Cosmic filament probes our galaxy's giant black hole

Cosmic filament probes our galaxy’s giant black hole
A radio image from the NSF’s Karl G. Jansky Very Large Array showing the center of our galaxy. The mysterious radio filament is the curved line located near the center of the image, & the supermassive black hole Sagittarius A* (Sgr A*), is shown by the bright source near the bottom of the image. Credit: NSF/VLA/UCLA/M. Morris et al.

The center of our Galaxy has been intensely studied for many years, but it still harbors surprises for scientists. A snake-like structure lurking near our galaxy's supermassive black hole is the latest discovery to tantalize astronomers.

In 2016, Farhad Yusef-Zadeh of Northwestern University reported the discovery of an unusual near the center of the Milky Way Galaxy using the NSF's Karl G. Jansky Very Large Array (VLA). The filament is about 2.3 light years long and curves around to point at the , called Sagittarius A* (Sgr A*), located in the Galactic center.

Now, another team of astronomers has employed a pioneering technique to produce the highest-quality image yet obtained of this curved object.

"With our improved image, we can now follow this filament much closer to the Galaxy's central black hole, and it is now close enough to indicate to us that it must originate there," said Mark Morris of the University of California, Los Angeles, who led the study. "However, we still have more work to do to find out what the true nature of this filament is."

The researchers have considered three main explanations for the filament. The first is that it is caused by high-speed particles kicked away from the supermassive black hole. A spinning black hole coupled with gas spiraling inwards can produce a rotating, vertical tower of that approaches or even threads the event horizon, the point of no return for infalling matter. Within this tower, particles would be sped up and produce radio emission as they spiral around magnetic field lines and stream away from the black hole.

The second, more fantastic, possibility is that the filament is a , theoretical, as-yet undetected objects that are long, extremely thin objects that carry mass and electric currents. Previously, theorists had predicted that cosmic strings, if they exist, would migrate to the centers of galaxies. If the string moves close enough to the central black hole it might be captured once a portion of the string crosses the .

The final option is that the position and the direction of the filament aligning with the black hole are merely coincidental superpositions, and there is no real association between the two. This would imply it is like dozens of other known filaments found farther away from the center of the Galaxy. However, such a coincidence is quite unlikely to happen by chance.

Cosmic filament probes our galaxy’s giant black hole
A radio image from the NSF’s Karl G. Jansky Very Large Array showing the center of our galaxy. The mysterious radio filament is the curved line located near the center of the image, & the supermassive black hole Sagittarius A* (Sgr A*), is shown by the bright source near the bottom of the image. Credit: NSF/VLA/UCLA/M. Morris et al.
"Part of the thrill of science is stumbling across a mystery that is not easy to solve," said co-author Jun-Hui Zhao of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "While we don't have the answer yet, the path to finding it is fascinating. This result is motivating astronomers to build next generation radio telescopes with cutting edge technology."

Each of the scenarios being investigated would provide intriguing insight if proven true. For example, if the filament is caused by particles being ejected by Sgr A*, this would reveal important information about the magnetic field in this special environment, showing that it is smooth and orderly rather than chaotic.

The second option, the cosmic string, would provide the first evidence for a highly speculative idea with profound implications for understanding gravity, space-time and the Universe itself.

Evidence for the idea that particles are being magnetically kicked away from the black hole would come from observing that particles further away from Sgr A* are less energetic than those close in. A test for the cosmic string idea will capitalize on the prediction by theorists that the string should move at a high fraction of the speed of light. Follow-up observations with the VLA should be able to detect the corresponding shift in position of the filament.

Even if the filament is not physically tied to Sgr A*, the bend in the shape of this filament is still unusual. The bend coincides with, and could be caused by, a shock wave, akin to a sonic boom, where the blast wave from an exploded star is colliding with the powerful winds blowing away from massive stars surrounding the central black hole.

"We will keep hunting until we have a solid explanation for this object," said co-author Miller Goss, from the National Radio Astronomy Observatory in Socorro, New Mexico. "And we are aiming to next produce even better, more revealing images."

