Milky Way Black Hole Could Reignite 117
sciencehabit sends us to Sciencemag.org for an account of a survey of nearby galaxies that points to the possibility that once-quiescent galactic nuclei could wake up and become active again. If the Milky Way's dormant black hole should become active, it could be bad news for life on Earth (and elsewhere in the neighborhood). The paper (PDF) is up on the arXiv.
Protect yourself (Score:5, Funny)
You may want a tin foil codpiece, too.
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*groan*
oblig. (Score:3, Funny)
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Re:oblig. (Score:5, Funny)
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The difference between the two, on my end, is that I've watched FF at least once since buying it. I have started Insurrection twice, but never got more than 30 minutes into it. It was that bad.
Please note that the only reason I own either one is that I had two gaping holes in my Trek collection that had to be filled, regardless of how dirty I felt when I bought them.
Final Frontier pr
oblig. retort (Score:2)
Further, that you've only ever made it through 30m of the video? Twice?
Sure you aren't talking about another industry?
Just saying...
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http://en.wikipedia.org/wiki/Pierson's_Puppeteer [wikipedia.org]
but they don't bother with spaceships either they use planets....
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Eye muss bee knew hear (Score:4, Informative)
I don't think we have anything to worry about. Nothing to see here (and if it happened, nobody to see it)
Re:Eye muss bee knew hear (Score:5, Informative)
That's not what the article says:
It's not understood what is causing the black holes to become newly active, because in most cases there is no evidence of collisions or mergers.
It's not just definite, it's *in*definite. (Score:2)
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Clearly it's the dark matter that nobody has figured out where it is or where it's going that's colliding with all these black holes making them quasars.
In theory a super large gravity well that's tightly compressed shouldn't change into a quasar with no reason. After-all with no impact, that would require matter escaping the singularity...
But FWIW i doubt it wou
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"Current measurements suggest the Andromeda Galaxy is approaching us at 100 to 140 kilometers per second. The Milky Way may collide with it in 3 to 4 billion years, depending on the importance of unknown lateral components to the galaxies' relative motion. If they collide, it is thought that the Sun and the other stars in the Milky Way will probably not collide with the stars of the Andromeda Galaxy, but that the two galaxies will merge to form a single elliptical galaxy over the course of
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I had surgery last Thursday to correct the detached retina, a vitrectomy [wikipedia.org]. From the Wikipedia article:
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Nothing to see here, please move along...
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> turn into a quasar is for the galaxy to collide with another galaxy.
You didn't RTFA very well. The point is that they have found galaxies whose black holes have reignited without there being any evidence of a collision.
Re:Eye muss bee knew hear (Score:5, Interesting)
As matter accelerates and gets closer and closer to the event horizon, particles begin bouncing into each other, like outside that one Who concert. Except in this case, instead of being crushed to death (as those concert-goers), centripetal force slings matter towards the poles of the hole with enough energy to achieve escape velocity. This creates a massive beam of ultra-high energy particles that would be very bad for your health. Well, two beams (one "up" and one "down"), but you get the idea.
Soo close (Score:2)
Re:Eye muss bee knew hear (Score:5, Funny)
It isn't a galactic collision. It's just the reunion tour for Disaster Area.
Speaking as user Slartibartfast... (Score:2)
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So, since these huge frickin' ... er... death beams ... exit via the poles, wouldn't most of the planets in our galaxy be relatively safe from irradiation? It seems that the galactic black hole would rotate on the same plane as the rest of the galaxy. So to us it'd be like those giant search lights they point to the sky at Wal-Mart openings.
I wonder if you could accomplish the same thing with micro black holes. That'd be a hell of a weapon, although it'd give new meaning to "Back blast area clear!"
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That's no black hole. It's a space station.
Well, at least we know they have increased the range and power of its death laser.
InnerWeb
Relitively safe isn't all that safe. (Score:2)
Unfortunately, the beams are so energetic that, this close to them, the percentage that scatters off the dense stars clusters and clouds near the core is still an issue.
I'd think of it as the difference between becoming a steam explosion and burning organics in a steel mill from having a crucible of molten iron dumped on you and being burned into a crispy
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How else to explain it?
Reading comprehension requires practice (Score:2)
Actually, the main message I get from the article is how complex the universe is, and how little is known, even by the most knowledgeable, about how these mechanisms work.
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Re:Eye muss bee knew hear (Score:4, Funny)
Feed Me (Score:4, Informative)
Our galaxy's black hole, Sagittarius-A, is not considered active, although it does have some weak emissions, primarily at harmless infrared and radio wavelengths consistent with a very small accretion disc. The nearest star to the black hole is estimated to be about 70 times as far away from it as it would need to be for the gravitational forces to remove significant amounts of material from the star. It also has an orbital period of 15 years, so it would take a long time and a significant perturbance to fall significantly close. It doesn't seem likely at all that it would become active in the foreseeable future.
