The celestial wonders never seem to cease!
Before the year is over, the scientists have yet another wonder to offer.
What’s that?
While investigating a mysterious radiation signal unlike any ever seen before, astronomers may have uncovered a rare pair of binary supermassive black holes with a truly monstrous appetite!
Read on to know more.
In a recent study, researchers observed something entirely unprecedented; which is a pair of supermassive black holes devouring an enormous gas cloud that’s unlike any celestial meal scientists have ever seen.
What is a supermassive black hole?
A supermassive black hole (SMBH) is a massive astronomical object that sits at the centre of most galaxies, with a mass that is hundreds of thousands to billions of times the mass of the Sun.
SMBHs are so dense and compact that they emit no light. They are gravitational giants, and the force of gravity increases as distance decreases. This means that objects orbiting a SMBH can stray into a region where the gravity is extremely strong.
SMBHs are thought to co-evolve with galaxies. When a SMBH consumes a large amount of matter, it can become bright enough to be seen across the cosmos, powering active galactic nuclei (AGN). AGN are enormous collections of stars that can include quasars and Seyfert galaxies.
Now, these cosmic titans with masses of 100,000 to billions of times the mass of the sun, are among the universe’s most fearsome phenomena. These celestial behemoths can consume entire stars and unleash torrents of powerful radiation visible across vast cosmic distances.
However, the new research witnessed two SMBHs gorging on nothing but an enormous gas cloud!
Ain’t that interesting!
The research:
This discovery, which has been made possible by a curious radiation signal, offers new insight into the behaviour of these cosmic giants and their relationship with the galaxies they inhabit.
According to Lorena Hernández-García, an astrophysicist at the Millennium Institute of Astrophysics and the University of Valparaíso in Chile and lead author of a new study on the ravenous black holes, as she told Live Science, “The light that is emitted from the system shows an oscillatory pattern that is repeated every 60 – 90 days, and this is the first time that this kind of variation is observed in an active galactic nucleus. This pattern is observed in the X-rays, ultraviolet and optical frequencies, making this system unique.”
What was the mysterious signal?
The signal, designated AT 2021hdr, was first detected in March 2021 by the Zwicky Transient Facility, a powerful ground-based optical survey. It originated from a galaxy known as 2MASX J21240027+3409114, located approximately 1 billion light-years away, in the northern constellation Cygnus.
At first, it was suspected that the signal might be linked to more familiar phenomena, such as a supernova or a tidal disruption event, which is when a black hole tears a star apart.
However, the signal exhibited a highly unusual brightness oscillation pattern not observed in such events. This intriguing anomaly prompted the research team to investigate the signal in greater depth.
Hernández-García explained, “We observed how the light of the system varies with time, for more than four years, using multiwavelength instrumentation. The study includes observations with the Swift satellite (X-rays and ultraviolet), Zwicky Transient Facility (optical), Very Long Baseline Array (radio), and optical telescopes in Spain, Mexico and India.”
These observations, spanning a wide range of wavelengths, confirmed that the earlier conclusion of the signal’s origin being unfamiliar. With no comparable signals to guide them, the researchers turned to theoretical models to solve the mystery and hypothesized that the radiation was produced by a pair of supermassive black holes consuming a massive cloud of galactic gas — a scenario previously explored through computer simulations.
Based on the simulation of the black holes’ interaction with each other and with a gas cloud, it was found that the signal the researchers studied fits well with the predictions of the computer model — if the supermassive black hole pair and gas cloud have particular properties.
The impact:
Although the AT 2021hdr signal fits neatly within the team’s hypothesis, additional observations of similar systems will be necessary to solidify their conclusions. Future data will help refine models of how supermassive black holes behave when consuming galactic gas.
Hernández-García explained, “We need to confirm the scenario that we are proposing, so we need to collect new data and perform simulations using these data in order to probe our hypothesis.”
If validated, the discovery could transform how astronomers study supermassive black holes by offering a new method to investigate their evolution and their role in shaping galaxies. These massive objects are closely linked to their host galaxies, and learning more about their feeding habits could provide fresh insight into galactic development.
Hernández-García furthered noted, “Finding binary supermassive black holes is a challenging task, but from the theoretical point of view it is expected to be present in many galaxy centres. The fact that we cannot resolve the two black holes with the available instrumentation imply that we need to find alternative techniques to detect them through other methods. Finding more like this will allow us to study how galaxies merge and evolve with time.”
This post was originally published on here
