Milky way had a blowout bash six million years ago

Milky way had a blowout bash six million years ago
Credit: Harvard-Smithsonian Center for Astrophysics

The center of the Milky Way galaxy is currently a quiet place where a supermassive black hole slumbers, only occasionally slurping small sips of hydrogen gas. But it wasn't always this way. A new study shows that 6 million years ago, when the first human ancestors known as hominins walked the Earth, our galaxy's core blazed forth furiously. The evidence for this active phase came from a search for the galaxy's missing mass.

Measurements show that the Milky Way galaxy weighs about 1-2 trillion times as much as our Sun. About five-sixths of that is in the form of invisible and mysterious dark matter. The remaining one-sixth of our galaxy's heft, or 150-300 billion , is normal matter. However, if you count up all the stars, gas and dust we can see, you only find about 65 billion solar masses. The rest of the normal matter - stuff made of neutrons, protons, and electrons - seems to be missing.

"We played a cosmic game of hide-and-seek. And we asked ourselves, where could the missing mass be hiding?" says lead author Fabrizio Nicastro, a research associate at the Harvard-Smithsonian Center for Astrophysics (CfA) and astrophysicist at the Italian National Institute of Astrophysics (INAF).

"We analyzed archival X-ray observations from the XMM-Newton spacecraft and found that the missing mass is in the form of a million-degree gaseous fog permeating our galaxy. That fog absorbs X-rays from more distant background sources," Nicastro continues.

The astronomers used the amount of absorption to calculate how much normal matter was there, and how it was distributed. They applied computer models but learned that they couldn't match the observations with a smooth, uniform distribution of gas. Instead, they found that there is a "bubble" in the center of our galaxy that extends two-thirds of the way to Earth.

Clearing out that bubble required a tremendous amount of energy. That energy, the authors surmise, came from the feeding black hole. While some infalling gas was swallowed by the black hole, other gas was pumped out at speeds of 2 million miles per hour (1,000 km/sec).

Six million years later, the shock wave created by that phase of activity has crossed 20,000 light-years of space. Meanwhile, the black hole has run out of nearby food and gone into hibernation.

This timeline is corroborated by the presence of 6-million-year-old stars near the galactic center. Those stars formed from some of the same material that once flowed toward the black hole.

"The different lines of evidence all tie together very well," says Smithsonian co-author Martin Elvis (CfA). "This active phase lasted for 4 to 8 million years, which is reasonable for a quasar."

The observations and associated computer models also show that the hot, million-degree gas can account for up to 130 billion solar masses of material. Thus, it just might explain where all of the galaxy's missing matter was hiding: it was too hot to be seen.

More answers may come from the proposed next-generation space mission known as X-ray Surveyor. It would be able to map out the bubble by observing fainter sources, and see finer detail to tease out more information about the elusive . The European Space Agency's Athena X-ray Observatory, planned for launch in 2028, offers similar promise.

These results have been accepted for publication in The Astrophysical Journal and are available online.


Explore further

A black hole story told by a cosmic blob and bubble

More information: A Distant Echo of Milky Way Central Activity closes the Galaxy's Baryon Census, arxiv.org/abs/1604.08210
Journal information: Astrophysical Journal

Citation: Milky way had a blowout bash six million years ago (2016, August 29) retrieved 26 April 2019 from https://phys.org/news/2016-08-milky-blowout-bash-million-years.html
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Aug 29, 2016
See, the Matter is There, it is just at energy regimes we were unable to detect til now.

Aug 29, 2016
So when will the shockwave hit our Solar System and what effects will it have?

Aug 29, 2016
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Aug 29, 2016
Steel,you mean this:

The observations and associated computer models also show that the hot, million-degree gas can account for up to 130 billion solar masses of material. Thus, it just might explain where all of the galaxy's missing matter was hiding: it was too hot to be seen.

More answers may come from the proposed next-generation space mission known as X-ray Surveyor. It would be able to map out the bubble by observing fainter sources, and see finer detail to tease out more information about the elusive missing mass.


Cute semantics isn't it? First they gave up looking for the DM Envelope surrounding this Spiral Galaxy, now they're admitting to losing hope for finding it inside the galaxy. But, HOPE springs eternal as they say.

I never look in the mirror wondering what my 80% Missing Mass of DM looks like, what I see suits me just fine.


