727) successful archival information collected by the Very Large Array (VLA) scope successful New Mexico.

A achromatic spread devours a prima that has travel excessively close. In precise uncommon circumstances, this whitethorn besides effect successful jets moving astatine astir the velocity of airy that make airy observed by our telescopes astatine galore frequencies. AT2022cmc is the astir distant specified lawsuit recorded to date.

Astronomers archetypal spotted AT 2022cmc successful February and promptly turned aggregate telescopes operating crossed a wide scope of wavelengths toward the source. These included an X-ray scope connected committee the International Space Station called the Neutron Star Interior Composition Explorer (NICER). It was imaginable that the agleam signal—calculated to beryllium equivalent to the airy from 1,000 trillion suns—was a gamma ray burst from the illness of a monolithic star. But the information revealed a root 100 times much almighty than adjacent the strongest known gamma ray burst.

“Our spectrum told america that the root was hot: astir 30,000 degrees, which is emblematic for a TDE," said co-author Matt Nicholl of the University of Birmingham. "But we besides saw immoderate absorption of airy by the postulation wherever this lawsuit occurred. These absorption lines were highly shifted towards redder wavelengths, telling america that this postulation was overmuch further distant than we expected.”

Given the brightness of AT 2022cmc and its longer duration, astronomers concluded it indispensable beryllium powered by a supermassive achromatic hole. The X-ray information besides pointed to an "extreme accretion episode." That's erstwhile a whirlpool of debris forms arsenic the unfortunate prima falls into the achromatic hole. But the brightness was inactive a surprise, fixed however acold distant the root is from Earth. The authors property this to alleged "Doppler boosting," which occurs erstwhile the pitchy points straight toward Earth, overmuch similar however the dependable of a passing siren gets amplified. AT 2022cmc is lone the 4th Doppler-boosted TDE yet found; the past 1 was detected successful 2011.