Researchers offer possible explanation for lack of radiation flash from gas cloud interaction with Milky Way black hole

Jul 22, 2014 by Bob Yirka report
Comparison of the pv-diagrams from spring 2013 (data already presented in Gillessen et al. 2013b), late summer 2013 and spring 2014 (new data). The blue line corresponds to the Brackett-γ based orbit from Gillessen et al. (2013b), along which the pv-diagram is extracted. We have blended out the range between −660 km/s and +240 km/s to avoid emission from the mini-spiral (Paumard et al. 2004) visible at these wavelengths. The scaling is adjusted in each map individually to optimally show the structure of the gaseous emission; the maps cannot be compared photometrically to each other. Credit: arXiv:1407.4354 [astro-ph.GA]

(Phys.org) —A team of researchers at the Max Planck Institute in Germany has offered a possible explanation for the lack of fireworks during the interaction between a gas cloud and the black hole believed to be at the center of the Milky Way Galaxy. In their paper uploaded to the prepress server arXiv, the researchers suggest that the expected fireworks didn't happen because the gas cloud is actually a dense clump that is part of a continuous stream of matter and because of that it only brushed the black hole rather than gushed into it.

The gas cloud, named G2, was first spotted back in 2011, moving towards Sagittarius A*, the super believed to exist at the center of our galaxy. Scientists expected a sudden surge in X-rays and radio waves and maybe even a possible brightening of infrared light from the site. Instead, as the gas cloud encountered the black hole, nothing much happened. The cloud simply changed shape a little bit with little to no fanfare, leaving scientists who had trained a lot of telescopes on the Milky Way's center, feeling let down. In their paper, the researchers in Germany offer a possible explanation regarding why so little appeared to happen.

G2, the researchers suggest, is actually part of a continuous stream of material that was ripped from the envelope of a star as recently as just a hundred years ago. They note that G1, another spotted over a decade ago, has an identical orbit to G2, and is even in the same plane. They believe both clouds are actually little more than clumps in a much bigger cloud that is essentially a stream of gas that has been traveling towards the center of the Milky Way for a century. And because of that, they suggest, the clumps simply brush Sagittarius A* as they approach and pass by, because of the impact on them exerted by the rest of the stream. If true, it would seem likely that there are other clouds also present in the stream, which are perhaps destined for a rendezvous with Sagittarius A* someday—if so, one of them might produce the fireworks the scientists had been anticipating.

Explore further: A rare crash at the Milky Way's core

More information: The Galactic Center cloud G2 and its gas streamer, arXiv:1407.4354 [astro-ph.GA] arxiv.org/abs/1407.4354

Abstract
We present new, deep near-infrared SINFONI @ VLT integral field spectroscopy of the gas cloud G2 in the Galactic Center, from late summer 2013 and spring 2014. G2 is visible in recombination line emission. The spatially resolved kinematic data track the ongoing tidal disruption. As expected for an observation near pericenter passage, roughly half of the gas in 2014 is found at the redshifted, pre-pericenter side of the orbit, while the other half is at the post-pericenter, blueshifted side. We also present an orbital solution for the gas cloud G1, which was discovered a decade ago in L'-band images when it was spatially almost coincident with Sgr A*. The orientation of the G1 orbit in the three angles is almost identical to the one of G2, but it has a lower eccentricity and smaller semi-major axis. We show that the observed astrometric positions and radial velocities of G1 are compatible with the G2 orbit, assuming that (i) G1 was originally on the G2 orbit preceding G2 by 13 years and (ii) a simple drag force acted on it during pericenter passage. Taken together with the previously described tail of G2, which we detect in recombination line emission and thermal broadband emission, we propose that G2 may be a bright knot in a much more extensive gas streamer. This matches purely gaseous models for G2, such as a stellar wind clump or the tidal debris from a partial disruption of a star.

