Event Horizon Telescope reveals magnetic fields at Milky Way's central black hole

December 3, 2015
In this artist's conception, the black hole at the center of our galaxy is surrounded by a hot disk of accreting material. Blue lines trace magnetic fields. The Event Horizon Telescope has measured those magnetic fields for the first time with a resolution six times the size of the event horizon (6 Schwarzschild radii). It found the fields in the disk to be disorderly, with jumbled loops and whorls resembling intertwined spaghetti. In contrast, other regions showed a much more organized pattern, possibly in the region where jets (shown by the narrow yellow streamer) would be generated. Credit: M. Weiss/CfA

Most people think of black holes as giant vacuum cleaners sucking in everything that gets too close. But the supermassive black holes at the centers of galaxies are more like cosmic engines, converting energy from infalling matter into intense radiation that can outshine the combined light from all surrounding stars. If the black hole is spinning, it can generate strong jets that blast across thousands of light-years and shape entire galaxies. These black hole engines are thought to be powered by magnetic fields. For the first time, astronomers have detected magnetic fields just outside the event horizon of the black hole at the center of our Milky Way galaxy.

"Understanding these magnetic fields is critical. Nobody has been able to resolve magnetic fields near the until now," says lead author Michael Johnson of the Harvard-Smithsonian Center for Astrophysics (CfA). The results appear in the Dec. 4th issue of the journal Science.

"These magnetic fields have been predicted to exist, but no one has seen them before. Our data puts decades of theoretical work on solid observational ground," adds principal investigator Shep Doeleman (CfA/MIT), who is assistant director of MIT's Haystack Observatory.

This feat was achieved using the Event Horizon Telescope (EHT) - a global network of radio telescopes that link together to function as one giant telescope the size of Earth. Since larger telescopes can provide greater detail, the EHT ultimately will resolve features as small as 15 micro-arcseconds. (An arcsecond is 1/3600 of a degree, and 15 micro-arcseconds is the angular equivalent of seeing a golf ball on the moon.)

Such resolution is needed because a black hole is the most compact object in the universe. The Milky Way's central black hole, Sgr A* (Sagittarius A-star), weighs about 4 million times as much as our Sun, yet its event horizon spans only 8 million miles - smaller than the orbit of Mercury. And since it's located 25,000 light-years away, this size corresponds to an incredibly small 10 micro-arcseconds across. Fortunately, the intense gravity of the black hole warps light and magnifies the event horizon so that it appears larger on the sky - about 50 micro-arcseconds, a region that the EHT can easily resolve.

The Event Horizon Telescope made observations at a wavelength of 1.3 mm. The team measured how that light is linearly polarized. On Earth, sunlight becomes linearly polarized by reflections, which is why sunglasses are polarized to block light and reduce glare. In the case of Sgr A*, polarized light is emitted by electrons spiraling around lines. As a result, this light directly traces the structure of the magnetic field.

Sgr A* is surrounded by an accretion disk of material orbiting the black hole. The team found that magnetic fields in some regions near the black hole are disorderly, with jumbled loops and whorls resembling intertwined spaghetti. In contrast, other regions showed a much more organized pattern, possibly in the region where jets would be generated.

They also found that the magnetic fields fluctuated on short time scales of only 15 minutes or so.

"Once again, the galactic center is proving to be a more dynamic place than we might have guessed," says Johnson. "Those magnetic fields are dancing all over the place."

These observations used astronomical facilities in three geographic locations: the Submillimeter Array and the James Clerk Maxwell Telescope (both on Mauna Kea in Hawaii), the Submillimeter Telescope on Mt. Graham in Arizona, and the Combined Array for Research in Millimeter-wave Astronomy (CARMA) near Bishop, California. As the EHT adds more radio dishes around the world and gathers more data, it will achieve greater resolution with the goal of directly imaging a black hole's event horizon for the first time.

"The only way to build a telescope that spans the Earth is to assemble a global team of scientists working together. With this result, the EHT team is one step closer to solving a central paradox in astronomy: why are so bright?" states Doeleman.

