Magnetic fields in powerful radio jets

December 28, 2015
X-ray jets from the galaxy Pictoris A. The greyscale image was taken by the Chandra X-ray Observatory and reveals the detailed X-ray structure of the jets, which extend over nearly one million light-years. The red contours show the radio emission. Astronomers analyzing these and other data have concluded that the X-ray emission is produced by rapidly moving charged particles in magnetic fields. Credit: NASA/Chandra, Hardcastle et al.

Super-massive black holes at the centers of galaxies can spawn tremendous bipolar jets when matter in the vicinity forms a hot, accreting disk around the black hole. The rapidly moving charged particles in the jets radiate when they are deflected by magnetic fields; these jets were discovered at radio wavelengths several decades ago. In the most dramatic cases, the energetic particles move at speeds close to the speed of light and extend over hundreds of thousands of light-years, well beyond the visible boundaries of the galaxy. The physical processes that drive these jets and cause them to radiate are among the most important outstanding problems of modern astrophysics.

One of the most significant and unexpected discoveries of the Chandra X-ray Observatory was that bright X-rays are also emitted by these . The X-rays are also produced by the acceleration of charged particles, at least according to some models, but there are other possible mechanisms as well. Fast-moving particles can scatter background light, boosting it into the X-ray band. Alternatively, shocks can generate X-ray emission (or at least a significant portion of it), either as the jets interact with stellar winds and interstellar medium or, within the jet, as a consequence of jet variability, instability, turbulence, or other phenomena.

CfA astronomer Aneta Siemiginowska and her colleagues have studied the bright radio jet galaxy Pictoris A, located almost five hundred million light-years away, using very deep Chandra measurements - the observations used an accumulated total of over four days of time, spread over a fourteen year period. These data enabled the first detailed analysis of the spectral character of the emission all along the jets. The emission turns out to be remarkably uniform everywhere, something that is extremely unlikely if scattering were responsible, but which is a natural consequence of the magnetic field process. The scientists therefore reject the scattering model in favor of the latter. However, the jets do have within them many small clumps, internal structures, and lobes. Shocks and/or scattering are possible explanations for the emission in some of these structures.

Although these new results represent some dramatic improvements in our understanding of Pic A, high-resolution radio measurements of a large sample of similar jets are now needed to refine and extend the models. Large-scale X-ray jets, for example, have been also detected in very distant quasars. The results from Pic A, together with future Chandra observations, will help astronomers determine the extent to which these distant jets also rely on the same processes, or if they invoke other ones.

Explore further: Powerful jets from non-spinning black holes

More information: M. J. Hardcastle et al. Deep observations of Pictor A , Monthly Notices of the Royal Astronomical Society (2015). DOI: 10.1093/mnras/stv2553

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HannesAlfven
3 / 5 (16) Dec 28, 2015
Re: "The emission turns out to be remarkably uniform everywhere, something that is extremely unlikely if scattering were responsible, but which is a natural consequence of the magnetic field process."

This article is rather symbolic of what is happening in the space sciences today ...

(1) We are prone to inferring processes in space that are like the ones we are surrounded by here on Earth.

(2) The article runs through all of the various tools that the astrophysicists have at their disposal to explain the observation, using this approach.

(3) At the end of all of that, it is revealed that this was actually a pointless exercise, because the jet is instead likely an electrodynamic phenomenon -- one of the few laboratory-observed processes that astrophysicists tend NOT to infer for large-scale astrophysical phenomena.

