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stalhandske 02-Jun-18, 07:48 |
 mo-oneMo-nine |
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CERN I mean, a grain sized BH would gobble Earth pretty fast. But getting to that would be problematic. It would not really eat the world, but shake it apart like a dog with a chicken. The Earth remnants not consumed would fall into orbit, making a ring that rapidly coalesces into a partner moon. Well within a hundred thousand years. But the sun would flame out before the BH reached that size, and we would need at least another order of magnitude of energy to create a BH in the first place. So nothing to fear, and the Higgs Boson rest mass was well worth the risk. |
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Gambling Earth's Future I would gamble the fate of humanity on shorter odds than that, for equally impressive reward. While there are some who would not, we live in MY world, not theirs, thank God. They must learn to accept the fact we will continue learning about our universe, because ignorance has always been far deadlier to our species. Count those killed by dysentery and other microscopic organisms. Knowledge is power. |
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Imaging a Hole Black holes are very small, compared to big stars. We have resolved the disk of only a tiny handful of nearby suns--the last I heard actually only one. So to resolve a black hole ergosphere--especially from as far away as the nearest of any reasonable size--that would be a feat indeed. The smallest black holes are only a bit more massive than neutron stars. So the size has to be pretty comparable--at least for black holes in the 4 solar mass range. The diameter of a 4 solar mass black hole would be about 15 miles. Imaging something in the optical wavelengths that size from a thousand light years--I wish I knew what they were imaging. Sagittarius A* masses roughly four million suns. While I haven't done the math, just looking it up they say this works out to a diameter of 27 million miles. Which seems insanely huge. So I don't really know what it is they are measuring. It is possibly the outside diameter of the accretion disk, as opposed to the diameter of the black hole itself. Or if the thing is rotating, it is possible it is smeared out into more of a disc shape. I don't know. On second thought, the disc seems unreasonable, given that whether the mass is moving or not the gravitational pull ought to be the same equidistant from the center of mass. So disc shaped rents in spacetime fabric would be unexpected. On the other hand, there is inertial frame dragging, that is some kind of thing. Not sure how it ties to gravity. Maybe the accretion disk mass affects the boundary--the event horizon? I would expect the accretion disk to be very hot. We know these radiate a lot of energy in the X-ray spectrum. That's short wavelength light--in the ultraviolet range. A stupid mnemonic for the electromagnetic spectrum: Roman Men Invented Very Unusual X-Ray Guns. Radio, micro (shortwave radio), infrared (heat), visual, ultraviolet, X-ray, gamma rays. |
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Perhaps the Photo of the Century |
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Sagittarius A* That's the one they are doing the photo of, about 30K light years away. Cygnus X1 is only around 1500 ly away, but it is just 4 solar masses, I believe. |
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Whoa |
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LS |
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You are Right |
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My image is on my profile page.Which just shows the Galaxy and Jet. |
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Distance to M-87 Distance to Earth: 53.49 million light years Radius: 60 light years Apparent mass: ~2,400 billion M☉ Apparent size (V): 7.2 × 6.8 moa The figure for the radius is bull shit. I don't know what they are talking about. Interstellar clouds of gas might be 60 light years across--though that would be pretty big. The galaxy COULD be 600,000 light years across, though that is probably too big. 60,000 light years is probably too small, given the mass of the galaxy. Oh, radius--120,000 light years in diameter. Whoever wrote this could have meant 60,000 (sixty THOUSAND) light years radius. But absolutely not a mere 60. |
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M-87 But M-87 is on this side of it, towards us. |
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good |
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Sweet The jet of light you see emanating from the galaxy's core stretches out away from it some tens of thousands of light years. Knowing the magnification--the number of arc seconds of the image--and the distance to M-87 we could roughly calculate the length of the jet. The bright portion of the core is 45 arcseconds across. At 53.5 million light years... tangent (0.0125 degrees) [45 arc seconds] = y/53.5 million ly, where y=diameter of the bright part. I get about 12,000 light years across. The jet is easily that diameter plus the radius, or 18,000 light years. |
