Astronomy

A black “superhole” possibility?

A black “superhole” possibility?


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When matter crosses the event horizon, it is easy to imagine that matter is torn apart into their individual components by tidal wave effects. Atoms would be ripped apart eventually.

At one time, the particles will fall so deep into the gravity well, that a single particle would be touching both sides of the gravity well at the same time. At that moment, I choose to assume that the particle particle core may be spaghettified, but externally it will appear to be shrinking.

Knowing that spaghettification is dependent on the size of the object, as well as the difference in gravity on both sides, a shrinking particle may eventually become so small that the steepness of the gravity well is no longer a problem.

The particle continues to shrink forever. Over time, gravity between all the particles that have shrunk, will again start to take effect - and I imagine that that is what happened in the big bang.

So the cosmic inflation, could just as well be particle shrinking, as a result of all particles in our universe being within the same black superhole.

Taking this idea, we could look at our own universe and I guess we would expect to see certain effects such as accelerating cosmic expansion, perhaps a cosmic background radiation and we would expect our universe to end as a cold, dead place.

Is this a known theory or idea, and where can I find papers on it?


Let's say you have a rocket near a Schwarzschild black hole. Near the horizon, the thrust required to keep stationary goes to infinity; in this specific sense, the gravitational force becomes infinite at the horizon. If the rocket is hovering above the horizon, then the difference in gravitational forces becomes arbitrarily large near the horizon. This can tear it apart. However, an object falling into the black hole will also gain a velocity arbitrarily close to the speed of light (as measured by a stationary observer as it passes) as it gets closer to the horizon, meaning it will be length-contracted. It shrinks to zero size. As a result, the difference in 'gravitational force' across it is more complicated, and in fact remains finite.

Knowing that spaghettification is dependent on the size of the object, as well as the difference in gravity on both sides, a shrinking particle may eventually become so small that the steepness of the gravity well is no longer a problem.

A shrinking object tames the infinite 'gravitational force' and keeps the tidal forces finite. But the curvature is already defined in the limit of the size of the measurement probe tending to zero. (The static tidal forces correspond to six of the twenty independent curvature components, but let's not worry about that much.) So no, you can't 'get rid of curvature' by shrinking your particle/system/whatever. That's conceptually broken.

Is this a known theory or idea, and where can I find papers on it?

You would have to have a much clearer idea before that can be answered reasonably. I've skipped all the way to the end of your question because I haven't understood anything more of what you're trying to say.


There exists various theories, some stating that every black hole contains a new universe… In fact as a once very dense object, our universe could also be seen as a black hole itself!

About what matter's enthropy becomes, Hawking proposes that it stays on the event horizon as a holographic structure, also compared to some kind of electric hairs


Wandering Supermassive Black Hole Detected in Distant Spiral Galaxy

This image shows the Sb-type spiral galaxy SDSS J043703.67+245606.8. Image credit: Sloan Digital Sky Survey.

J0437+2456 is a Sb-type spiral galaxy located approximately 230 million light-years away in the constellation of Taurus.

First detected in 2018, the galaxy’s supermassive black hole has a mass of about three million times that of the Sun.

“We don’t expect the majority of supermassive black holes to be moving they’re usually content to just sit around,” said Dr. Dominic Pesce, an astronomer at the Harvard & Smithsonian Center for Astrophysics.

“They’re just so heavy that it’s tough to get them going. Consider how much more difficult it is to kick a bowling ball into motion than it is to kick a soccer ball — realizing that in this case, the ‘bowling ball’ is several million times the mass of our Sun. That’s going to require a pretty mighty kick.”

Using observations with the Arecibo and Gemini Observatories, Dr. Pesce and colleagues confirmed the initial detection.

They found that J0437+2456’s supermassive black hole is moving with a speed of about 177,000 kmh (110,000 mph). But what’s causing the motion is not known.

“We may be observing the aftermath of two supermassive black holes merging,” said Dr. Jim Condon, a radio astronomer at the National Radio Astronomy Observatory.

“The result of such a merger can cause the newborn black hole to recoil, and we may be watching it in the act of recoiling or as it settles down again.”