Aug 29, 2016
So when will the shockwave hit our Solar System

Since we're about 26k light years from Sagittarius A* the shockwave should hit us in roughly 1.8 million years.

and what effects will it have?

Probably not much.

Aug 29, 2016
In Ph.D. dissertation, Paul LaViolette http://www.etheri...tic.html into Milky Way.

Indeed, yet the merger maniacs will not acknowledge him, who they have mocked for decades. Yet, now it is becoming even more clear that he was right then, and is right now.

Clearing out that bubble required a tremendous amount of energy. That energy, the authors surmise, came from the feeding black hole. While some infalling gas was swallowed by the black hole, other gas was pumped out at speeds of 2 million miles per hour (1,000 km/sec).

LaViolette's superwaves of cosmic rays has affected out climate throughout history, and may have been responsible for massive extinctions. Periodic ejection activity from the central core is central to his model.

Merger maniacs should be embarrassed. Instead, they ignore him, conveniently, pretending this is new news. LOL.

So even today is another bit of predicted evidence now largely confirmed. How many nails?

Aug 29, 2016
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Aug 29, 2016
@BrettC This article points out that this 'Blowout' ended some 6 Million years ago, which means that since it had been going for four to eight million years previous, that for that amount of time the center of our Galaxy shone bright, and there were likely jets visible (which have now expanded into the huge bubbles of extremely hot, ionized gas, discovered in the last few years). Since Visible Spiral of our galaxy is 100K LY across, thus a 50K LY radius, this bubble extending some 20K LY. Consider that our solar system is approximately 2/3rds the distance from center to edge of Visible Disc putting us approximately 27K LY from SagA*. his physical portion of the shock wave takes 300 years to cross a Light Year so, if the data is correct then it should be some 21K yrs before it gets to us, disallowing for ramming-slowdown or gravity and stellar mass effects. Also, since this shock wave is spherical, there is not going to be much effect way out here at 50K LY from the incident.

Aug 29, 2016
Also, this shows that a galaxy can support life while it is going through a Quasar Phase.

Also, what is the actual Speed of the individual particles in this million degree plasma? Certainly there is enough room for the nuclei and electrons to me moving at relativistic speeds and thus have an added mass due to the relativistic effects, even if it is along the terms of 5% that would still be an enormous amount of actual influence, especially since it would be hitting the cooler and slower gas/plasma of the disc itself and thus help to keep it pushed together just from the thermal pressure gradient. That alone negates the need for unseen matter to hold our spiral together, especially if that outer gas/plasma is that hot, then it is going to Push the center together further, eventually feeding the central BH and away we go again, around and around.

Also, on previous post, is only 16K LY from Sag A* so figure 18K yrs for the shockwave.

Aug 29, 2016
Also, this shows that a galaxy can support life while it is going through a Quasar Phase.

Since the shockwave hasn't reached us yet that's a pretty nonsensical statement.

Also, what is the actual Speed of the individual particles in this million degree plasma?

Do you ever read the articles before posting? It says right there...
While some infalling gas was swallowed by the black hole, other gas was pumped out at speeds of 2 million miles per hour (1,000 km/sec).

...if you did you could have anwered your own comment about relativistic speeds/mass. (Hint: The answer is: "No")

But I get it. Constructing your own fantasy is a lot better than reading/comprehension. So carry on...

Aug 29, 2016
The quasars are centers of de-nucleation. By their immense gravitational force they attract the surrounding baryonic matter: there is accretion and absorption as a non-baryonic form.

Quasars are also recycling centers, at the origin of nucleosynthesis, for at a certain moment they reach a critical mass and produce a Big-Bang. The exploding quasar becomes a radiogalaxy, vigorously liberating in two symmetrical jets, and thus remaining in equilibrium, all that has been swallowed in its' last cycle, as well as a number of "grains" of the core of quasar, called " microquasars ".
Link below you can see and manipulate an representation of quasar in 3D :
oviaivo.net/oviaivo-english.html#quasar

Aug 29, 2016
Given our 'Local Bubble' was created by at least one supernova, and there's recent evidence from deep-sea cores that isotope 'fall out' reached Earth, it seems survivable. It may only raise our background 'cosmic ray' flux at high latitudes...

That's at ground level, of course; satellites, space-stations and high-flying jets would suffer. Hopefully Moon, Mars & asteroid bases will be adequately 'dug in' against solar flares and CMEs. That degree of protection should suffice...