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User comments : 15

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Scroofinator
1.9 / 5 (17) Jul 22, 2014
So, another model, of another "understood" part of science, is wrong. How many more failures are needed to move past this love affair with Newtonian gravity?
Dr_toad
Jul 22, 2014
This comment has been removed by a moderator.
cantdrive85
3.4 / 5 (35) Jul 22, 2014
Researchers offer possible explanation for lack of radiation flash from gas cloud interaction with Milky Way black hole

Probably because there is no BH there, being BH's are nothing but mathematical constructs envisioned by fanciful astrodolts. The astounding thing is that the standard theory completely fails in just about every prediction but yet there is no shortage of deluded believers. Oh, look, there is one right there. Shows that faith is powerful.

the gas cloud is actually a dense clump that is part of a continuous stream of matter

A continuous stream of matter would constitute an electric current, weird.
Dr_toad
Jul 22, 2014
This comment has been removed by a moderator.
antialias_physorg
3 / 5 (21) Jul 22, 2014
A continuous stream of matter would constitute an electric current, weird.

Erm...So a river constitutes and electric current for you?

I mean: you have been posting about electric universe and plasma and whatnot...but I have to ask: Do you even know what 'electric' means?
Scroofinator
2.1 / 5 (11) Jul 22, 2014
Actually, yes, there is a small current in a river. Any running water has some. As evidenced by the simple children's experiment of splitting tap water into 2 streams and putting the leads of a LED in either stream, after a short time enough charge is built up that it will light the LED.

Funny coincidence that the strength of the flow of water is referred to as current...
no fate
1.5 / 5 (8) Jul 22, 2014
I see Dr. idiot has more insightful remarks on what could have been miscalculated by the mainstream on this one...please your knowledge is blinding!

At least scroof was here to define current for you and the electrical engineering graduate who got confused.
Nik_2213
4 / 5 (12) Jul 22, 2014
You're mistaking cause & effect. See Kelvin's Dropper. http://en.wikiped..._dropper

And 'current' is 'current' because the original investigators of electric phenomena were familiar with hydraulics, so co-opted some of the terminology.

Do not attribute stuff to conspiracy or 'Wondrous Ancients' when 'founder effect' will serve.
no fate
1 / 5 (6) Jul 22, 2014
You're mistaking cause & effect. See Kelvin's Dropper. http://en.wikiped..._dropper

And 'current' is 'current' because the original investigators of electric phenomena were familiar with hydraulics, so co-opted some of the terminology.

Do not attribute stuff to conspiracy or 'Wondrous Ancients' when 'founder effect' will serve.


Specifically, what is the mistake you see here? And how does your link to Kelvins dropper rectify it? The word "current" is used to describe flow in any medium, it's origins aren't the issue here....
cantdrive85
1 / 5 (6) Jul 22, 2014
A continuous stream of matter would constitute an electric current, weird.

Erm...So a river constitutes and electric current for you?

I mean: you have been posting about electric universe and plasma and whatnot...but I have to ask: Do you even know what 'electric' means?


Here I thought the article was about the G1/G2 plasma cloud and it's "extensive gas streamer" identified in the article. The Max Plank scientist referred to it as "a continuous stream of matter" but yet you didn't deem it necessary to correct him.

So: you have claimed to have some kind of education (questionable) and whatnot...but I have to ask: Do you even know what 'context' means?

BTW, did the others make you feel stupid yet with their references to Jr. high science fair projects there "Mr. Electrical Engineer"?
Scroofinator
3 / 5 (4) Jul 23, 2014
Do not attribute stuff to conspiracy or 'Wondrous Ancients' when 'founder effect' will serve.

What is it with you monkeys and all the "conspiracy" talk, it makes one think your all nervous about something. Hmm, perhaps it's the fact that your explanations are running thin.

BTW, did the others make you feel stupid yet with their references to Jr. high science fair projects there "Mr. Electrical Engineer"?