But there’s another, perhaps even more exciting possibility: the black hole may be part of a binary system.

“Despite every expectation that they really ought to be out there in some abundance, scientists have had a hard time identifying clear examples of binary supermassive black holes,” Dr. Pesce said.

“What we could be seeing in J0437+2456 is one of the black holes in such a pair, with the other remaining hidden to our radio observations because of its lack of maser emission.”

The team’s paper was published in the Astrophysical Journal.

Dominic W. Pesce et al. 2021. A Restless Supermassive Black Hole in the Galaxy J0437+2456. ApJ 909, 141 doi: 10.3847/1538-4357/abde3d


Science Is Not about Getting More &ldquoLikes&rdquo

Social media measures the success of an idea by how many &ldquolikes&rdquo it gets. Scientific success is measured by how close the idea is to the truth. In the physical sciences, the truth is synonymous with experimental evidence. One would therefore expect physicists to measure success by how well their ideas match data rather than by how popular these ideas are among their peers. Surprisingly, this naive expectation is not manifested throughout the current landscape of theoretical physics.

The mathematical constructions of supersymmetry, string theory, Hawking radiation, anti-de Sitter/conformal field theory (AdS/CFT) and the multiverse are currently considered irrefutable and self-evident by the mainstream of theoretical physics, even without experimental evidence to support them. In the words of a prominent physicist at a conference that I attended a few months ago: &ldquoThese ideas must be true even without experimental testimony in their favor, because thousands of physicists believe in them and it is difficult to imagine that such a large community of mathematically-gifted scientists would be wrong.&rdquo

Once a mainstream culture grows to this self-sustaining phase, it does not need external verification. The ideas it advocates are reasoned to be inherently correct based on their mathematical beauty, with experiments serving the optional role of narrowing down the wide range of possibilities allowed by the flexible mathematical framework. Past generations of theoretical physicists were less arrogant among the possibilities they contemplated was one that allowed their theories to be proven wrong by experimental data.

But the current self-sustained culture thrives in its own theoretical sauce, dismissing alternatives because they are getting fewer &ldquolikes.&rdquo When award or grant-allocation committees are populated by advocates of the popular paradigm, it could take centuries to correct a path that should not have been taken in the first place. Large enough groups can legitimize speculative concepts without adhering to Carl Sagan&rsquos statement &ldquoExtraordinary claims require extraordinary evidence.&rdquo

To his I would add the basic lesson from Galileo Galilei that experimentation is crucial because extraordinary groupthink leads to extraordinary ignorance. Before Galileo&rsquos observations, it was popular to construct beautiful abstract frameworks on the assumptions that heavy objects fall faster than light objects under gravity and that the sun revolves around the Earth.

Is there anything new and alarming about the self-sustaining culture of some current physicists or was it always around, even after Galileo? My personal impression is that half a century ago, theoretical physicists were far more disposed to the concept of experimental vindication. But right now, if we double down on supersymmetry as being just around the corner when the Large Hadron Collider did not find evidence for it if we insist that Hawking radiation must exist despite the paradox that is spells between Einstein&rsquos general relativity and the fundamental principle of no information loss in quantum mechanics if we posit that the multiverse must exist, and anything that can happen will happen in it an infinite number of times&mdashwithout evidence to support this notion&mdashthen we are betraying the trademark of physics as an effort to describe the reality we live in.

After all, when I consider theoretically all possible amounts of money that I could have had in my bank account, I can get very excited. In particular, there is this attractive possibility that I am a billionaire. But going to an automated teller machine (ATM) and finding how much money I actually have, introduces a sobering tone to my spending habits. Getting data and comparing them to our theoretical ideas provides a reality check that we are not hallucinating or engaged in wishful thinking.

Even though I never tried this experience myself, I can imagine that avoiding feedback from experimental data must be similar to being on drugs. Based on the reports from those who had the experience, &ldquoyou are floating in constructions of your imagination and feeling happy.&rdquo A group of dreamers can feel happier together by sharing experiences and supporting each other.