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I believe the Milky Way is about 120K light years across, plus or minus a few thousand trillion miles or so. |
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This Monster www.universetoday.com |
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LS; very impressive. |
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Black holes n worm holes |
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LIGO This instrument is the forefront of gravity wave research, and is a phenomenal piece of equipment. Gravity waves displace the arms of the 2.5 mile long arms of the apparatus, stretching and contracting them about one thousandth of the diameter of a proton. We measure that displacement as an interference pattern, translating the gravity waves into sound waves to produce a "chirp." The chirp represents an energy release of utterly stupendous proportions--far and away the most energetically violent events we have ever witnessed. For example, the first collision detected were the gravity waves from two black holes of 29 and 36 solar masses, resulting in a black hole of 62 solar masses. 29 + 36. What this means is the missing mass was bled away in the form of gravity waves. This collision was so powerful the equivalent of multiple earth masses were converted into enough energy to ripple the spacetime fabric. How many earth masses? You can stack a hundred Earths across the sun's diameter. Multiply by a hundred for the cross sectional area--10,000 Earths in a plane. To get the volume multiply by 100 again--a million Earths. But the sun is about a third the density of the Earth, so while it's volume is a million Earths, its mass is a mere 330,000 Earths. However, the difference between the original two black holes and the result was 3 solar masses--or again a million Earths worth of mass. In comparison a stick of dynamite is about one quarter of a pound. So a 20 kiloton nuclear weapon is the equivalent of... 4 sticks to a pound, 8000 sticks to a ton, times 20,000 = 1.6 million sticks of dynamite. We detonated the equivalent of 1.6 million sticks of dynamite 1500 feet above Hiroshima, erasing a good fraction of the city. That came from about 2% of the fissionable mass of roughly 36 pounds of Uranium 235 being slammed together and held in one spot. 1% is 0.36 lbs, 2% is 0.72 lbs. So just under a quarter of a pound of mass converted into energy erased Hiroshima. Less than one pound. Now image the entire Earth--all its air, land masses, oceans, crustal plates, mantle, and core--all 268 BILLION cubic miles of our planet converted into energy. And not just this world, but a million more the same size besides. All that enormous energy tugging on spacetime. No light, no heat, just spacetime waves bleeding away a million Earth's mass of energy... |
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LIGO II NINE SOLAR MASSES of total mass conversion. Whee! The second post in this thread concerned wormholes. The end of a wormhole would look very much like a black hole, but the chirp a wormhole/blackhole merger would make would be noticeably different from a regular BH/BH merger. So we would be able to detect wormhole mergers should such occur. We have detected NS/NS mergers (neutron star), and those are fascinating as well. I believe LIGO is shut down right now for upgrades, but one of that last mergers pushed up into the lower realm of black hole masses never previously detected. We know of LOTS of stellar mass black holes, and lots of galactic gargantua starting in the low millions (our own galaxy's core sports a 4 million solar mass behemoth--a mere pipsqueak among galactic black holes). But we have not detected black holes in the 100 to one million range. There is a black hole mass hole, or gap, and this gap is puzzling. If an advanced civilization created a wormhole and that civilization went extinct, it is possible their wormhole could eventually be absorbed by a black hole, which we would then be able to detect. Relic worm holes, like ships abandoned in the Sargasso Sea swirling into some ocean vortex. If wormholes are a natural phenomenon they don't account for a very large percent of black holes. That percent will vanish away as we detect more and more mergers. I am surprised at how few NS/NS mergers we have seen, given that neutron stars are (or should be) far more common the black holes. |
