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Why are black holes that massive?

Why are black holes that massive?



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Today known most massive star, R136a1 weighs approximately 256 times the mass of our sun, how did supermassive black holes, with a mass of 10 billion times the sun form?

I understand, that when a star becomes black hole, its density increases, but does its mass also grow?


Here comes positive feedback - if something is heavy it tends to attract more things so it is even heavier and heavier. At one point it will clean its surroundings. This is the process for those supermassive black holes to create. In middle of galaxies there is lot of stuff (stars) that can be "eaten" by these huge black holes. Plus they had a lot of time to do so.

EDIT (thanks for questioning the answer I was very sure with it but there are some problems):

As Rob Jeffries said, the mass could not be acquired this way (probably not all of it) because of radiation pressure: when stuff falls towards black hole in accretion disk there is lot of heat created which pushes the rest of gas away. See Eddington limit. https://en.wikipedia.org/wiki/Eddington_luminosity

So after checking some pages those are the theories I found: http://science.nasa.gov/astrophysics/focus-areas/black-holes/

"One possible mechanism for the formation of supermassive black holes involves a chain reaction of collisions of stars in compact star clusters that results in the buildup of extremely massive stars, which then collapse to form intermediate-mass black holes. The star clusters then sink to the center of the galaxy, where the intermediate-mass black holes merge to form a supermassive black hole."

Another source: http://astronomy.swin.edu.au/cosmos/S/Supermassive+Black+Hole

"Stellar black holes result from the collapse of massive stars, and some have suggested that supermassive black holes form out of the collapse of massive clouds of gas during the early stages of the formation of the galaxy. Another idea is that a stellar black hole consumes enormous amounts of material over millions of years, growing to supermassive black hole proportions. Yet another, is that a cluster of stellar black holes form and eventually merge into a supermassive black hole."


The mass of a object does not increase when it collapses into a black hole. So a supermassive black hole must have started off quite small, and then grown.

The formation and growth of supermassive black hole is not settled science. Supermassive black holes probably started as large stellar mass black holes (The very earliest stars could have been very large, and were almost entirely free of any heavier elements, and could have collapsed to form black holes with a mass of about 100 suns) The black holes then grew as more matter fell into them.

There is a strong correlation between the size of a SMBH and its galaxy. Its not clear why this is, but it suggests that the environment that drove galaxy growth, also contributed to the growth of the black hole.


There are two theories of how super massive black holes formed. One is that they started as several stellar massive black holes that fell into the center of galaxies (which were forming around them) and came together creating a super massive black hole we see now. Another theory is that they started as "Dark stars", which are theoretical stars held together by dark matter, which can be much larger than a normal star. When the dark star collapses upon its self, it became a super massive black hole.


Astronomy 1142 - Black Holes

Astronomy 1142, Black Holes, is a one-semester course on the nature, formation, and discovery of black holes in the universe. It is a General Education (GE) Physical Science course in the Natural Science category. The goals of courses in this category are for students to understand the principles, theories, and methods of modern science, the relationship between science and technology, the implications of scientific discoveries, and the potential of science and technology to address problems of the contemporary world.

Course Objectives

By the end of this course, students should successfully be able to:

  • Understand the basic facts, principles, theories, and methods of modern science.
  • Understand key events in the development of science and recognize that science is an evolving body of knowledge.
  • Describe the interdependence of scientific and technological developments.
  • Recognize social and philosophical implications of scientific discoveries and understand the potential of science and technology to address problems of the contemporary world.