Yet this activity misses the central point. Physics is not supposed to be a recreational activity that makes us feel good about ourselves. History teaches us that groups of humans can feel happy in the company of each other while advocating the wrong ideas. Science is a learning experience about nature that holds the potential of showing us wrong, irrespective of our popularity status on Twitter. Physics is a dialogue with nature, not a monologue. We are supposed to have skin in the game and make testable predictions.

Nevertheless, there are some physicists who even advocate the hypothesis that we might be living in a computer simulation. Here again, the appropriate response is to be guided by evidence. This proposal should gain traction only if we notice pixels in spacetime as we see on a computer screen or if we detect a bug indicating that the simulation had crashed. So far, reality appears very real to me. Perhaps this is because, unlike some advocates of this idea I have to check the balance in my bank account in order to avoid the consequences of acting irresponsibly.

Social pressure does not only fashion popular speculations in the realm of theory, but also limits the empirical exploration of far less speculative notions with instruments that we readily have. For example, the search for technological signatures of civilizations on exoplanets&mdashin the form of industrial pollution, artificial lights or heat, photovoltaic cells, structural artifacts or artificial satellites&mdashcould have been conducted with far more rigor if not for the reluctance of the mainstream to pursue this task. The related prejudice and peer pressure echo the refusal of some philosophers to look through Galileo&rsquos telescope.

How can physics recover its traditional humility with respect to evidence in the age of social media? The path forward is simple: priority should be given to gathering experimental data and ruling out theoretical ideas. There is nothing more humbling than being guided by data. Rather than spending full careers going down mathematical alleys that might be declared irrelevant by future generations of physicists, it would be prudent for young scientists to focus on those areas of research where the value of ideas can be tested and cashed during their lifetime.

Without experimenting at a nearby ATM, we run the risk of discovering one day that we are bankrupt. And the speculative notion that in some parts of the multiverse there might be a wealthier version of ourselves will not save our skin in this one reality to which we are held accountable.

The views expressed are those of the author(s) and are not necessarily those of Scientific American.


ANN ARBOR—A carbon nanotube coating developed at the University of Michigan acts as a “magic black cloth” that conceals an object’s three-dimensional geometry and makes it look like a flat black sheet.

The 70-micron coating, or carbon nanotube carpet, is about half the thickness of a sheet of paper. It absorbs 99.9 percent of the light that hits it, researchers say.

“You could use it to completely hide any 3D attributes of an object,” said Jay Guo, a professor in the Department of Electrical Engineering and Computer Science and principal investigator.

“It’s not cloaking, as the object can still cast a shadow. But if you put an object on a black background, then with this coating, it could really become invisible.”

A paper on the research is newly published online in Applied Physics Letters.

To demonstrate this concept, the researchers made a raised, microscopic tank shape on a piece of silicon. They then grew the carbon nanotube carpet on top of the entire silicon chip. In photos taken through an optical microscope, they show that the tank is imperceptible. As a control, they did this again, carving out a rectangle that was not coated with carbon nanotubes. The rectangle is visible on this chip, but the tank remains hidden.

Here’s how the new coating works: Human eyes perceive an object based on how it reflects or scatters light. The “refractive index” of this new coating is similar to that of air, meaning light traveling through air doesn’t scatter or reflect when it hits the coating.

It’s well known that carbon nanotubes are capable of absorbing light, but the researchers were able to push it to such a high percentage by spacing them just right.

The “perfect black” material Guo’s team created for this coating has a host of varied applications. It could possibly be used in display screens for ultra-high contrast and a crisper picture. It holds promise as solar heating device. The National Institute of Standards and Technology is using a similar material to absorb infrared light and measure the amount of heat it can generate.

The coating could inspire a new type of camouflaging paint for stealth aircraft. Today’s stealth planes use shape to scatter electromagnetic waves and avoid detection, and this scheme could actually absorb the waves.

“The carbon nanotube forest can absorb very wide range of electromagnetic wave from ultraviolet up to terahertz,” Guo said, “and in principle it can be applied to an arbitrary sized object.”