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LS; I like that Shiva. Very poetic. I don't believe Black holes are wormholes. When they finally detect a worm hole, I'll believe they exist. But i do believe Far more advanced Civilizations exist out in the immense void. Few and far between to be sure. If there are only 5 or so in each Galaxy (average of 200-300 billion stars per Galaxy) And the Number of Galaxies 'so far' is thought to be 2.2 Trillion, then that means there could be, 5x 2,2 Trillion Advanced Civilizations out there in the ''observable Universe''.(there are probably more but let's be conservative). So the chances of encountering one is infinitesimal or greater. But they are out there.Seeking truth. Most candidate Civilizations probably destroy themselves long before they reach that level of advancement. I am speculating of course. But i like to keep my options open when it comes to speculations.. Hell I'm not even sure we understand what Black holes are in the first place. We have some decent theories that's all. Sorry if we disagree. I spend to much time looking through Telescopes. It has a strange effect on ones imagination. For good or ill. ;play very loud;www.youtube.com PS; notice the bearded old man north of center, in the second image? Strange how the mind sees patterns. |
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BH <> WH We will know BECAUSE the wormhole is different from a black hoke--we will know by the chirp which signal we intercepted--a BH/WH merger or just another BH/BH merger, the same way we can distinguish between BH/NS & NS/NS mergers. I don't think we really disagree on much. We agree the universe is incredible, and old. We agree on evolution and the likelihood of other intelligent species both in our galaxy and in other galaxies far beyond. We agree the breathtaking vistas offered by other worlds in our solar system, and the wonders of clouds of interstellar gas spanning light years--nurseries for new stars. We agree it is possible there are other universes besides are own. I think the one key area of disagreement is that this universe appears to be the result of a hot inflationary big bang, while you think otherwise. I've no reason to harp or dwell on that. My position isn't intransigent--once the evidence points away from the hot inflationary big bang I'll drop it like a hot potato. I just think speculation about other universes doesn't do much for us--at least until we can develop some method for detecting them. No other universe scarred ours during its birth, so far as we can tell. That was something Alan Guth searched for. The quantum physicists postulate myriads of bifurcating universes, but aside from really arcane problems that doesn't seem to help us get anywhere. I want to figure out how to realize the universe in which I turn out to be a mega millions lottery winner. |
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Wormholes Yes--I concur. I don't think there are wormholes, but like you will accept them if LIGO says they found one. Of course, they can only find what is (probably) being destroyed. When two neutron stars collide is the result a black hole? I'm going to have to check that out--but I would anticipate yes. And the answer is, "maybe." It turns out two smallish neutron stars merging may form just a bigger neutron star. The process spills a lot of matter-flinging debris clouds of nuclear matter with sufficient energy to result in prodigious nucleosynthesis--I would guess nearly supernova levels of element production. Neutron stars are roughly Earth sized stars. Incredibly compact, given they are essentially really big atomic nuclei. Oh--and link: en.wikipedia.org |
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Ah www.ligo.org Not all that much. Disappointing, really. Somewhere between 300 and 3000 times the mass of Earth. I wish I better knew the elemental distribution of NS/NS nucleosynthesis. How close does it parallel standard supernova nucleosynthesis? |
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correction Just wanted to make my thoughts clearer. I know where you are coming from, and i highly respect that. |
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Parthenogenesis Theoretically, a universe budded off another might contain only one intelligence, or none. It is possible it might not contain more. So if our universe is a sub universe, we could be the only intelligent species. I suspect that is not the case. Also, I can't explain the philosophical reasoning behind the intelligence limit since I did not understand it. |
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Quasar, Quasar, Burning Bright This behemoth is 13 billion light years away, making it the most distant quasar yet found. While it beats the previous record holder by a mere 20 million years, it is also 1.6 billion solar masses, or "very heavy." We have no good idea how this thing could have grown so massive so fast. Also, the rate of star formation is about 200 times that of our Milky Way. So the quasar appears to be causing the collapse of the surrounding gas into new stars--we believe. While the article hints at this, let me spell it out more clearly--astronomers suspect some very different mechanism lead to the formation of this black hole, so early after the universe first came into existence (a bit over just half a billion years--or 8.5 billion years before our world formed. The idea is that vast dense knots of gas may have pulled out of our universe, perhaps. So instead of growing by the merger of stellar black holes (black holes born from massive stars), these came about a different way. We don't have a very good handle on that yet. www.space.com |
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