Explore further: Astronomers poised to capture image of supermassive black hole

More information: "Resolved magnetic-field structure and variability near the event horizon of Sagittarius A*" Science, www.sciencemag.org/lookup/doi/ … 1126/science.aac7087

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wduckss
1.6 / 5 (7) Dec 03, 2015
The diameter of the center of our galaxy is "around 30,000 light years in the north-south direction" (http://www.univer...lky-way/ )
The supermassive black hole has a diameter of ~ 0001 to 400 AU (Wiki)
A light year is 9.4607 × 10 ^ 12 Km
How they manage to see a black hole? Especially is a drawing "dark".

Uncle Ira
3.9 / 5 (11) Dec 03, 2015
The diameter of the center of our galaxy is "around 30,000 light years in the north-south direction" (http://www.univer...lky-way/


I could not find that quote in the Universe place article. It said we are about 28,000 light years away from the center. Also it says the central bulge thing is 10,000 light years in diameter. Were you meaning to put up another article? Or maybe I read that one wrong but I read him twice.
Protoplasmix
5 / 5 (9) Dec 03, 2015
Event Horizon Telescope (EHT) - a global network of radio telescopes that link together to function as one giant telescope the size of Earth.
Very cool :)
wduckss
2.3 / 5 (3) Dec 04, 2015
The diameter of the center of our galaxy is "around 30,000 light years in the north-south direction" (http://www.univer...lky-way/


I could not find that quote in the Universe place article. It said we are about 28,000 light years away from the center. Also it says the central bulge thing is 10,000 light years in diameter. Were you meaning to put up another article? Or maybe I read that one wrong but I read him twice.

"As to the size of the galactic bulge that makes up the core of the galaxy, it's diameter is estimated at around 30,000 light years in the north-south direction. The diameter in the equatorial plane is estimated to be 40,000 light years."
http://www.astrod...axy.html
jsdarkdestruction
5 / 5 (9) Dec 04, 2015
With this result, the EHT team is one step closer to solving a central paradox in astronomy: why are black holes so bright?" states

The article was really good besides that part.
Their is no paradox. The jets do not come from within the event horizon. We are still learning the specifics of the magnetic fields and jet formation but that is hardly some kind of paradox.
Uncle Ira
3.7 / 5 (9) Dec 04, 2015
As to the size of the galactic bulge that makes up the core of the galaxy, it's diameter is estimated at around 30,000 light years in the north-south direction. The diameter in the equatorial plane is estimated to be 40,000 light years."
http://www.astrod...axy.html


Okayeei. I guess I read him wrong. From looking at the pictures I got confused on how wide and tall he is. Thanks, now I know.
cantdrive85
1.6 / 5 (7) Dec 04, 2015
With this result, the EHT team is one step closer to solving a central paradox in astronomy: why are black holes so bright?" states

The article was really good besides that part.
Their is no paradox. The jets do not come from within the event horizon. We are still learning the specifics of the magnetic fields and jet formation but that is hardly some kind of paradox.

The real paradox is that you apparently can't read. The paradox they are referring to is the bright black hole, that should not emit anything due to the magical gravity monster.
thaken
1 / 5 (4) Dec 04, 2015
If space is described as dark energy, and black holes dark matter, dark energy would exist without the essence of time, whereas once the energy occupies a selected area, it cannot reoccupy the area it is already in, causing expansion, and probably there are many variations of dark energy that do not interact with each other expanding. String theory explains 11 of them, so if black holes are dark matter existing in a dark energy universe and the dark matter manipulates dark energy through massive gravitational forces, ripping the strings of dark energies into particle like entities, causing matter / anti matter, particles, "+ - protons / + - electrons, and they frequently smash back into each other, causing high energy waves to escape out the poles. Eventually when the + - particles split, the antimatter side falls into the black hole never to be seen again, explaining where all the antimatter went, while the matter side is expelled into space traveling around the equator of the black
my2cts
3.8 / 5 (10) Dec 04, 2015
@cd
Like any paradox it is based on some conflict between interpretation or intuition and facts. This is what sets it apart from a contradiction. A (hypothetical) black hole may be completely black, while an accretion disk surrounding a very massive compact object may be quite bright.
cantdrive85
1.8 / 5 (5) Dec 05, 2015
@cd
Like any paradox it is based on some conflict between interpretation or intuition and facts. This is what sets it apart from a contradiction. A (hypothetical) black hole may be completely black, while an accretion disk surrounding a very massive compact object may be quite bright.