Just how large an object? Guo suggested an intriguing possibility—perhaps entire planets or even stars.

“Since deep space itself is a perfect dark background, if a planet or star were surrounded by a thick, sooty atmosphere of light-absorbing carbon nanomaterial gases, it would become invisible due to the same principle,” Guo said. “It would become totally dark to our instruments that rely on the detection of electromagnetic waves. Could this explain some of the missing matter in the universe?”

X-rays or gamma rays would be able to penetrate through the hypothetical “dark veil” Guo proposes. Or, objects behind such veils would cast a shadow by distant stars behind them.


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Blandford, R. D. Sources of Gravitational Radiation (ed. Smarr, L.) (Cambridge University Press, 1979).

Ostriker, J. P. & Tremaine, S. D. Astrophys. J. Lett. 202, 113 (1975).

Ostriker, J. P. & Hausman, M. A. Astrophys. J. Lett. 217, 125 (1977).

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Lynden-Bell, D. in Relativity Theory and Astrophysics Vol. 2 (ed. Ehlers, J.) 131 (American Mathematical Soc., 1967).

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Begelman, M. C. et al. Astrophys. J. 238, 722 (1980).

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Saslaw, W. C., Valtonen, M. J. & Aarseth, S. J. Astrophys. J. 190, 253 (1974).


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AST-A 100 - The Solar System

Credits: 3 Description: Fall. Survey of the solar system, including the Earth, sun, moon, eclipses, planets and their satellites, comets, laws of planetary motion, etc. Discussion of the origin of the solar system, life on earth, and the possibilities of extraterrestrial life. Also astronomical instruments and celestial coordinates.

AST-A 103 - Search for Life in the Universe

Credits: 3 Description: Spring. Explores the origin, nature, and history of life on Earth, prospects for life in our own and other planetary systems, extra solar planet detection, and the possibility of other technological civilizations.

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Credits: 3 Description: Fall, Spring. For students not ready to take the algebra- and trigonometry-based courses in physics (PHYS 21800 and PHYS-P 201). Basic concepts of physics. Methods of analyzing physics problems. Setting up equations for physics problems. Interpreting information in physics problems. Analyzing and presenting the results of laboratory measurements. Extensive drill in these topics. Prerequisite: MATH 15900, or MATH 15300 and MATH 15400, or equivalent.

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Credits: 4 Description: Fall, day Spring, day, night Summer, day. Statics, uniform and accelerated motion Newton's laws circular motion energy, momentum, and conservation principles dynamics of rotation gravitation and planetary motion properties of matter and simple harmonic and wave motion. Prerequisite: or C: MATH 16600. Equiv. IU PHYS-P 221.

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PHYS-P 202 - General Physics II

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PHYS 21800 - General Physics

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PHYS 25100 - Heat, Electricity, and Optics

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PHYS 28500 - Introduction to Biophysics

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PHYS 29000 - Special Assignments

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AST-A 100 - The Solar System

Course Summary: Fall. Survey of the solar system, including the Earth, sun, moon, eclipses, planets and their satellites, comets, laws of planetary motion, etc. Discussion of the origin of the solar system, life on earth, and the possibilities of extraterrestrial life. Also astronomical instruments and celestial coordinates.

AST-A 103 - Search for Life in the Universe

Course Summary: Spring. Explores the origin, nature, and history of life on Earth, prospects for life in our own and other planetary systems, extra solar planet detection, and the possibility of other technological civilizations.

AST-A 105 - Stars and Galaxies

Course Summary: Spring. Survey of the universe beyond the solar system, including stars, pulsars, black holes, principles of spectroscopy and the H-R diagram, nebulae, the Milky Way, other galaxies, quasars, expanding universe, cosmology, and extraterrestrial life.

AST-A 130 - Short Courses in Astronomy

Course Summary: Five-week short courses on a variety of topics in astronomy. Examples of topics include: the Big Bang, Black Holes, Astronomy from your Backyard, How to See Stars, and The Birth and Death of Our Sun.

