Supermassive black holes may frequently roam galaxy centers

May 25, 2010
Hubble Space Telescope Images of M87. At right, a large scale image taken with the Wide-Field/Planetary Camera-2 from 1998 (NASA and the Hubble Heritage Team (STScI/AURA), J. A. Biretta, W. B. Sparks, F. D. Macchetto, E. S. Perlman). The two images at left show an image taken in 2006 with the Advanced Camera for Surveys' High Resolution Channel. The position of the supermassive black hole is indicated by the black dot in the lower left panel, and a knot in the jet (HST-1), which was flaring in 2006, is also indicated on this panel. The red dot indicates the center of the galaxy's light distribution, which is offset from the position of the black hole by 22 +/- 3 light years. Credit: (NASA and the Hubble Heritage Team (STScI/AURA), J. A. Biretta, W. B. Sparks, F. D. Macchetto, E. S. Perlman).

A team of astronomy researchers at Florida Institute of Technology and Rochester Institute of Technology in the United States and University of Sussex in the United Kingdom, find that the supermassive black hole (SMBH) at the center of the most massive local galaxy (M87) is not where it was expected. Their research, conducted using the Hubble Space Telescope (HST), concludes that the SMBH in M87 is displaced from the galaxy center.

The most likely cause for this SMBH to be off center is a previous merger between two older, less massive, SMBHs. "We also find, however, that the iconic M87 jet may have pushed the SMBH away from the galaxy center," said Daniel Batcheldor, Florida Tech assistant professor in the Department of Physics and Space Sciences, who led the investigation.

The study of M87 is part of a wider HST project directed by Andrew Robinson, professor of physics at RIT. "What may well be the most interesting thing about this work is the possibility that what we found is a signpost of a black hole merger, which is of interest to people looking for and for people modeling these systems as a demonstration that really do merge," says Robinson. "The theoretical prediction is that when two black holes merge, the newly combined black hole receives a 'kick' due to the emission of gravitational waves, which can displace it from the center of the galaxy."

David Merritt, professor of physics at RIT, adds: "Once kicked, a can take millions or billions of years to return to rest, especially at the center
of a large, diffuse galaxy like M87. So searching for displacements is an effective way to constrain the merger history of ."

Jets, such as the one in M87, are commonly found in a class of objects called . It is commonly believed that supermassive black holes can
become active as a result of the merger between two galaxies, the infall of material into the center of the galaxy, and the subsequent merger between their black holes.

Therefore, it is very possible that this finding could also be linked to how active galaxies—including quasars, the most luminous objects in the universe—are born and how their jets are formed.

This research will be presented at the American Astronomical Society (AAS) Conference on May 25 in Miami, Fla. It will also be published in The Astrophysical Journal Letters peer-reviewed scientific journal.

Because many galaxies have similar properties to M87, it is likely that SMBHs are commonly offset from their host galaxy centers. The potential offsets, however, would be very subtle and researchers would rely on the to detect them.

"Unfortunately, the highest spatial resolution camera onboard HST could not be revived during the recent servicing mission. This means we have to rely on the huge archive of HST data to find more of these vagrant SMBHs, as we did for M87," added Batcheldor.

Regardless of the displacement mechanism, the implication of this result is a necessary shift in the classic SMBH paradigm; no longer can it be assumed that all SMBHs reside at the centers of their host galaxies. This may result in some interesting impacts on a number of fundamental astronomical areas, and some
interesting questions.

For example, how would an accreting (growing by the gravitational attraction of matter) or quiescent SMBH interact with the surrounding nuclear environment as it moves through the bulge? What are the effects on the standard orientation-based unified model of active galactic nuclei and how have dynamical models of the SMBH mass been centered if the SMBH is quiescent?

Especially thought-provoking, added Eric Perlman, associate professor of physics and space sciences at Florida Tech, is that our own galaxy is expected to merge with the Andromeda galaxy in about three billion years. "The result of that merger will likely be an active elliptical galaxy, similar to M87. Both our galaxy and Andromeda have SMBHs in their centers, so our result suggests that after the merger, the SMBH may wander in the galaxy's nucleus for billions of years."

David Axon, Dean of Mathematical and Physical Sciences at Sussex, concludes by saying that "In current galaxy formation scenarios galaxies are thought to be
assembled by a process of merging. We should therefore expect that binary black holes and post coalescence recoiling black holes, like that in M87, are very common in the cosmos."

Explore further: Staying warm: The hot gas in clusters of galaxies

More information: "A Displaced Supermassive Black Hole in M87." The paper is available here: arXiv.org/abs/1005.2173

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in7x
not rated yet May 25, 2010
Why is no event horizon observable?
omatumr
1 / 5 (6) May 25, 2010
Supermassive "black holes" are supermassive neutron stars energized by neutron repulsion (NR).

NR causes neutron emission from the cores of ordinary stars. They then decay to form the Hydrogen that pours from stars to fill interstellar space.

