At the heart of the Milky Way lies a supermassive black hole known as Sagittarius A, which has a mass four million times that of our Sun. Although some scientists call it a gentle giant due to its quiet nature, it has the potential to transform into a formidable force in the future. One question that is on everyone’s minds is what happens when a black hole goes from dormant to active.
Therefore, we are going to dedicate this article to tell you What happens when a black hole goes from dormant to active? and what studies are there on this subject.
What exactly is a black hole?
A black hole represents an area in space where the gravitational pull is so powerful that nothing, not even light, can break free from its control. This phenomenon It occurs when a massive star succumbs to its own weight during the final stages of its existence. Discover how a black hole forms.
The intense gravitational forces compress all the star's mass into an incredibly small space, resulting in an infinite density known as a singularity at the black hole's core.
The event horizon defines the outer boundary of a black hole, indicating the point of no return; Anything that crosses this threshold, including light, cannot escape. Black holes vary significantly in size, from tiny ones comparable to atoms to supermassive black holes that are millions or even billions of times the mass of our Sun.
Although black holes are not directly visible, we can identify their existence by examining their influence on nearby matter and the light surrounding them.
Nature of black holes
Researchers announced that they had witnessed an astonishing glow at the center of a different galaxy in real time, apparently caused by a supermassive black hole awakening from its slumber and beginning to consume surrounding matter. This is the first time this phenomenon has been observed in real time.
Telescopes both on the ground and in orbit were used to observe what is happening at the heart of a galaxy known as SDSS1335+0728, which is located approximately 360 million light-years from Earth in the constellation Virgo. A light-year represents the distance that light travels in a single year,which is equivalent to approximately 9,5 trillion kilometers.
Black holes are extraordinarily dense, possessing a gravitational pull so intense that not even light can break free. They vary widely in size, from the mass equivalent to a star to the colossal giants found at the centres of many galaxies, which can be millions or even billions of times more massive.
The supermassive black hole located in the galaxy SDSS1335+0728 has a mass of about a million times that of the Sun. The area around a supermassive black hole can be incredibly tumultuous, destroying stars and consuming any other matter that falls within its gravitational pull.
Researchers say a rotating disk of diffuse material appears to have developed around the supermassive black hole SDSS1335+0728, absorbing some of the surrounding matter. This disk, known as an accretion disk, emits energy at extremely high temperatures, occasionally exceeding the brightness of an entire galaxy.
Active galactic nucleus
A region as dense and vibrant as this, fueled by a supermassive black hole at the heart of a galaxy, is called an "active galactic nucleus."
These nuclei are distinguished by their emission of significant energy in a range of wavelengths spanning from radio waves to gamma rays. “They are considered to be among the most luminous objects in the universe,” explains astrophysicist Paula Sánchez Sáez, lead author of the study published in the journal Astronomy & Astrophysics and affiliated with the European Southern Observatory in Germany.
Sanchez commented: "Examining active galactic nuclei is essential to understanding galaxy development and the dynamics of supermassive black holes." For decades, the galaxy, which It spans approximately 52 thousand light-years in diameter and has a mass comparable to about 10 billion Sun-like stars., was observed without significant changes. However, in 2019, sudden alterations were noticed and since then, observations have shown an increase in luminosity in the galaxy's core.
What happens when a black hole goes from dormant to active
Astrophysicist Lorena Hernández García, a co-author of the study from the University of Valparaíso in Chile, noted that while supermassive black holes can occasionally emit massive jets of high-energy particles into space, no such jet has been observed in this case.
What could have triggered this supermassive black hole? “Right now, we’re not sure,” Sanchez said. Hernandez commented: “This could be a natural phenomenon of the galaxy. Over the course of its life, a galaxy experiences several phases of activity and inactivity. An event, such as a star plunging into a black hole, could trigger a galaxy to become active.
Researchers suggest that if the observations indicate something other than the beginning of an active galactic nucleus, it would mean an astrophysical event that has never been observed before. Located approximately 26.000 light-years from Earth, Sagittarius A raises the question: could it wake up unexpectedly?
Hernandez said a similar fate could await Sgr A, which is currently inactive. However, we are not in any immediate danger. In fact, if it were to become active, we would probably not notice any change due to our significant distance from the center.
How to know when a black hole is activated
Not all black holes are the mass-destroying or “cosmic vacuum cleaners” we commonly imagine. Most are dormant because they do not interact with dust or gas (or devour stars or planets), so they are not visible to observing instruments.
A black hole becomes active when it begins to consume matter around it. In this case, Dust and gas trapped by gravity will approach the event horizon and spiral inThe remaining material will form a ring around the black hole, raising its temperature by millions of degrees. These gravitational structures are visible to astronomers because the disk surrounding them emits infrared radiation, X-rays and radio waves due to tidal effects.
I hope that with this information you can learn more about what happens when a black hole goes from being inactive to active.