Astronomy 1142 will meet these expected outcomes through these specific learning objectives:

  • Qualitatively understand Newton's and Einstein's theories of gravity, space, and time, the similarities and differences between them, and the senses in which Einstein's theory has superseded Newton's.
  • Understand how Einstein's theory leads to the prediction of the existence of black holes.
  • Understand the interplay between gravity, pressure, and nuclear energy generation in governing the life cycle of stars, and of how and why the deaths of massive stars are expected to lead to the formation of black holes.
  • Understand how astronomers discovered the rst empirical evidence for black holes and of how they have set out to demonstrate the existence of black holes as conclusively as possible.
  • Understand why supermassive black holes are thought to be the central engines of quasars, the most luminous objects in the cosmos, and of the observational methods that are used to study quasars and the dormant black holes they have left behind in the centers of galaxies.
  • Understand the ways that new observatories and new space missions currently under development might lead to deeper understanding of black holes.

This course attempts to convey a number of the facts that astronomers and astrophysicists have learned about these topics, to describe the outstanding scientific problems that are the focus of current research, to illustrate ways in which physical principles are used to understand the universe, and to show how scientific theories are developed and tested against observations.

Course Organization

This is a 3 credit hour course each week, there will be 3 hours of lecture with occasional take-home assignments designed to explore some topics in more detail. For Arts and Sciences students in a Bachelor of Arts program, this course meets the Arts and Sciences GE requirement of a natural sciences course without a laboratory component.

Course Catalog Description

The nature, formation, and discovery of black holes in the Universe.

Prerequisites: ACT Math Subscore of 22 or higher, or Math Placement Level R or better, or Math 1050 (075), or permission of instructor. Not open to students with credit for 142.

This course is available for EM credit. GE nat sci phys course. NS Admis Cond course.


The most ancient supermassive black hole is bafflingly big

A quasar is a supermassive black hole in the core of a galaxy, wrapped in a bright disk of material. The most distant quasar now known is J0313-1806 (illustrated), which dates back to when the universe was a mere 670 million years old.

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January 18, 2021 at 8:00 am

The most ancient black hole ever discovered is so big it defies explanation.

This active supermassive black hole, or quasar, boasts a mass of 1.6 billion suns and lies at the heart of a galaxy more than 13 billion light-years from Earth. The quasar, dubbed J0313-1806, dates back to when the universe was just 670 million years old, or about 5 percent of the universe’s current age. That makes J0313-1806 two times heavier and 20 million years older than the last record-holder for earliest known black hole (SN: 12/6/17).

Finding such a huge supermassive black hole so early in the universe’s history challenges astronomers’ understanding of how these cosmic beasts first formed, researchers reported January 12 at a virtual meeting of the American Astronomical Society and in a paper posted at arXiv.org on January 8.

Supermassive black holes are thought to grow from smaller seed black holes that gobble up matter. But astronomer Feige Wang of the University of Arizona and colleagues calculated that even if J0313-1806’s seed formed right after the first stars in the universe and grew as fast as possible, it would have needed a starting mass of at least 10,000 suns. The normal way seed black holes form — through the collapse of massive stars — can only make black holes up to a few thousand times as massive as the sun.

A gargantuan seed black hole may have formed through the direct collapse of vast amounts of primordial hydrogen gas, says study coauthor Xiaohui Fan, also an astronomer at the University of Arizona in Tucson. Or perhaps J0313-1806’s seed started out small, forming through stellar collapse, and black holes can grow a lot faster than scientists think. “Both possibilities exist, but neither is proven,” Fan says. “We have to look much earlier [in the universe] and look for much less massive black holes to see how these things grow.”

Questions or comments on this article? E-mail us at [email protected]

A version of this article appears in the February 13, 2021 issue of Science News.

Citations

F. Wang. A Luminous quasar at a redshift of 7.64. American Astronomical Society meeting. January 12, 2021.

F. Wang et al. A luminous quasar at redshift 7.642. arXiv:2101.03179. Posted January 8, 2021.

About Maria Temming

Maria Temming is the staff reporter for physical sciences, covering everything from chemistry to computer science and cosmology. She has bachelor's degrees in physics and English, and a master's in science writing.