NR causes fragmentation of massive neutron stars to produce galaxies of stars.

Galaxy formation by fragmentation was suggested by Wilbur K. Brown [Astrophysics and Space Science, 15, 293-306 (1972)].

This concept was developed further in several other papers:

W. K. Brown, Astrophys. & Space Sci., 72, 15-31 (1980); Astrophys. & Space Sci., 121, 351-355 (1986); Astrophys. & Space Sci., 122, 287-298 (1986).

W. K. Brown and L. A. Gritzo, Astrophys. & Space Sci., 123, 161-181 (1986); Astrophys. & Space Sci., 126, 255-267 (1986).

G. A. Harutyunian, Astrophys., 46, 81-91 (2003); Astrofizika, 46, no. 1, 103-118 (2003).

O. Manuel, M. Mozina & H. Ratcliffe, Journal of Fusion Energy, 25, 107-114 (2006)

Oliver K. Manuel
in7x
not rated yet May 25, 2010
So are you suggesting that "event horizons" don't exist since all "black holes" are neutron stars? Or is this simply an isolated example?
yyz
5 / 5 (3) May 25, 2010
in7x:

The event horizon for the 6 billion solar mass SMBH at the center of M 87 is way too small to be resolved by optical means (or any other, at this time)at the distance of the Virgo Cluster, for one. At the same time, a 6 billion solar mass neutron star is highly unlikely to exist in nature. Precisely how does a 6 billion Msun neutron star "fragment" into a multitrillion Msun giant elliptical galaxy. Does a paper exist specifically concerning M 87 and a supermassive neutron star in its nucleus fragmenting and generating a galactic jet to boot? Check out: http://en.wikiped...mponents

omatumr
1 / 5 (3) May 25, 2010
So are you suggesting that "event horizons" don't exist since all "black holes" are neutron stars?


Yes.

The results of space-age measurements on material in meteorites, planets, the photosphere, the Moon, the solar wind and solar flares indicate that:

1. Our Sun formed on the collapsed core of the supernova that gave birth to the solar system, and

2. NR in the solar core causes neutron-emission and triggers a series of reactions that produce solar luminosity, solar neutrinos and solar-wind H (the product of neutron-decay) in the proportions observed.

NR caused massive neutron stars to fragment and produce galaxies of ordinary stars.

With kind regards,
Oliver K. Manuel
yyz
5 / 5 (1) May 25, 2010
"NR caused massive neutron stars to fragment and produce galaxies of ordinary stars."

How do galaxies _without_ supermassive "neutron stars" form? Many galaxies, like M 33, show no sign of a SMBH at their nucleus. What "fragmented' to form M 33? Or dwarf galaxies with no nucleus at all?

And what about M 87 in particular? Again, I ask "Does a paper exist specifically concerning M 87 and a supermassive neutron star in its nucleus fragmenting and generating a galactic jet to boot?"
vidar_lund
5 / 5 (4) May 26, 2010
Oliver, you keep on defending your NR theories and I respect that but it doesn't make any sense. The sun doesn't contain a neutron star, that would be a very unstable system. A neutron star would rip the sun apart, it's an extremely dense object. Can you please explain to me why the sun is not imploding onto the neutron star and turning into a tiny ball 10 kilometers wide?
gwrede
4 / 5 (2) May 26, 2010
"We also find, however, that the iconic M87 jet may have pushed the SMBH away from the galaxy center,"


I don't think so. With the mass of a SMBH, the required jet would have to have a preposterous luminosity to make any detectable impulse on the SMBH.

And if that's not enough, there are two jets in opposite directions. So, we'd have to have a mechanism that suppresses one of the jets, and not the other, or else we'd have no net impulse.

This mechanism should also remain stable for a very long time. But the galaxy core and the accretion disk are violent and aggressive systems, which makes that unlikely.

---

The notion, however, that the SMBH isn't necessarily stationary at the exact center of the galaxy, is refreshing. In hindsight, it's not even obvious, it's self-evident. I for example, feel ashamed that it never crossed my mind to question it.

Like someone said, what matters, are the right questions!
omatumr
1 / 5 (3) May 26, 2010
Oliver, you keep on defending your NR theories and I respect that but . . . .

A neutron star would rip the sun apart, it's an extremely dense object.


Thanks, vidar, for your comment.

The high density of the energetic, highly magnetic neutron star at the core of the Sun does not "rip it apart", but it does produce the well-known cycle of magnetic storms and sun-spots at the solar surface as the ever-changing positions of massive planets jerk the Sun, "like a yo-yo on a string," about the center-of-mass of the solar system ["Earth's heat source - The Sun", Energy & Environment 20 (2009) 131-144]

With kind regards,
Oliver

yyz
not rated yet May 26, 2010
gwerde, displacement of the SMBH by a jet mechanism was only one of four possible options the authors explored. Jet displacement and displacement due to a past major merger were deemed the two most likely scenarios.From the abstract:

"...the displacement could be due to residual oscillations resulting from a large recoil that occurred in the aftermath of a major merger any time in the last 10 Gyr."