(4) For next article, go back to step 1.
Hyperfuzzy
3.3 / 5 (10) Dec 28, 2015
Electrodynamic? Looks like a dipole and given the jets, a magnetic dipole created by circular motion. Else it's magic!
Jeffhans1
3.2 / 5 (5) Dec 28, 2015
It is almost as if the jets are relieving the pressure that is caused by the energy release when matter is compressed into whatever form that it takes within black holes. If the entire thing is spinning fast enough to cause the magnetic field around it become compressed and warped to avoid moving faster than light, it could release the dual jet beam at the poles as energy to balance the equation for the magnetic particles that can't move any faster without violating the laws of physics.
vidyunmaya
1.7 / 5 (12) Dec 29, 2015
Sub: science advancement
excellent image that provides Paradigm shift from Black-hole psychology [Super-imposed Ignorance]
either side magnetic fields -with a Central Heart region.Space data help unravel mysterious Energies -Radio-jets- to wake-up to Knowledge base -Pictoris A, located almost five hundred million light-years . this is a region for dynamic Region that supports -Wave Energy Dynamics- Cosmic Dance of SIVA- My search beyond Heart of the universe. Cosmology vedas interlinks- prime concepts to Base concepts at Milky-way galaxy under Control and regulation.see Books available at LULU.http://www.lulu.c...039.html
Steelwolf
3.8 / 5 (10) Dec 30, 2015
And is it not funny that someone who Thought They KNEW It All told me there WERE no such large magnetic structures on Galactic scales.

I find it particularly funny that on the articles that distinctly prove things not to his liking that Capt Stump is not here saying this is not what it seems to be based on what the scientists themselves said.

Sorry, but the Electric Universe Theory (which does not exclude gravitational effects, only adds to them) keeps coming out with more and more backing information and data from a very wide variety of sources such that those who are naysayers to the entire Electric Universe theory are finding themselves painted into a tiny, tight corner where there is no way out but to say they WERE WRONG, that the Magneto Electric effect has far greater reaching effect than just gravity alone.

Time to update outworn ideas! That IS what True Science is all about, not defending your own pet theory to death.
HannesAlfven
3.5 / 5 (11) Dec 30, 2015
Re: "Time to update outworn ideas! That IS what True Science is all about, not defending your own pet theory to death."

We need to fund Dr. Pollack's Institute for Venture Science. Otherwise, electrical cosmology will be stuck in this phase of being locked out of funding long past our lifetimes. When you have painted yourself into a corner where your career utterly depends upon the validity of your idea, then you will defend it through whatever means is available to you, and regardless of the presence of better ideas. We have to create a path for new ideas in the sciences to elaborate such that they can unseat textbook theories. The IVS can do this.
my2cts
2.8 / 5 (13) Dec 30, 2015
@ Steelwolf
"no such large magnetic structures"
There _are_ galactic scale magnetic fields of very weak strength, 1-10 microgauss,
but these values are totally insufficient to influence galactic dynamics.
cantdrive85
3 / 5 (10) Dec 30, 2015
@ Steelwolf
"no such large magnetic structures"
There _are_ galactic scale magnetic fields of very weak strength, 1-10 microgauss,
but these values are totally insufficient to influence galactic dynamics.

The electric field is where most of the work is getting done.
Protoplasmix
5 / 5 (6) Dec 31, 2015
The electric field is where most of the work is getting done.
And for all possible inertial frames, in how many do you observe just an electric field?
my2cts
2.6 / 5 (10) Dec 31, 2015
@cd45
For the Sun to experience a force equal to galactic gravity, the product of solar and galactic charge, assumed spherically distributed, must be 3*10^51. That is absolutely huge and should lead to observable effects.
What is the upper limit on the sun's charge and galactic electric fields from the stark effect?
you should have those numbers readily available.
HannesAlfven
3.9 / 5 (7) Jan 02, 2016
Re: "And for all possible inertial frames, in how many do you observe just an electric field?"

What we observe is that the solar wind fails to appreciably decelerate even as it passes the Earth's orbit. Solar physicists have proposed a variety of exotic mechanisms to explain it, yet try too hard to ignore the most sensible, from the laboratory, because such an admission would place far too much importance on the role of plasma in large-scale dynamics.

It's a peculiar situation -- and perhaps one of the few across all scientific domains -- where the laboratory observation is considered a completely preposterous and out-of-bounds inference.

The history for why it turned out this way can be traced back to the widespread belief that space is an empty vacuum.

See snapshots here ...

https://plus.goog...N6Miph3x
my2cts
2.3 / 5 (9) Jan 02, 2016
@HA
"fails to appreciably decelerate"
Newton's first law.
Mike_Massen
2 / 5 (12) Jan 03, 2016
HannesAlfven says
What we observe is that the solar wind fails to appreciably decelerate even as it passes the Earth's orbit
What do you imagine is special re Earth's orbit ?