A paper describing these results appeared in the December 1st, 2017 issue of The Astrophysical Journal Letters.


Explore further

Hubble gazes into a black hole of puzzling lightness

More information: Mark R. Morris et al. A Nonthermal Radio Filament Connected to the Galactic Black Hole?, The Astrophysical Journal (2017). DOI: 10.3847/2041-8213/aa9985 , On Arxiv: https://arxiv.org/abs/1711.04190
Citation: Cosmic filament probes our galaxy's giant black hole (2017, December 20) retrieved 25 June 2019 from https://phys.org/news/2017-12-cosmic-filament-probes-galaxy-giant.html
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Dec 20, 2017
Sure looks like a magnetic field thread to me. That doesn't mean that is actually what it is, but I would suspect that more exotic theories will be disproved. You heard it here first folks!

Dec 20, 2017
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Dec 20, 2017
"Cosmic filament probes our galaxy's giant black hole" What a setup for crude humour.

Dec 20, 2017
The observable bias for the theoretical (plasma) model over the empirical observations is a remarkable social phenomenon to observe. And you either plainly see it, or the bias apparently has you.


Astute observation there Chris, but you left a word out. ;-)

I would love for it to be a cosmic string, but the odds are probably remote.
Theoretically you can use cosmic strings to create closed time-like curves, permitting time travel.
Very theoretical, but so cool.

http://www.anders...ngs.html

Your best bet is to fire two infinitely long cosmic strings past each other at very high speeds, then fly your ship around them in a carefully calculated figure eight. In theory, you would be able to emerge anywhere, anytime!

Dec 20, 2017
If your theory is wrong and there only exist the field centers, called charge, then there are no particles and the attractive force of the very large conglomeration would not allow escape without some matter anti-matter contraption to give enough velocity; therefore, suggest it is a hyper-light stream. However, referring to the sinusoidal wrinkle within a charge's field, suggest within any conglomeration the speed of charge is constant and equal to c. That is, some relative motion is required. Recall lambda nu = c and the sinusoidal is due to charge motion; then, 2Pi r/T = c then 2Pi r = lambda? But we have only current for a stream! Nor have we reconciled the speed of q or light!

Dec 20, 2017
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Dec 20, 2017
This infers that what we see, i.e. the sinusoidal field, represents what motion?

Dec 20, 2017
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Dec 20, 2017
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Dec 21, 2017
It's readily apparent that, given the three choices, the plasma ignoramuses don't know the first thing about real plasma physics.

Dec 25, 2017
If scientists are certain that there is a big black hole in the center of the galaxy, it's no problem to find out what's going on there. The black hole fucks on the principle of critical mass and gravity around its center. That is why the surrounding matter in any form moves towards the black hole, and what is seen as a filament of great length is the cloud of gases that was thrown off by the explosion of the supernova, and this happened outside the critical radius around BH. When the gravitational field BH becomes less than the gravitational field of the rest of the galaxy, there appears a "clean" space in which there is no matter to gather in the crowds of mass, and that is the space through which the light passes without obstacles, and the spectrum of this light is homogeneous it can be that filament.

Dec 25, 2017
"Cosmic filament probes our galaxy's giant black hole"
How can one NOT snicker at that...?

Dec 28, 2017
In the universe there is a sequence of unfolding of the process of forming matter and from it all forms of celestial bodies, from the formation of subatomic particles to clusters of galaxies. The black hole is not in the tomnon of the formation of celestial bodies, because it has the task of transforming matter back into the form of Aether from which matter forms. If this sequence of processes is not known, nothing can be predicted or understood.
The basic processes are: the formation of the quark gluon plasma from which a magnetor is formed, from it in the order of: quasars, pulsars, neutron stars and supernovae. After the explosion of the supernova, chemical elements, gases, clouds of gases, sun and stars, planets and other celestial bodies are formed.
A black hole is a "bucket" for the processing of matter in Aether, or it's a recycling site in Aether.

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