Of course traffic is heavy near it Fermi Paradox? (Score:2)
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Darn, and I never EVER rtfa, but the summary made it necessary. So for my fellow slashdotters who hate to RTFA, what they mean by "reignite" is to turn into a quasar. The way the black hole could turn into a quasar is for the galaxy to collide with another galaxy.
I don't think we have anything to worry about. Nothing to see here (and if it happened, nobody to see it)
Obviously there is something to see here. Us. Our sun was a member of a galaxy that was absorbed by the Milky Way. The evidence is in the fact that we do not orbit the center of this galaxy in the plane of its arms, but rather perform a wave-like motion alternatively above and below the center plane, passing through the plane in between peaks. A galactic collision could produce the effect noted in TFA, while simultaneously increasing interstellar gas and dust cloud densities, protecting the outer stars fro
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Obviously there is something to see here. Us. Our sun was a member of a galaxy that was absorbed by the Milky Way. The evidence is in the fact that we do not orbit the center of this galaxy in the plane of its arms, but rather perform a wave-like motion alternatively above and below the center plane, passing through the plane in between peaks. A galactic collision could produce the effect noted in TFA, while simultaneously increasing interstellar gas and dust cloud densities, protecting the outer stars from the radiation produced (as well as forcing new star production)
Yeah, this was in a slashdot story awhile back I think. It was pretty quickly debunked by Bad Astronomy: [badastronomy.com]
[Opening paragraph in above link.] Note: I generally don't do a thorough debunking of pseudoscientific nonsense on the blog, and instead relegate that to the main site. But I decided to do this on the blog, knowing that more people would read it than if I put it on the main site and linked to it from the blog. So here it is. Bon appetit.
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So that's what Elvon [paganlibrary.com] was talking about!
The next extinction event? (Score:2)
And the similar hypothesis about the layer of enriched iridium in rocks formed at the boundary between Cretaceous and those of the Tertiary periods and the associated extinction event ... 65.5 million years ago.
Could that suggest an alternative to the "impact from an asteroid or comet" hypothesis? Could
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Oblig overlord post (Score:1, Offtopic)
I am building a ringworld (Score:4, Funny)
Step 1:
- invent scrith
Step 2:
- build Ringworld
Step 3:
- profit (sell real estate)
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So massive core explosions delivering a huge radiation wave are expected. Step 1: - invent scrith Step 2: - build Ringworld Step 3: - profit (sell real estate)
Dear Sir and/or Madam:
Good Day. My name is Jack Brennan. You may call me Brennan-monster. I am writing on behalf of my Protector brethern. This letter constitutes a cease and desist notice. You have been publishing our trade secret, that is, our business plan. Please remove said plan from you website at once or face litigation.
Sincerely yours, Jack Brennan
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I am civilised, after all. I'm a Belter, not a lawyer.
Jack Brennan.
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We Protectors stick together.
Now go away, or someone with Genetic Luck will come along and ruin this conversation by making it so that any further dialog entered into it will only work out in their favour.
Jack Brennan
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Rich Mann.
Have you read Down in Flames?
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Okay, so this isn't relevant to my day-to-day life (Score:3, Insightful)
SO - not unlike the assertion (for example) that there's a large asteroid with Earth's name on it, this research seems to indicate that perhaps we should start studying this phenomenon now even if there's nothing we can do about it now. After all, much of our modern technology was understood to be impossible/impractical as little as a century ago; if we start looking now, perhaps we can devise a mechanism for the preservation of our species before we need it. Then again, when has humanity ever shown that much foresight?
Re:Okay, so this isn't relevant to my day-to-day l (Score:2)
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You DO know that particles with much higher velocities and energy levels than the LHC could ever produce interact with other particles every second in the upper atmosphere of Earth, and that no planet devouring quantum black holes have appeard and devoured the Earth, nor have any "strangelets" converted the Earth to its component bits.
Oh, wait. Apparently no, you DON'T know.
Stop listening to Art Bell (or whoever is in the chair at his radio program these day
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You DO know that such collisions involve one particle with high velocity impacting a particle at rest (relatively speaking) with respect to the earth, making the collision products scatter like billiard balls after a good break and thus taking them away from the planet in short order? As opposed to colliding two streams with o
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It seems to me that a significant fraction of the collisions would produce particle showers pointed towards the ground. Even if 99% of the "evil bits" have momenta that don't allow them to settle into the earth, there's still a lot of evil bits (produced by incident particles with energies 10^4-10^6 times more energy than the LHC) over the last 4+ billion years that haven't des
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Sure. But the idea is that the particles so produced would be zipping along rapidly due to the momentum imparted by the collision, and would go right through the planet with a small chance of reacting with anything.
