The interesting thing is, that this scenario was very well expected and calculated very often (even given students as their homework assignments). Albert Einstein's General Relativity is now more than 100 years old, and the theoretical physicists have long pondered about the equations and put them to new boundary conditions to see what they will predict. And then astronomers have searched the sky for hints if their predictions hold, or if they have missed something important.
So in a certain way, this picture is everything else but surprising. The biggest surprise is that there were no surprises. The Black Hole at the center of M87 behaves exactly as predicted by General Relativity. The astronomers got exactly what they were searching for.
That's what the observations tell us. We have a disk whose upper side moves away from us. Thus it is not very bright. The lower side moves in our direction, and inbetween we have a space which doesn't emit any light at all.
When we have a star with 200 times the mass of the Sun, we can calculate the pressure at the core of the star. And then we find out that the pressure will be high enough to fusion even large atomic nuclei up to Iron-56. Thus from the mass of the star, we can calculate, how much fusion will happen, and how much energy that will release. And we find out that it's not a linear relation. A star double the mass of the Sun doesn't shine twice as much, it shines much brighter, as the higher pressure in its core allows fusion processes to go on much faster, and the star is able to fusion larger atomic nuclei.
In the end, we have a pretty good model which puts surface temperature, mass, brightness and lifetime of a star in a single formula. And it tells us, that large stars 10 to 20 times the mass of the Sun will burn through their fusionable material in very short time (1 to 10 million years). Stars even heavier will be unstable, as their emitted energy is not enough to keep the outer shells of the star from falling down into the core, heating it up even more and causing further fusion processes to start, which in turn will cause an explosion of the star. It gets much brighter, pushes its outer shells into space and then cools down, until the remaining star contracts again under its own weight, causing the core to heat up again. Thats why stars of the size of 80 to 200 times the mass of the Sun are called LBVs, Luminous Blue Variables. Because of their heat, they shine in a blue light, and they constantly blow up, reach their peak of brightness, explode, cool down, contract and heat up again.
Stars much larger would be so unstable, that they don't live long enough to be even called stars. They will just collapse under their own weight and turn their core into a neutron star immediately, as the pressure at their core is strong enough to destroy all the electron shells, and push the electrons into the cores, turning protons into neutrons. The energy released will pushing the complete outer regions of the stars into space in a big explosion.
We are not talking 4,000 here. We are talking 4,000,000,000 times the mass of the Sun (the actual measurents from the Black Hole imagining put the estimate further up to 6,500,000,000 times the mass of the Sun).
The largest stars we know so far have masses of around 200 times the mass of the Sun, e.g. Eta Carinae. Eta Carinae has about 150 to 250 times the mass of the Sun, but it shines between 1,000,000 million to 5,000,000 million times brighter (the brightness actually fluctuates).
Here is a picture of M87 a.k.a. NGC 4486. It's not as if M87 was a totally unknown object before. You can see the large beam ejected from the center of the galaxy. It's about 5000 light years long and is caused by the magnetic field of the rotating Black Hole inside the galactic core of 87. The picture was taken by the Hubble Space Telescope (HST).
From the movement of stars in the center of M87 you can calculate the mass of the center. The movement you can tell from the Doppler effect of their light. If they are moving to us, it is slightly shifted to the blue. If they move away from us, the light is redshifted. That's how you can tell the speed of the stars when circling the galactic center. From the distance to the center, you can tell the orbits. With the orbits and the speed, you know how much mass they are circling, because you can calculate the force that keeps them on their orbits. And when you get a mass of at least 4 billion times the mass of the Sun, you gotta ask which object has so much mass, especially if you don't see the light equivalent of 4 billion stars in the galaxy's center.
2. and 3. are related. Yes, the data is sparse and error prone, and yes, that's why collecting all the date and weeding out data, that has errors, took so long. The main problem was that the software to analyze the data had to be developed first, and there were several teams independently of each other developing software. The image you see now is basicly the image all teams agree upon. The images the teams created each had more detail though.
And we are talking about radiotelescopes here. What you get is a signal from an antenna, and you have to recalculate the sources of the different waves the antenna recorded. The datapoints are just long lists of energy measurements from the different antennas.