At least our solar system is close to the galactic plane; being in the path of the polar jet would surely hurt...

Incidentally, does this outburst affect the Drake Equation ??

Aug 29, 2016
The Light and high speed radiation, X-rays etc had already been hitting us for 4-8M Years, and since it stopped 6M years ago, we are some 5,950K years worth of Non radiation from the central sun (Sag A*), or a lessened amount of visible and X-ray light, the shock wave may never make it this far as pressure is already pushing it back into the vacuum from which the BH already pushed it once, but it is a very much cyclic thing.

The present speed of 1 LY every 300 years means it will be 21K years before the edge of the bubble can Possibly reach us, although prior ones my already be in motion, just not seen. In which case we may and up with increased UV, Infrared, Alpha and gamma particles and enough to possibly overwhelm the solar Magnetic field enough to allow us to be bombarded heavy. Past extinction level events show similar patterns, in that there is a specific time cycle connected to it, and then there is rapid evolution after, which shows a more radioactive environment possible.

Aug 29, 2016
Actually there would be a VERY wide range of speeds possible, 2M miles/hour is not that much, it would be further accelerated by the cyclotron action of the jets themselves, and expanding into Vacuum, so the speed of the Ions in these huge clouds makes a HUGE difference, and they will NOT all be going 2M miles/hr, the basic math of the jets, plasma and the x-ray adsorption and further accelerations due to magnetic fields can produce speeds that give us some of the highest energy gamma rays possible. As far as the rest of the shock wave, it is going to be a rough go tying to move that much gas further out into the galaxy, after all, the push stopped, so what does it naturally do? "So what is this massive shock wave going to do Brain?" "Absolutely Nothing out here Pinky except to try to go back to the black hole and get in, just like it tries to do Every cycle Pinky!"

So if you Want stuff to happen here, then the actual Present speed is the needed number, not the starting one.

Aug 30, 2016
This process repeats regularly - so if some major event did really happen before six billions of years,
uh, 6 million, with an "m". Anyway,
it was rather collision with another galaxy - possibly this one, which has brought the Solar system into Milky Way.
wow, hadn't heard of that... If you click the "continued next page" link there (repeated here), what is the object in one of the spiral arms (right-hand side) that seems to be outshining even the center of the Milky Way in x-rays and gamma rays but is barely (if at all) visible in the optical band?

Aug 30, 2016
Paul LaViolette demonstrated
@zephTROLL
when you write "demonstrated" but then imbed it with a personally owned pseudoscience link, that doesn't "demonstrate" anything in science so much as it proves said person has a "belief in something"

this is one of the biggest points i've tried to make to you in the past, BTW

just because he believes it doesn't mean it's true or real, as demonstrated by his book "Secrets of Antigravity Propulsion" where he doesn't "prove" anything at all, be it antigravity OR secrets from the gov't

source material is important because of validation and the ability to reproduce, etc

if you can't produce empirical evidence that is peer reviewed and reputable then what you're posting is your belief in some other persons opinion (or belief), which is neither science or evidence, but religion, by definition

Aug 30, 2016
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Aug 30, 2016
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Aug 30, 2016
Hmmm. What happens if you fly through million degree gas?

Aug 30, 2016
It's really, really thin, diffuse, whatever, so has a low heat content. Accompanying cosmic rays and wave-riding particles are more of a problem...

Aug 30, 2016
what is the object in one of the spiral arms (right-hand side)...
Ah-ha, NASA has a clickable Multiwavelength Milky Way that gives rough galactic coordinates, and from the Aladin Lite Sky Atlas, I think it's the supernova remnant "Vela XYZ" and at least 4 different pulsars: Vela pulsar, VELA X, V* LN Vel, and HD 73568. No wonder it looks so bright in the gammas and x-rays there...

Aug 31, 2016
Hmmm. What happens if you fly through million degree gas?

At that density? Nothing. (unless you're going really, really fast... but then your problems don't stem from the temperature of the gas)

Aug 31, 2016
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Sep 01, 2016
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Sep 01, 2016
The center of the Milky Way galaxy is currently a quiet place where a supermassive black hole slumbers,


Hawking has recently come out against the existence of BHs. I guess the Author has yet to get the news release, or, thinks he/she is smarter than Hawking.