HannesAlfven claims
Solar physicists have proposed a variety of exotic mechanisms to explain it, yet try too hard to ignore the most sensible, from the laboratory, because such an admission would place far too much importance on the role of plasma in large-scale dynamics
Q's

1. Do you consider escape velocity an "exotic mechanism" ?

2. Why *should* solar wind decelerate & by how much, heard of escape velocity re the calculus of limits, ie gravitational attractive force from the sun falls off faster than delta velocity ?

3. Has anyone in your camp calculated the electric/magnetic forces on the solar wind ?

4. Please clarify your comment "..Iaboratory observation is considered a completely preposterous..out-of-bounds..", what Specific observations & Eg in relation to solar wind ?
Whydening Gyre
5 / 5 (4) Jan 03, 2016
What we observe is that the solar wind fails to appreciably decelerate even as it passes the Earth's orbit. Solar physicists have proposed a variety of exotic mechanisms to explain it, yet try too hard to ignore the most sensible, from the laboratory, because such an admission would place far too much importance on the role of plasma in large-scale dynamics.

The history for why it turned out this way can be traced back to the widespread belief that space is an empty vacuum.

Hannes-bubbi,
Does it fail to decelerate appreciably for ANY planet?
Steelwolf
4.3 / 5 (6) Jan 03, 2016
Mike, the plasma state of the solar wind is not in question, NASA and JPL as well as others keep track of the temp, density and solar wind speed, basic space weather 101, really, and most of it is electromagnetically charged and operating under heavy magnetic fields, which is exactly WHY we have geomagnetic storms along with the recent CMEs after the most recent larger flares, and what are CMEs but large, denser than normal chunks of solar wind.

Oh yes, this has not been ignored, but truthfully, not everyone arguing 'for' the Electric Universe Theory is on the same page with the actual data. More and more mainsteam science is having to admit that, Yes, there IS a much more energetic plasma-electromagnetic component to space than had been thought in old, dated theories. Articles such as the above one show that there are strong magnetic components to these jets, over hundreds of light years, and THAT is Rather Important as far as FACTS go.
Mike_Massen
2 / 5 (12) Jan 03, 2016
Steelwolf says
Mike, the plasma state of the solar wind is not in question, NASA and JPL as well as others keep track of the temp, density and solar wind (SW) speed, basic space weather 101, really
Yep Really cool, not disputing SW, did I - where ?

Steelwolf claims
...most of it is electromagnetically (EM) charged and operating under heavy magnetic fields (HMF)..
huh, please converge on specific points:-

1. First clarify if you consider SW to be overall; negative, positive or neutral ?
2. Please define your understanding of "EM charged" ie Precise definition ?
3. Likewise re 2. "operating under HMF", you mean Sol if so how much at Earth remains ?

Start with that as your comments have potential for huge divergence, so best to converge on clear issues taken one at a time, ie Term "EM charged", might mean a huge bunch of oddball things re study variance, is it from some recent formal course if so please make it crystal as Gauss' theorem/law applies re EM ?
my2cts
2.3 / 5 (9) Jan 04, 2016
@HA
"fails to appreciably decelerate"
Newton's first law.

Some people even down vote Newton's first law here.
Any deniers on that ? Be the first !
cantdrive85
3.9 / 5 (7) Jan 04, 2016
@HA
"fails to appreciably decelerate"
Newton's first law.

Some people even down vote Newton's first law here.
Any deniers on that ? Be the first !

Some people misapply grade school science around here. Wouldn't gravity be a candidate to slow down the solar wind? That would be the "unless acted upon by an external force" part.

Mike_Massen
1.4 / 5 (9) Jan 04, 2016
cantdrive85 asked
Some people misapply grade school science around here. Wouldn't gravity be a candidate to slow down the solar wind?
Indeed, absolutely correct when you are talking about forces over time but, cantdrive85 why *must* you STOP at "grade school" ?

Surely you did "high school" & learned about limits as pre-requisite to Calculus ?