You should call the dude Doeleman that made the comment and let him know he made an erroneous statement. Give him your explanation, I'm sure it would be news to him.
my2cts
3.5 / 5 (8) Dec 06, 2015
@cd Doeleman surely knows this. He does not need my help, you do as it is only a paradox to the perplexed.
jsdd also correctly explained it.
cantdrive85
1.8 / 5 (5) Dec 06, 2015
With this result, the EHT team is one step closer to solving a central paradox in astronomy: why are black holes so bright?" states Doeleman.


Hmmmm....
viko_mx
1.8 / 5 (5) Dec 06, 2015
The black holes are the brightest objects in the universe according to evolutionist. Again paradox but this is the norm for them. Their next gem is a consolidation of matter in the universe thanks to the gravity, which is not able to stop its expansion. They like to create paradoxes. They believe that are intelligent species that emerged thanks to magic contrary to the physical laws, but reject the idea for more mighty Intelligent being in the universe who create and support order and can control us. For them the the main priority in life is the ego and wishful thinking. They needs GR to justify moral relativism (lawlessness) in society. Therefore they see fictional luminous black holes everywhere in the universe.

viko_mx
1.8 / 5 (5) Dec 06, 2015
Black holes exist in some abstract 3d space without physical properties.
jsdarkdestruction
4 / 5 (8) Dec 07, 2015
Viko, I've already explained it's not a paradox because the jets do not come from within the event horizon. The jets come from the accretion disk.
The rest of what you said is nonsense too. None of the scientists are using it to attack your God nor do they intend to.
You are very paranoid and insecure when it comes to your God.
bschott
1.8 / 5 (5) Dec 07, 2015
Viko, I've already explained it's not a paradox because the jets do not come from within the event horizon. The jets come from the accretion disk.


So the guy in the article says it is a "central paradox" and you disagree....wow, when I explain why something in an article is flawed the scientifically illiterate "1 star" brigade who aren't intelligent enough to comment show up in full force. No doubt the same group high fiving you for saying the above.

They are called polar jets for a reason. The accretion disk is around the "equator".
No one who supports mainstream science can accurately model what we observe and explain it. That is why it IS a paradox.

Personally I was happy to see someone from the mainstream acknowledge this for what it is when viewed through the rose colored glasses of mainstream theory. Thank you Shep.

jsdarkdestruction
5 / 5 (6) Dec 07, 2015
That's not the paradox mentioned in the article. The paradox was specifically "why are black holes so bright". Nothing about why the jets form where they do. It was the popular fallacy paradox of if black holes being bright yet nothing should be able to escape their pull. A paradox easily shown to be false because the beams dont come from inside the event horizon.
my2cts
3.3 / 5 (7) Dec 07, 2015
Black holes exist in some abstract 3d space without physical properties.

There also appears to be one bh located in your brains.
my2cts
2.3 / 5 (3) Dec 07, 2015
That's not the paradox mentioned in the article. The paradox was specifically "why are black holes so bright". Nothing about why the jets form where they do. It was the popular fallacy paradox of if black holes being bright yet nothing should be able to escape their pull. A paradox easily shown to be false because the beams dont come from inside the event horizon.

jsd, a paradox is not false nor true.
jsdarkdestruction
4.2 / 5 (5) Dec 07, 2015
I meant that people claiming it's a paradox is a popular fallacy. It should be
"A paradox whose existence is easily shown to be a false one." Above. Thank you for pointing out my wording flaws.
my2cts
1 / 5 (2) Dec 07, 2015
A paradox is an apparent, not a true contradiction. It is neither false nor true.
In defense of the position of bs, the picture does suggest that the jet originates from the black hole itself.
cantdrive85
2.3 / 5 (6) Dec 07, 2015
They drew their pretty little picture based upon the evidence revealing where the magnetic fields are located.

The jets are correctly located being they are not "seeing" a fictional BH, they are observing a real plasmoid.

http://newenergya...moid.jpg

Once again, the jets and associated magnetic fields are predicted in PC.
Whydening Gyre
5 / 5 (2) Dec 07, 2015
The real paradox is that you apparently can't read. The paradox they are referring to is the bright black hole, that should not emit anything due to the magical gravity monster.