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Apparently, that "small chance" you posit is so small, as to be effectively zero.
Thanks for playing! Vanna has some lovely
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Uh, yes. So what? No one was talking about neutrinos.
In 4.5 billion years or so, I suspect there have been few if any collisions between particles with high but opposite velocities. How often does one high energy cosmic ray particle knock into another going the opposite direction?
Yes, lots of collisions between hi
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If neutrinos can and do interact with particles...
Uh, yes. So what? No one was talking about neutrinos.
It's called an analogy. Much like your very lame pool ball analogy. Except mine makes sense.
If neutrinos, virtually massless particles with no charge, can interact with matter to an extent they are routinely detectable, then these super high energy particle generated in the upper atmosphere, it's likely in that in 4.5 billion years, at some point, that quantum black holes have
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No, it's called a non sequitur. Neutrinos, from man-made reactions or from natural ones, have not been seen to exist traveling at any velocity besides a whisker away from c. All neutrinos are equal.
The question here is not just whether weird dangerous particles could form, but with what velocity relative to the earth. If they can exist at all (and I'm not saying that they can) a non-evaporating micro black hole or a stranglet or a monopole at rest with respect to the earth is a
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YOU WIN!
I didn't say "disprove existing theory" . . . (Score:1)
HUGE difference.
Oh noes! (Score:2, Funny)
Quick, invade something, anything!
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Don't be so quick to invade! I say, we develop manned space travel so that we may send some of our elected leaders to meet with the black hole in its homeland of the galactic nucleus to discuss the situation.
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So what you're saying is we fight them over there so we don't have to fight them over here. Brilliant! You build the spaceship, I'll build the giant magnetic yellow support-the-troops ribbon. (Well, I won't really *build* it so much as I'll outsource the building of it to China).
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20 to 40%? Reignite? (Score:5, Insightful)
Re:20 to 40%? Reignite? (Score:4, Informative)
Haven't you watched CSI: Stellar Cartography Unit?
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The galactic core could be exploding? (Score:5, Funny)
Still not getting it ... (Score:2)
So, a quasar is an energetic black hole? Or it's kinda like a black hole, but different, and with more spinning and less dark?
What is the black hole "doing" when it's not spraying high energy particles every where? What happens to turn a black hole into a quasar short of two colliding galaxies? We're now sure that there is a black hole in the center of all-if-not-most galaxies seems to be implied by thi
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Quasars are an effect created by the supermassive black holes at the centre of each galaxy, these black holes consume tremendous amounts of mater (something like 10 sun masses a year) the more solar masses they consume the brighter they are. Obviously there is only so much material than can be pulled in by the supermassive black hole, eventually all the material is either ejected as high intensity engery (the quaser pulses we can observe) or consumed by the black hole.
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The scary part (Score:2)
The night sky would be pretty though.
maybe it already has (Score:3, Insightful)
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Date Set (Score:1)
No evidence for "re-ignition" (Score:4, Informative)
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Black hole eats everything in easy reach, goes dormant. New source of fuel builds up in the neighborhood, black hole starts eating again, and the galaxy "reignites".
Axis of Rotation (Score:2, Interesting)
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Here's a theory (Score:3)
We detect the presence of black holes at galactic centers by observing the stars whirling around said galactic center at high rates of speed, right? All those stars whirling around have mass, therefore, gravity. Other stars moving around, maybe not as near to the galactic center, also have gravity. All this movement and such may attract, due to gravitational pull, a cloud of gas somewhere nearby. Slowly it gets pulled by the stars' gravity, until it gets into the gravitational pull of the black hole. Quasar'd!
A Message From the Milkway (Score:1)
On an Unrelated Note... (Score:1)
Just you wait... (Score:2)
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Nope. That's entirely speculation. We do not know the transverse velocity of the Andromeda galaxy, only the velocity along the line of sight. No way to tell if it's going to hit or not.
What to do? (Score:2)
stranger than fiction? (Score:2)
It seems like I read a sci-fi short story along these lines. Only I don't think it was a "black hole reignition". It was a "sun-like" object, only on a much larger scale. Scientists had verified it's existence and determined that, coincidentally, the first light from that object would soon reach earth (I don't know how they discovered it before the light from it reached us, but that's beside the point). Anyway, everyone's watching waiting to see this amazing new thing when it appears ... and it burns ev
The ORI are coming and need the black hole to powe (Score:2)
We're probably safe (Score:2)
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I mean, sure, we may still not care if Bush manages to trigger another world war by nuking Iran, but what are the odds of that happening?
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And it may have already happened, so go ahead and have that extra dessert.
-science nerd, dessert lover
Wrong. We are ~26,000 LYs from the galactic core. (Score:2)
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