You seem to not understand paradigm of *escaping* a gravitational field, of course it works perfectly well, we continue to launch satellites & even escape Sol's field altogether & easily Eg Voyager etc so we *know* it works very well indeed :-)
https://en.wikipe...velocity

Its actually simple arithmetic to work out the escape velocity and of course the Calculus to derive it is a bit beyond "grade school" as I am sure you know well...

cantdrive85 added
That would be the "unless acted upon by an external force" part
Glad you thought this but, why stop & not go the whole distance ie Compare EM vs G ?
cantdrive85
3.4 / 5 (5) Jan 04, 2016
You seem to not understand paradigm of *escaping* a gravitational field

You seem to be thinking you've got a good argument since you keep bringing it up. Nobody is questioning escape velocity, leaving a weak gravity field is not an astounding feat. However, matter in excess of the the escape velocity is still experiencing the gravity and should have some deceleration unless something is pushing harder than gravity is pulling. Even the Pioneer spacecraft are decelerating due to gravity;
https://en.wikipe..._anomaly

Glad you thought this but, why stop & not go the whole distance ie Compare EM vs G ?


What, do you mean how EM is 10^39 orders of magnitude more powerful than G? That even the weakest E field will accelerate matter against gravitation. You mean the fact EM is the longest range force, by far? I could bring it up again, but everybody here already knows these facts.
Mike_Massen
1.6 / 5 (7) Jan 05, 2016
cantdrive85 astute
.. thinking you've got a good argument since you keep bringing it up
Since you never quantify re compare EM vs G but, imply EM palpably influences planetary orbits but, there's Nil Evidence or Math !

cantdrive85 says
However, matter in excess of the the escape velocity is still experiencing the gravity and should have some deceleration unless something is pushing harder than gravity is pulling
Sure but, EM negligible, need quantification ?

cantdrive85 says
..Pioneer spacecraft are decelerating due to gravity
https://en.wikipe..._anomaly
Ah good but, *nothing* re EM

cantdrive85 replies when I say
the whole distance ie Compare EM vs G ?
.. do you mean how EM is 10^39 orders of magnitude more powerful than G?
No. Not 10^30 orders, its 10^39 times - the two are VERY different. ie 5 orders is 10,000 times, you exaggerate immensely !

Obviously no, need to integrate over path, EM falls ^3 vs G falls ^2 ?

cont
Mike_Massen
1.6 / 5 (7) Jan 05, 2016
continued @cantdrive85

To clarify/review, if I understand well, from your many jibes/barbs re gravity, relativity & Dark Matter (DM), no doubt you Will correct, your position re ElectroMagnetic force (EM)

1 Arbitrarily discounted & severely avoided by mainstream astrophysics for decades
2 Directly influences all Solar System (SS) planet orbits
3 Significant factor re SS gravitation & beyond
4 THE primary force re all galactic rotation curves, so DM inappropriate
5 Some way, which you will clarify (?), discounts any need for General Relativity at all
6 Demonstrable fact despite, magnetic dipoles sum locally, is irrelevant as EM still persists
over long range (cube law?)
7 ?

Please clarify head-on, best detached means re verifiable Physics OR if there isnt currently verification, experimental methodology

cantdrive85, hope you have come to appreciate the most efficient process arriving at essentials in Physics discussion is convergence via attentive dialectic

cont
cantdrive85
2.6 / 5 (5) Jan 06, 2016
Since you never quantify re compare EM vs G but, imply EM palpably influences planetary orbits

It's difficult to do so, there exists no physical mechanism to explain gravity.
Mike_Massen
1.6 / 5 (7) Jan 06, 2016
cantdrive85 misread & went sideways
Since you never quantify re compare EM vs G but, imply EM palpably influences planetary orbits but, there's Nil Evidence or Math !
It's difficult to do so, there exists no physical mechanism to explain gravity
Wrong, its easy to do so, simply start with Newtonian Gravitation F=Gm1m2/d^2 it works & clearly has done for decades re launches & doesn't need any causal physical mechanism at all to calculate forces. Especially so as General Relativity describes the effect very well indeed.

Your implication electric/magnetic fields influence planetary orbits;-

- has never been show with *any* evidence
- comparative forces, ie EM cube law vs Gravity square law has never even been calculated
- Sol's magnetic field is not measurable on Earth
- Sol & Moon influence tides, Nil evidence of *any* EM effect & Nil calculation either.

Can you address my Q's, as so far there is No Evidence for EU theory at any local SS scale ?

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