AST-A 205 - Quasars, Pulsars, Black Holes

Course Summary: Fall, day. For both science and non-science majors interested in astronomy. Surveys stars of all types and their life cycles. Includes the H-R diagram, star clusters, and exploration of our own sun. Discussion of relativistic effects on certain astronomical objects and on human space exploration.

PHYS 01000 - Pre-Physics

Course Summary: Fall, Spring. For students not ready to take the algebra- and trigonometry-based courses in physics (PHYS 21800 and PHYS-P 201). Basic concepts of physics. Methods of analyzing physics problems. Setting up equations for physics problems. Interpreting information in physics problems. Analyzing and presenting the results of laboratory measurements. Extensive drill in these topics.

PHYS 10000 - Physics in the Modern World

Course Summary: Spring, day. Ideas, language, methods, and impact of physics today.

PHYS 12100 - How to Solve a Problem without Solving the problem

Course Summary: Fall. This course teaches students how to formulate a research question and start doing research with their current knowledge. Enrollment with permission of the instructor.

PHYS 12200 - How To Know When You Are Right

Course Summary: Spring. This course continues developing students' capabilities to perform research. Prerequisite PHYS 12100. Enrollment with the permission of the instructor.

PHYS 14000 - Short Courses in Physics

Course Summary: Five-week courses on a variety of topics related to the physical world. Examples of topics include: Waves and Particles Are the Same Thing, Relativity, Quarks and Other Inhabitants of the Zoo, Why Things Work and Why They Don't, Lasers and Holography, and Physics of Star Trek.

PHYS 15200 - Mechanics

Course Summary: Fall, day Spring, day, night Summer, day. Statics, uniform and accelerated motion Newton's laws circular motion energy, momentum, and conservation principles dynamics of rotation gravitation and planetary motion properties of matter and simple harmonic and wave motion.

PHYS 15250 - Honors Mechanics Seminar

Course Summary: The primary goal of the course is to enrich the student's experience in PHYS 15200 by presenting a topic not traditionally covered in first-year physics, such as special relativity, quantum mechanics, or particle physics. The course will meet weekly for 50 minutes, during which time there will be a lecture and/or a class discussion. The course will carry honor's credit.

PHYS 20000 - Our Physical Environment

Course Summary: Fall, night Spring, night. A nonmathematical introduction to physical concepts and methods by means of examples from daily life and current technological applications.

PHYS-P 201 - General Physics I

Course Summary: Fall, day Spring, night Summer, day. Newtonian mechanics, wave motion, heat, and thermodynamics. Application of physical principles to related scientific disciplines, especially life sciences. Intended for students preparing for careers in the life sciences and the health professions. Three lectures, one discussion section, and one two-hour laboratory period each week.

PHYS-P 202 - General Physics II

Course Summary: Fall, night Spring, day Summer, day. Electricity and magnetism geometrical and physical optics introduction to concepts of relativity, quantum theory, and atomic and nuclear physics. Three lectures, one discussion section, and one two-hour laboratory period each week.

PHYS 21800 - General Physics

Course Summary: Fall, night Spring, night Summer, day. Mechanics, conservation laws, gravitation simple harmonic motion and waves kinetic theory, heat, and thermodynamics for students in technology fields.

PHYS 21900 - General Physics

Course Summary: Fall, night Spring, night Summer, day. Electricity, light, and modern physics.

PHYS 25100 - Heat, Electricity, and Optics

Course Summary: Fall, day, night spring, day summer, day. Heat, kinetic theory, elementary thermodynamics, and heat transfer. Electrostatics, electrical currents and devices. Magnetism, electromagnetic radiation, optics.

PHYS 28500 - Introduction to Biophysics

PHYS 29000 - Special Assignments

Course Summary: Readings, discussions, written reports, or laboratory work selected for enrichment in special areas of physics.


Galaxy May Be Missing Its Supermassive Black Hole, Says NASA

Astronomers are still puzzling over why they aren’t detecting a supermassive black hole (SMBH) in the center of the bright cluster galaxy Abell 2261 (A2261-BCG). Despite recent observations with NASA’s Chandra X-ray Telescope and NASA’s Hubble Space Telescope, there’s little evidence for an expected colossal black hole in a galaxy in the cluster’s core.