Next Radio Telescope Proposed for 2030s

Astronomers are imagining the next generation Very Large Array (ngVLA) with 244, 59-foot (18-meter) dishes spread over 5,505 miles (8,860 km). The Very Large Array (VLA) was built in the 1970s with an array of 27 82-foot (25-meter) dishes arranged in a “Y” shape.

Next generation radio telescope arrays would have a ten-fold improvement in sensitivity compared to the VLA, as well as a 30X improvement in angular resolution, the ngVLA will enable large statistical studies of AGN feedback in action. The ngVLA will be able to image the dominant population of AGN, which typically host radio jets with sub-galactic extents, over a large cosmic volume.

The ngVLA will also operate over a much wider range of frequencies (1 to 116 GHz) compared to the VLA (1 to 50 GHz), it will also be able to capture information from the carbon monoxide molecule, which has a bright transition around 115 GHz. This molecule can be used to measure the content and conditions of a galaxy’s star-forming gas reservoir.

The ngVLA will directly measure the effects of radio-jet-driven AGN feedback on galaxy evolution by comparing the radio jet and cold gas properties in galaxies over a wide variety of galaxy masses, distances, and environments. The new information will be compared with large computer simulations and improve our understanding of black hole physics and the universe.

SOURCE – National Radio Astronomy Observatory

Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.

Known for identifying cutting edge technologies, he is currently a Co-Founder of a startup and fundraiser for high potential early-stage companies. He is the Head of Research for Allocations for deep technology investments and an Angel Investor at Space Angels.

A frequent speaker at corporations, he has been a TEDx speaker, a Singularity University speaker and guest at numerous interviews for radio and podcasts. He is open to public speaking and advising engagements.


The Youngest, Most Massive Black Hole Is A Puzzle For Astronomy

This is an artist's impression of the quasar 3C 279. This quasar, as illustrated here, has a mass of . [+] over 1 billion Suns and is located about 5 billion light years away. Even more distant quasars have been found, but have exceedingly high masses that challenge our conventional view of cosmology.

Out in the extreme distances of the Universe, the first quasars can be found.

HE0435-1223, located in the centre of this wide-field image, is among the five best lensed quasars . [+] discovered to date. The foreground galaxy creates four almost evenly distributed images of the distant quasar around it.

ESA/Hubble, NASA, Suyu et al.

Supermassive black holes at the centers of young galaxies accelerate matter to tremendous speeds, causing them to emit jets of radiation.

While distant host galaxies for quasars and active galactic nuclei can often be imaged in . [+] visible/infrared light, the jets themselves and the surrounding emission is best viewed in both the X-ray and the radio, as illustrated here for the galaxy Hercules A.

NASA, ESA, S. Baum and C. O'Dea (RIT), R. Perley and W. Cotton (NRAO/AUI/NSF), and the Hubble Heritage Team (STScI/AURA)

What we observe enables us to reconstruct the mass of the central black hole, and explore the ultra-distant Universe.

The farther away we look, the closer in time we're seeing towards the Big Bang. The newest . [+] record-holder for quasars comes from a time when the Universe was just 690 million years old.

Jinyi Yang, University of Arizona Reidar Hahn, Fermilab M. Newhouse NOAO/AURA/NSF

Recently, a new black hole, J1342+0928, was discovered to originate from 13.1 billion years ago: when the Universe was 690 million years old, just 5% of its current age.

As viewed with our most powerful telescopes, such as Hubble, advances in camera technology and . [+] imaging techniques have enabled us to better probe and understand the physics and properties of distant quasars, including their central black hole properties.

NASA and J. Bahcall (IAS) (L) NASA, A. Martel (JHU), H. Ford (JHU), M. Clampin (STScI), G. Hartig (STScI), G. Illingworth (UCO/Lick Observatory), the ACS Science Team and ESA (R)

It has a mass of 800 million Suns, an exceedingly high figure for such early times.

This artist's rendering shows a galaxy being cleared of interstellar gas, the building blocks of new . [+] stars. Winds driven by a central black hole are responsible for this, and may be at the heart of what's driving this active ultra-distant galaxy behind this newly discovered quasar.