Given that M 87 is a massive cD type galaxy sitting in the gravity well of the Virgo Cluster, it has probably undergone several major and many minor mergers over the past 10 Gyr. This would account for its extreme mass and an unusually large population of globular clusters. A careful assessment of the jet displacement scenario is also made, noting several of the factors you have mentioned (i.e. jet stability and presence of a low density nuclear region).Many galaxies may have displaced SMBHs at some time in their life. M 87 is just one of many (and close enough to check).
barakn
3 / 5 (2) May 26, 2010
I don't think so. With the mass of a SMBH, the required jet would have to have a preposterous luminosity to make any detectable impulse on the SMBH.

And if that's not enough, there are two jets in opposite directions.

The jet consists of relativistic particles, so each particle could have a staggering amount of momentum. Have you performed a calculation that suggests the jet would be incapable of imparting much momentum to the black hole or are you just relying on your intuition?
Where's the second jet? I don't see it.
in7x
5 / 5 (1) May 26, 2010
"Where's the second jet? I don't see it."

Had you quote his next sentence: "So, we'd have to have a mechanism that suppresses one of the jets [...]"

But I'm being facetious. I take it that gwrede is not necessarily suggesting that there are two jets produced by M87, only that in a more general sense that two jets are usually produced by most SMBHs. NGC4261 for example: http://csep10.phy...arge.jpg

I enjoy this statement: "The black hole itself presumably lies inside the bright spot at the center."

But yyz's proclamation is echoed: "Even a billion solar mass black hole would be too small to see in this image, for as we see in the following table, it would only be the size of the solar system."
in7x
5 / 5 (1) May 26, 2010
Just as an aside regarding jet formation: "Material in the center of the galaxy, such as nearby stars and gas, gets pulled in by the black hole's overwhelming gravity and forms a disk orbiting around the core (the material's inertia keeps it spiraling in a disk rather than falling straight into the black hole). The distorted magnetic field lines seem to pull charged particles off the disk and cause them to gush outward at nearly the speed of light."

Sounds like a magneto-hydrodynamic engine.

Back to M87: "jet of high-speed electrons approximately 6500 light years long"

I suppose we only need to estimate (or find) the density of the jet to solve your equation.
71STARS
1 / 5 (3) May 29, 2010
My Firm Belief: There are NO "Black Holes." When a Sun shrinks/shrivels/dies, it most naturally becomes a "frozen star" (Russian terminology 1930s). No power, no LIGHT emission; simply a core of matter which will dissolve/dissipate over Time in Empty Space. To state Black Holes EXIST in the center of ALL galaxies now is pure nonsense. Immense luminosity at the center says SUNS, LIGHT, activity for generation of more SUNS, which equates to the "power" scientists have erroneously depicted as a black hole's gravitational pull! Q. Is a galaxy center "dark" or "immensely ablaze"? Common sense answer is obvious.
yyz
5 / 5 (1) May 29, 2010
"To state Black Holes EXIST in the center of ALL galaxies now is pure nonsense."

Who, precisely, is stating this?
JoeDuff
not rated yet May 29, 2010
Rather then WHO I'd ask him WHY. If you would have a good reason, you will not required to believe in some authority.
Husky
1 / 5 (1) May 30, 2010
Black "Hole" might be the most unfortunate analogy to describe the hole in our knowledge about the true nature of these objects and may have held generations back in attempting to develop new theories to fill that hole, such as quarkstars, preonstars and magnatars
Husky
not rated yet May 30, 2010
I don't have any figures but I would guess that these enormous relativistic jets put out enough thrust to move the mass of a jupiter sized planet and perhaps the massive black hole itself considerably, if this is not canceled out by:
- a jet on the opposing side (are there monojet blackholes?, or are there opposing jet black holes where one jet is weaker?)
JoeDuff
1 / 5 (2) May 30, 2010
Yes, they're many asymmetric black holes. I presume, it's the manifestation of CP-symmetry breaking.
71STARS
1 / 5 (2) Jun 01, 2010
Who is stating Black Holes exist in the center of ALL galaxies now is pure nonsense? A. Anyone with basic knowledge of origination of Black Holes Theory. Orig. Concept: Suns die, shrink, gain immense gravitational POWER, but no illumination; therefore a dark, dead, POWERFUL entity. Then the erroneous embellishment of named black holes took on a life of its own, up to the present announcement that all galaxies contain a Black Hole in its center!! Think: WHY would one dying star "gain" POWER? What other entity in universe dies and "gains" power? There are no black holes as envisioned today. Black Stars exist: dead, no power, frozen dynamics, hinder no one. Time to abandon a wrongful out-of-control theory; there is no shame to be overriden by pure logic. Re-thinking is required.

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