The observations, detailed in a paper appearing in a journal of the American Astronomical Society (AAS), posit that this galaxy underwent a merger with another galaxy in the past, which could have caused a newly formed larger black hole to be ejected. Or says NASA, their observations were simply not sensitive enough to pick up the signatures of such a colossal black hole.

Lying more than 2 billion light-years away in the constellation of Hercules, the astronomers used Chandra to look for material that has been superheated as it fell towards the black hole and produced x-rays, but did not detect such a source. The authors concluded that either there is no black hole at any of these locations, or that it is pulling material in too slowly to produce a detectable x-ray signal.

Yet it’s fairly certain this galaxy has or had a giant black hole in it at some point, Sarah Burke-Spolaor, an astrophysicist at West Virginia University and the paper’s lead co-author, told me. But it's so far eluded deep searches using some of the world’s most sensitive optical, x-ray and radio telescopes, she says.

But the team has used one of the best x-ray telescopes ever constructed to observe this cluster for a total of 36 hours and they still don’t detect this missing black hole.

Astronomers used searched the center of the image for evidence of a black hole, weighing between 3 . [+] and 100 billion times the Sun.

NASA/CXC/Univ of Michigan/K. Gültekin Optical: NASA/STScI and NAOJ/Subaru Infrared: NSF/NOAO/KPNO Radio: NSF/NOAO/VLA)

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Could it have been kicked out of this galaxy altogether?

This SMBH may have actually been kicked out of this galaxy’s center via a process known as gravitational wave recoil, Kayhan Gultekin, an astronomer at the University of Michigan and the paper’s lead author, told me. It’s a process that requires two such massive black holes to essentially merge. This process would begin with two black holes orbiting each other. And as they orbit each other, each black hole would emit ripples in spacetime known as gravitational waves.

As they get closer to each other, they emit gravitational waves more strongly, says Gultekin. If the gravitational waves are emitted asymmetrically in any way, the momentum goes in a certain direction, he says. If the gravitational waves are carrying a lot of momentum in one direction, something has to go in the other direction, notes Gultekin. In this case, he says, that’s the black hole binary and/or the post-merger single black hole.

But to make sense of this process, Gultekin says it requires some pretty heavy mathematical lifting.

It's a complicated mess that requires complicated numerical relativity calculations to determine how fast the recoil is, says Gultekin. But the best estimates put the maximum at above 5,000 km/s (11,000,000 mph or 1.7 percent of the speed of light), he says.

“That’s enough to kick the black hole entirely out of the galaxy and be long gone,” said Gultekin. “It would be cruising in intergalactic space.”

If recoils can be large, it also leads to the possibility of supermassive black holes that might be wandering, unseen, in the Universe, says Burke-Spolaor. Recoils have never been conclusively demonstrated, only theorized, so this object is of high interest as a leading candidate for black hole recoil, she says.

Yet Gultekin says it’s too soon to conclude there isn’t a supermassive black hole in A2261-BCG. But if it’s not there, it would be the only such large galaxy yet discovered without such a massive black hole at its center. Even our own Milky Way’s supermassive black hole is relatively quiescent but it’s there.

NASA’s upcoming James Webb Space Telescope (JWST) should be able to garner more details about the cluster and potentially solve this mystery, however.

Based on theoretical calculations, the only reasonable explanation for a bright cluster galaxy to be missing its supermassive black hole is because it has been ejected from the galaxy, says Gultekin.

“[But] it's really, really hard to move something that's more than a billion times the mass of the Sun,” said Burke-Spolaor.


A black &ldquosuperhole&rdquo possibility? - Astronomy

Supermassive black holes with the mass of many millions of stars are thought to lie at the center of most large galaxies. The evidence comes from optical and radio observations which show a sharp rise in the velocities of stars or gas clouds orbiting the centers of galaxies. High orbital velocities mean that something massive is creating a powerful gravitational field which is accelerating the stars. X-ray observations indicate that a large amount of energy is produced in the centers of many galaxies, presumably by the in-fall of matter into a black hole.