Even if this black hole formed from the very first stars, it would have to accrete matter and grow at the maximum rate possible — the Eddington limit — to reach this size so rapidly.

The active galaxy IRAS F11119+3257 shows, when viewed up close, outflows that may be consistent with . [+] a major merger. Supermassive black holes may only be visible when they're 'turned on' by an active feeding mechanism, explaining why we can see these ultra-distant black holes at all.

NASA's Goddard Space Flight Center/SDSS/S. Veilleux

Fortunately, there are other ways to grow a supermassive black hole.

When new bursts of star formation occur, large numbers of massive stars are created.

The visible/near-IR photos from Hubble show a massive star, about 25 times the mass of the Sun, that . [+] has winked out of existence, with no supernova or other explanation. Direct collapse is the only reasonable candidate explanation.

These can either directly collapse or go supernova, creating large numbers of massive black holes which then merge and grow.

Simulations of various gas-rich processes, such as galaxy mergers, indicate that the formation of . [+] direct collapse black holes should be possible. A combination of direct collapse, supernovae, and merging stars and stellar remnants could produce a young black hole this massive.

L. Mayer et al. (2014), via https://arxiv.org/abs/1411.5683

Only 20 black holes this large should exist so early in the Universe.

An ultra-distant quasar showing plenty of evidence for a supermassive black hole at its center. How . [+] that black hole got so massive so quickly is a topic of contentious scientific debate, but may have an answer that fits within our standard theories.


The Youngest, Most Massive Black Hole Is A Puzzle For Astronomy

Out in the extreme distances of the Universe, the first quasars can be found.

Supermassive black holes at the centers of young galaxies accelerate matter to tremendous speeds, causing them to emit jets of radiation.

What we observe enables us to reconstruct the mass of the central black hole, and explore the ultra-distant Universe.

Recently, a new black hole, J1342+0928, was discovered to originate from 13.1 billion years ago: when the Universe was 690 million years old, just 5% of its current age.

It has a mass of 800 million Suns, an exceedingly high figure for such early times.

Even if this black hole formed from the very first stars, it would have to accrete matter and grow at the maximum rate possible — the Eddington limit — to reach this size so rapidly.

Fortunately, there are other ways to grow a supermassive black hole.

When new bursts of star formation occur, large numbers of massive stars are created.

These can either directly collapse or go supernova, creating large numbers of massive black holes which then merge and grow.

Only 20 black holes this large should exist so early in the Universe.

Is this a problem for cosmology? More data will decide.

Mostly Mute Monday tells the astronomical story of an object, phenomenon, or mystery in visuals, images, and no more than 200 words.


Early Universe’s Massive Black Holes Born in Rapidly-Growing Dark Matter Halos: Study

When the Universe was less than 1 billion years old, some of its stars turned into supermassive black holes. A key mystery in astronomy has been: why are there so many huge black holes in the early Universe? A new simulation-based study, published in the journal Nature, suggests that massive black holes thrive when galaxies form very quickly. The study also finds that these black holes are much more common in the Universe than previously thought.

A 30,000 light-year region from the Renaissance Simulation centered on a cluster of young galaxies that generate radiation (white) and metals (green) while heating the surrounding gas. A dark matter halo just outside this heated region forms three supermassive stars (inset) each over 1,000 times the mass of our Sun that will quickly collapse into massive black holes and eventually supermassive black holes over billions of years. Image credit: Advanced Visualization Lab, National Center for Supercomputing Applications.

Dark matter collapses into halos that are the gravitational glue for all galaxies.

Early rapid growth of these halos prevented the formation of stars that would have competed with black holes for gaseous matter flowing into the area.