Sep 01, 2016
http://www.smiths...0958855/

.............."a way out" huh? No Infinite Gravity Wells, no Infinite Densities, and "no" a lot of other things Schwarzschild imagined in his cockamamie Black Hole Math in his Radii. So what's the Author gonna do here? Well, he could consult with Schneibo who has pics of BHs, but he hasn't been around lately, so I guess it falls to Shavo to help the Author out of this predicament?


Sep 02, 2016
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Sep 02, 2016
[
Hawking has recently come out against the existence of BHs. I guess the Author has yet to get the news release, or, thinks he/she is smarter than Hawking.
No he hasn't. http://www.scienc...-paradox

As usual, you don't know what you are talking about.

Sep 03, 2016
The recent article about EMDrive just describes, how its research for Boeing has been classified for ten years. So why would LaViolette would be lying in another cases? The censorship and classification of breakthrough findings just happens all the time..

Read more at: http://phys.org/n...html#jCp
The http://www.ibtime...578716..

This quote from one of the posters best describes him:
It appears that his career began with promise, and that he subsequently became insane.


Sep 03, 2016
Wow. That last post fuxxed up big time! Try again:
LaViolette?; is this the genius who brings us this little gem: http://www.etheri...ic5.html ?

Somebody brought him up on ISF some years back: http://www.intern...t=232799

This post from Buckaroo sums him up pretty well:
It appears that his career began with promise, and that he subsequently became insane.

Sep 03, 2016
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Sep 03, 2016
he borrowed the theory of radiation attributed to him from Russians
Which Russians?
He's probably referring to Yakov Zeldovich and Alexei Starobinsky whom Hawking visited in Moscow in 1973 (Wiki page on Hawking radiation).

Sep 03, 2016
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Sep 03, 2016
LaViolette cited this research only.......

And then concludes with:
As reported in Earth Under Fire, the human race nearly met with extinction at the end of the last ice age during a protracted terrestrial cataclysm that was triggered by the arrival of cosmic rays from an explosion of our Galaxy's core. Moreover by inducing cosmic dust to invade our solar system, this event caused our Sun's flaring activity (and solar wind velocity) to become extremely elevated to the point of initiating a global conflagration. Could the present inhibition of ESP ability during times of Galactic center ascension or times of increased solar wind velocity (increased solar activity) be due to the presence of an unconscious racial memory of this past tragedy?


CRANK!!!

Sep 03, 2016
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Sep 03, 2016
The genetic bottleneck was ~ 70 000 years ago, probably due to the eruption of Toba. The end of the last ice age was NOT 70 000 years ago. And I know of no putative genetic bottleneck for ~ 10 000 years ago!
Christ, he even tries to tie Atlantis in to the end of the last ice age! It would scarcely have been noticeable in the Med (The Black Sea might have been different, but that's another story).
Most scholars who attribute any sort of real events to the Atlantis myth, suggest the eruption of Thera (Santorini), ca. 1600 B.C. as the most likely source.
The guy is a crank, pure and simple. There may well be questions to be answered, but I'd wager a large amount that this bloke won't be answering them.

Sep 03, 2016
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Sep 03, 2016
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Sep 03, 2016
who tend to ignore and dismiss one inconvenient finding after another have no chance in their approach


Which inconvenient findings?
Nothing you've written gives any credence to this guy. He's just a latter day Velikovsky.
How do you know he's involved in "classified" research? I wouldn't let him near the classified ads.


Sep 03, 2016
In 1988 Dr. Abshier visited astronomer Mark Morris in his office to explain to him Dr. LaViolette's Galactic explosion hypothesis. Morris dismissed the idea as having no merit. However, Morris apparently changed his opinion after further observation of the Galactic center because ten years later he was quoted in the November 1998 http://discoverma...Eaxh9k).


Which just confirms Morris as supporting there being a black hole at the centre of the galaxy! Nothing about LaViolette's nonsense. Where is Morris on record as saying he supports LaViolette's nonsense? My guess? It doesn't exist, and was made up by LaViolette.

Sep 03, 2016
genetic bottleneck was ~ 70 000 years ago It did happen many times later.


Not worldwide. There were regional bottlenecks, possibly, and population replacements.

Sep 03, 2016
They will not realize their mistake until we will have cold fusion and magnetic motor plants sold at commercial basis,....


Oh yeah, wouldn't be a crank without some free energy/ new energy angle!


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