How could a supermassive black hole form in the center of a galaxy? One idea is that an individual starlike black hole forms and swallows up enormous amounts of matter over the course of millions of years to produce a supermassive black hole. Another possibility is that a cluster of starlike black holes forms and eventually merges into a single, supermassive black hole. Or, a single large gas cloud could collapse to form a supermassive black hole.

Recent research, including results from Chandra (see 3C294, Perseus Cluster, NGC 4636, Centaurus A) suggests that galaxies and their black holes do not grow steadily, but in fits and starts. In the beginning of a growth cycle, the galaxy and its central black hole are accumulating matter. The energy generated by the jets that accompany the growth of the supermassive black hole eventually brings the infall of matter and the growth of the galaxy to a halt. The activity around the central black hole then ceases because of the lack of a steady supply of matter, and the jets disappear. Millions of years later the hot gas around the galaxy cools and resumes falling into the galaxy, initiating a new season of growth.


Astronomers Detect A Black Hole On The Move

Scientists have long theorized that supermassive black holes can wander through space--but catching them in the act has proven difficult.

Now, researchers at the Center for Astrophysics | Harvard & Smithsonian have identified the clearest case to date of a supermassive black hole in motion. Their results are published today in the Astrophysical Journal.

"We don't expect the majority of supermassive black holes to be moving they're usually content to just sit around," says Dominic Pesce, an astronomer at the Center for Astrophysics who led the study. "They're just so heavy that it's tough to get them going. Consider how much more difficult it is to kick a bowling ball into motion than it is to kick a soccer ball -- realizing that in this case, the 'bowling ball' is several million times the mass of our Sun. That's going to require a pretty mighty kick."

Pesce and his collaborators have been working to observe this rare occurrence for the last five years by comparing the velocities of supermassive black holes and galaxies.

"We asked: Are the velocities of the black holes the same as the velocities of the galaxies they reside in?" he explains. "We expect them to have the same velocity. If they don't, that implies the black hole has been disturbed."

For their search, the team initially surveyed 10 distant galaxies and the supermassive black holes at their cores. They specifically studied black holes that contained water within their accretion disks -- the spiral structures that spin inward towards the black hole.

As the water orbits around the black hole, it produces a laser-like beam of radio light known as a maser. When studied with a combined network of radio antennas using a technique known as very long baseline interferometry (VLBI), masers can help measure a black hole's velocity very precisely, Pesce says.

The technique helped the team determine that nine of the 10 supermassive black holes were at rest--but one stood out and seemed to be in motion.

Located 230 million light-years away from Earth, the black hole sits at the center of a galaxy named J0437+2456. Its mass is about three million times that of our Sun.

Using follow-up observations with the Arecibo and Gemini Observatories, the team has now confirmed their initial findings. The supermassive black hole is moving with a speed of about 110,000 miles per hour inside the galaxy J0437+2456.

But what's causing the motion is not known. The team suspects there are two possibilities.

"We may be observing the aftermath of two supermassive black holes merging," says Jim Condon, a radio astronomer at the National Radio Astronomy Observatory who was involved in the study. "The result of such a merger can cause the newborn black hole to recoil, and we may be watching it in the act of recoiling or as it settles down again."

But there's another, perhaps even more exciting possibility: the black hole may be part of a binary system.

"Despite every expectation that they really ought to be out there in some abundance, scientists have had a hard time identifying clear examples of binary supermassive black holes," Pesce says. "What we could be seeing in the galaxy J0437+2456 is one of the black holes in such a pair, with the other remaining hidden to our radio observations because of its lack of maser emission."

Further observations, however, will ultimately be needed to pin down the true cause of this supermassive black hole's unusual motion.

Co-authors of the new study are Anil Seth of the University of Utah Jenny Greene of Princeton University Jim Braatz, Jim Condon, and Brian Kent of the National Radio Astronomy Observatory and Davor Krajnovi? of the Leibniz Institute for Astrophysics in Potsdam, Germany.