“The key criteria for determining where massive black holes formed during the Universe’s infancy relates to the rapid growth of pre-galactic gas clouds that are the forerunners of all present-day galaxies, meaning that most supermassive black holes have a common origin forming in this newly discovered scenario,” said study lead author Dr. John Wise, a researcher at the Center for Relativistic Astrophysics in Georgia Tech’s School of Physics.

“In the study, we have uncovered a totally new mechanism that sparks the formation of massive black holes in particular dark matter halos,” he said.

“Instead of just considering radiation, we need to look at how quickly the halos grow. We don’t need that much physics to understand it — just how the dark matter is distributed and how gravity will affect that. Forming a massive black hole requires being in a rare region with an intense convergence of matter.”

The previously accepted paradigm was that massive black holes could only form when exposed to high levels of nearby radiation.

“Previous theories suggested this should only happen when the sites were exposed to high levels of star-formation killing radiation,” said study co-author Dr. John Regan, research fellow in the Centre for Astrophysics and Relativity in Dublin City University.

“As we delved deeper, we saw that these sites were undergoing a period of extremely rapid growth. That was the key.”

“The earlier theory relied on intense UV radiation from a nearby galaxy to inhibit the formation of stars in the black hole-forming halo,” said study co-author Dr. Michael Norman, director of the San Diego Supercomputer Center at the University of California, San Diego.

“While UV radiation is still a factor, our work has shown that it is not the dominant factor, at least in our simulations.”

The study was based on the Renaissance Simulation suite, a 70-terabyte data set created on the Blue Waters supercomputer between 2011 and 2014 to help scientists understand how the Universe evolved during its early years.

To learn more about specific regions where massive black holes were likely to develop, the team examined the simulation data and found ten specific dark matter halos that should have formed stars given their masses but only contained a dense gas cloud.

The scientists then re-simulated two of those halos — each about 2,400 light-years across — at much higher resolution to understand details of what was happening in them 270 million years after the Big Bang.

The improved resolution of the simulation done for two candidate regions allowed the researchers to see turbulence and the inflow of gas and clumps of matter forming as the black hole precursors began to condense and spin. Their growth rate was dramatic.

“Astronomers observe supermassive black holes that have grown to a billion solar masses in 800 million years. Doing that required an intense convergence of mass in that region. You would expect that in regions where galaxies were forming at very early times,” Dr. Wise said.

Another aspect of the research is that the halos that give birth to black holes may be more common than previously believed.

“An exciting component of this work is the discovery that these types of halos, though rare, may be common enough,” said Michigan State University’s Professor Brian O’Shea, co-author of the study.

“We predict that this scenario would happen enough to be the origin of the most massive black holes that are observed, both early in the Universe and in galaxies at the present day.”

John H. Wise et al. Formation of massive black holes in rapidly growing pre-galactic gas clouds. Nature, published online January 23, 2019 doi: 10.1038/s41586-019-0873-4


This Massive Black Hole Is Mysteriously Quiet, And Astronomers Don’t Know Why

Scientists have studied the closest, largest, brightest galaxies to Earth for centuries.

Messier 51, the Whirlpool Galaxy, is one of astronomy’s most spectacular objects.

This enormous, face-on galaxy was the first one ever to reveal its spiral structure.

The small object alongside it, the galaxy NGC 5195, is interacting and merging with the Whirlpool galaxy.

Such mergers trigger new waves of star formation, create grand spiral arms, and activate supermassive black holes.

Both galaxies pull on each other, funneling gas onto each central black hole.

This matter then accelerates and gets ejected along powerful jets, producing X-ray emissions.

Prior studies with NASA’s Chandra X-ray telescope showed fewer X-rays than expected.

Exploring higher energies, NuSTAR still showed the same missing X-ray problem.

Excessive emission isn’t present in these cores the galactic centers are even outshone by outlying neutron stars.

This is problematic, according to lead author Murray Brightman:

Galactic mergers are supposed to generate black hole growth, and the evidence of that would be strong emission of high-energy X-rays. But we’re not seeing that here.