Paradoxically... it doesn't.
It's the interaction of the gravitationally massive BH with "standard" space that generates the magnetic fields, creating said "event horizon", which then, in turn, generates the "bright" radiation...
Consider it a layered approach.
jsdarkdestruction
3.7 / 5 (3) Dec 07, 2015
My2cts, based off what you said and reading definitions of paradox on a bunch of sites I must concur with you. My previous statement was wrong. It is a paradox. An apparent paradox but that doesn't seem to matter if it's an apparent or actual contradiction.
Whydening Gyre
5 / 5 (2) Dec 07, 2015
A paradox is an apparent, not a true contradiction. It is neither false nor true.
In defense of the position of bs, the picture does suggest that the jet originates from the black hole itself.

In defense of the picture, the description begins with " In this artists conception"...
my2cts
1 / 5 (2) Dec 08, 2015
A paradox is an apparent, not a true contradiction. It is neither false nor true.
In defense of the position of bs, the picture does suggest that the jet originates from the black hole itself.

In defense of the picture, the description begins with " In this artists conception"...

"artist's conception" means representation not of data but of ideas and models. The artist pick the colours and the lighting but must faithfully represent the models. Either the illustration is misleading or the jet and the magnetic fields indeed emerge from the black hole.
viko_mx
1.8 / 5 (5) Dec 08, 2015

"Viko, I've already explained it's not a paradox because the jets do not come from within the event horizon. The jets come from the accretion disk."

The theories like fairy tales can not prove anything. They themselves need facts to be accepted as proven. The theory of GR and BB can not rely on facts and these theories do not pursue scientific purposes. The objectives of these theories is disinformation.

In fact no one can go tho the fictional black hole and to prove the GR. This theory can not be proven. There is now need even to mansion the fact that these theories do not deal with real physical objects. This is a sufficient argument for their incorrectness.
Whydening Gyre
5 / 5 (1) Dec 08, 2015
"artist's conception" means representation not of data but of ideas and models.

Ergo. not actual data driven. Artistic interpretation/visualization.
Either the illustration is misleading or the jet and the magnetic fields indeed emerge from the black hole.

easy answer - what does the DATA say...
Whydening Gyre
5 / 5 (6) Dec 08, 2015
The theories like fairy tales can not prove anything. They themselves need facts to be accepted as proven. The theory of GR and BB can not rely on facts and these theories do not pursue scientific purposes. The objectives of these theories is disinformation.

In fact no one can go tho the fictional black hole and to prove the GR. This theory can not be proven. There is now need even to mansion the fact that these theories do not deal with real physical objects. This is a sufficient argument for their incorrectness.

This statement could also be applied to the "Theory" of god...
Whydening Gyre
5 / 5 (1) Dec 08, 2015
And if you take a CLOSE look at the picture, you will see the magnetic field lines and polar jets don't begin AT the "surface" of the BH, but rather a miniscule distance ABOVE the surface.
my2cts
1 / 5 (2) Dec 09, 2015
WG are you serious ? The artist should represent a model. That is the part in the sentence you quote from me, a bit further on.
my2cts
1 / 5 (2) Dec 09, 2015

The theories like fairy tales can not prove anything. They themselves need facts to be accepted as proven.

How dare you criticize fairy tales? A fairy tale is still better than a delusion like yours.
Whydening Gyre
1 / 5 (1) Dec 09, 2015
WG are you serious ? The artist should represent a model. That is the part in the sentence you quote from me, a bit further on.

quick question. Isn't a model supposed to represent the data?
To me, if they don't exactly match up, someone said, "ahhh... submission deadline coming up - close enough..." :-)
my2cts
2.3 / 5 (3) Dec 10, 2015
quick question. Isn't a model supposed to represent the data?

This model is beyond the resolution of present tools but still it should illustrate what the researcher believes plausible. The picture seems misleading and indeed it misled bs. He is easily misled by the way, I'll give you that.
Zzzzzzzz
2.3 / 5 (3) Dec 10, 2015
The diameter of the center of our galaxy is "around 30,000 light years in the north-south direction" (http://www.univer...lky-way/

Either the scale in the figures or else the distances quoted are off on your linked page - the 28,000 ly distance is nearly twice the central bulges 40,000 ly diameter..... and the estimated age of the galaxy is a mere 800 million years? The earth has been around longer than the Milky Way? Maybe astrodigital needs some checking.......
Whydening Gyre
5 / 5 (1) Dec 11, 2015
WG are you serious ? The artist should represent a model. That is the part in the sentence you quote from me, a bit further on.

Yes, I am.... And DON'T call me Shirley...

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