It's not all his fault, schools aren't setup these days to teach critical thinking, just stuff. When people believe everything they're told is "truth" and don't ask questions, they become the typical drone that they're supposed to be.
IMP-9
5 / 5 (5) Jul 24, 2014
Here I thought the article was about the G1/G2 plasma cloud and it's "extensive gas streamer" identified in the article. The Max Plank scientist referred to it as "a continuous stream of matter" but yet you didn't deem it necessary to correct him.


You completely sidestepped the question, answer it. Nothing said in the article contradicts what antialias asks.
cantdrive85
1 / 5 (4) Jul 25, 2014
Here I thought the article was about the G1/G2 plasma cloud and it's "extensive gas streamer" identified in the article. The Max Plank scientist referred to it as "a continuous stream of matter" but yet you didn't deem it necessary to correct him.


You completely sidestepped the question, answer it. Nothing said in the article contradicts what antialias asks.

The phrase I used was the same used in the article as I was referring to that stream of matter, last I checked it wasn't water.
And the question has already been answered, can you even read? Rube.
IMP-9
5 / 5 (4) Jul 26, 2014
The phrase I used was the same used in the article as I was referring to that stream of matter, last I checked it wasn't water.


The article said "a stream of matter" not specific to this feature, you said "that is a current". Last I checked water is matter. You have zero evidence this is one of these mythical cosmic currents, where are the hard tests and simulated observations proving your claim? Oh yeah, they don't exist. But that's the point of EU, to surf a wave of ignorance and assumptions.
yyz
5 / 5 (3) Jul 26, 2014
"You have zero evidence this is one of these mythical cosmic currents, where are the hard tests and simulated observations proving your claim?"

This really gets to the core of the matter here IMP. Just try to find published work that even mentions the G2 cloud from an EU/PC POV and you will find ZERO citations. All the more incredible in light of the fact that since the original discovery paper for G2 was published in 2011, well over a dozen papers have been published concerning the G2 cloud and its interaction with Sgr A*:

http://fr.arxiv.o...112.3264

To date there have been 0 papers published that describe observations of G2 from an EU/PC POV. None. Zilch. Cantdrive may quote blogs, youtube vids, EU pseudoscience sites etc. but the fact remains that there is no published work that describes the interaction between the gas cloud G2 and Sgr A* from a EU/PC POV. It's just the usual handwaving from cantdrive.
cantdrive85
1 / 5 (3) Jul 26, 2014
The article said "a stream of matter" not specific to this feature, you said "that is a current"
.
You're either dumber than a rock (likely), or wish to remain willfully ignorant (obvious).

"In their paper uploaded to the prepress server arXiv, the researchers suggest that the expected fireworks didn't happen because the gas cloud is actually a dense clump that is part of a continuous stream of matter...G2, the researchers suggest, is actually part of a continuous stream of material ...They note that G1, another gas cloud spotted over a decade ago, has an identical orbit to G2, and is even in the same plane. They believe both clouds are actually little more than clumps in a much bigger cloud that is essentially a stream of gas"

You have zero evidence this is one of these mythical cosmic currents,


Yep, as long as you ignore the obvious. It has all the characteristics of the predicted features of said currents;
http://www.plasma...APSS.pdf
RealityCheck
1.8 / 5 (5) Jul 26, 2014
Hi Forum. Just catching up with loose end news items/discussions, and saw the latest exchange regarding the G1/G2 cloud and the overall 'stream of matter' they are 'clumps' in. The thing to be noted is that the stream of matter is surmised to originate from a fully/partially 'disrupted' star's outer layers or deeper. If so, then not only would that stream have started out as being fully/partially 'plasma' state reflecting its erstwhile state as part of a Star's material, but when such a stream is so close to the extreme/hard 'dynamics/radiation' conditions/environment well within the inner galactic core feature/processes, then the extreme gamma/X-ray and collisions scenario would guarantee that these 'clumps' would remain ionized plasma stream/clumps to some degree.

I make no further comment re any other speculations/claims from theory/hypotheses from 'either side'. Just making an observation as to the state the clumps must be in consistent with known information. Bye for now.