These results imply black holes flicker on and off more rapidly than anticipated.

Further research is needed the mystery remains unsolved for now.

Mostly Mute Monday tells the astronomical story of an object or phenomenon in visuals, images, and no more than 200 words. Talk less smile more.


Black Holes Regulate Star Formation in Massive Galaxies

The centers of massive galaxies are among the most exotic regions in the universe.

They harbour supermassive black hole, with masses of at least one million, and reaching thousands of millions of times the mass of the Sun. These black holes can cause a great deal of matter to fall towards them, producing the emission of huge quantities of energy before they finally fall into the black hole. In addition during this period (the "active phase" of the galaxy, referred to as an AGN or Active Galactic Nucleus) matter is expelled from outside the black hole in the form of high velocity (relativistic) jets, which can produce violent shocks with the surrounding matter.

For some time it has been thought that all of this emission of radiation and particles, and the growth of the black hole itself, should influence the way in which these galaxies form stars, making this star formation more difficult. "This influence " explains the first author of the article, Ignacio Martín Navarro, who studied for his doctorate at the Instituto de Astrofísica de Canarias (IAC) and the Universidad de La Laguna (ULL) and who is at present a researcher at the University of California at Santa Cruz (US) and the Max Planck Institut für Astronomie (Heidelberg, Germany), "allows us to explain the observed relations such as that between the mass of the central black hole and the total stellar mass. In fact without this "feedback" the simulations of the formation and the evolution of massive galaxies fail completely, both in reproducing their properties and in the number of galaxies predicted with a given mass". However until now there has been no observational evidence in favour of this idea which has become increasingly well known and established.

"In this work", adds Ignacio, "we analyse the spectra of the centres of 74 galaxies using data from the Hobby-Eberly Telescope Massive Galaxy Survey with the aim of finding out how the rate of star formation in these systems ahs changed during their lifetimes (the "star formation history"). To do this we used codes which allow us to compare the observed spectra with those predicted by models of stellar evolution. In this way we can learn how many stars of different ages there are in each of the observed galaxies".

"As a result of this analysis", explains Tomás Ruiz Lara, a researcher at the IAC and one of the authors of the Nature article, "we can explore the different star formation histories in galaxies with black holes of different masses. Our findings suggest clearly that, in effect, supermassive central black holes can affect the formation of stars throughout the lifetime of the galaxy, and that this effect depends on their masses".

According to this analysis, galaxies with more massive black holes in their centres show a faster rate of initial star formation, which gives rise to a more massive back hole which then can slow down the star formation in the galaxy. On the contrary, this process is produced much more slowly in those stars which currently harbour less massive black holes, starting with a lower star formation efficiency. " To be specific", stresses Ruiz Lara, "we find that the galaxies with the most massive central back holes form the major part of their masses (95%) up to 4,000 million years before the galaxies with less massive central black holes. But at the same time, the more recent star formation (during the last 700 million years) is greater for galaxies with less massive black holes".

The fact that the mass of these black holes is related to the quantity of matter and energy emitted during their AGN phase (which was well known), taken together with the new results, confirm a simple scenario previously envisaged, which has been clearly strengthened thanks to this study. To form stars efficiently, cold gas and dust are needed. However the energy and the particles emitted from the centre of a galaxy during its AGN phase can heat the interstellar medium through which they pass, reducing the possibility of star formation. For higher emission (which implies for greater mass of the central black hole), lower will be the efficiency of the host galaxy in forming its stars. This gives a ready explanation of why galaxies with the most massive black holes suppress their initial star formation first, so that more recent star formation is not favoured.

These results published in Nature which have a key importance in modern astrophysics and have been sought with great intensity during the past 20 years, offer key observational evidence for widely accepted hypotheses which are basic for understanding how the most massive galaxies form and evolve.

Paper: Ignacio Martín-Navarro et al. "Black-hole regulated star formation in massive galaxies", Nature. doi:10.1038/nature24999


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