We knew beforehand that M87 (a large eliptical galaxy about 55 million light years away) had a supermassive Black Hole at its center. There were estimates of its size from redshift measurements of the movements of the galaxy's center. Thus this is not a discovery we stumpled upon, this was a carefully selected target, and there were expectations beforehand how the picture should look like. A physicist who wrote his doctorial thesis on how a picture of a Black Hole should look like, gave a speech three month ago (albeit in German): Andreas Mueller: Foto eines Schwarzen Loches.
An optical device is just some image generator using waves in the visual part of the spectrum. Even a photography is not actually making an image, it is just using waves to change the chemical properties of some compounds, and then you need other chemical compounds to make the changes visible to the human eye. With radar telescopes, you either use the waves to change the geometry of an eletron beam in a CRT, or use computing power for the same effect.
Even the human eye just uses waves to change the stereochemical properties of some molecule (it turns 11-cis-Retinal into all-trans-Retinal, to be exact, which is the same molecule, but with a different bend in space). Depending on the protein connected to the Retinal (it's called an Opsine), you need different wavelengths for the effect to happen. Then the resulting receptor potential is added up with those of of the neighbouring cells, and about 200 cells send a summary signal via nerve fibers to the brain for further processing.
You could say that the Standard Model predicted it, both the Higgs Boson and the non-discovery of anything else. For the next few orders of magnitude of Energy, there is nothing but recombinations of the known particles.
It would have been very interesting if for instance, the Higgs Boson also comes in generations like the leptons, or if we had something like a strange Higgs and a top Higgs.
Neutron stars don't have a large radiation pressure. They are inactive stars. Yes, they accelerate stuff from their accredition disc, and thus they send out huge amounts of particles and synchrotron radiation, but only on their poles. But around their equator, they don't have any radiation pressure at all.
And then there is another reason: You want events that send out gravitational waves with a frequency between 100 Hz and 3000 Hz, because that's where LIGO is sensitive. Thus you are confined in the mass of the objects whose gravitational events you can monitor. For other frequencies you either need much larger instruments (e.g. of the length of the Earth's diameter or even larger), or much higher resolutions for the measurements.
Because stars tend not to merge with each other, and thus they don't send out strong gravitational waves. As long as they radiate strongly, they would rather repulse each other than merge.
One of the things that makes that interesting is that when the moon goes overhead, the ground goes up and down by about plus or minus six inches. When this bulge travels past the LIGO sites, the arms of the detectors get stretched. The isolation tables have to compensate for that motion so that the distances between the optics doesn’t change.
If your car is registered in that town, it's your city council you elected which decided to block the roads for certain vehicles. So use your vote next time.
And if not, it's not your taxes there at work.
And you are entitled to use the town roads paid for with your taxes: You can walk on them, ride a bicycle there, stand around, meet people, drive an electric car (your own or someone else's). But you aren't allowed to use an ICE there. You aren't allowed to drive a WW II tank there either. And you aren't allowed to try your new jackhammer on town roads. Or leave your used funiture. Or camp there and burn a fire.
The roads are closed for ICEs (and lots of other things). They are open for you.
It still is an error message. Just because it comes from a different program, it still can be an error message. In this case it is: "Help, my predefined boot image failed. Please give me another one!"
Your first error was to assume that this NAS was just some cheap home appliance.
The host systems I know have large NAS attached to them where all the data resides. Thus for instance, a second host can take over if the first one fails.
Not exactly. Even if you are watching streaming video, this is not necessarily TV broadcasting, as you don't watch your show in sync with all the others watching the same show. Yes, it is passive entertainment with video and sound, but so is watching old VHS, Super-8-movies or a DVD, which you probably won't call "TV" either.
Television means that you watch in realtime some programming that is created at another place (from greek: teleos, far away, and latin: vision, view). And even if the show or movie you are watching was prerecorded, it gets send to all viewers at exactly the same time, so you are still televiewing it, and there is no stop, rewind or anything. If you miss a second, it stays missed, and you can't rewatch it. Netflix, Hulu, Youtube or whatever you call them are totally asynchronous. They are not "far away viewing" something in realtime. You can stop the show and continue at any moment you like.
So stop calling Netflix, Hulu, YouTube, DVDs, pirated movies and shows, etc. TV. Those are the epitomes of Not-TV. All they have in common with TV is that they combine audio- and video signals.
Town roads are not paid for by car taxes or car registration fees. And even if they were: You are also not allowed to drive a car in pedestrian zones, on bike lanes and other ways build with tax money. So the argument "It's paid for by my taxes, so I can drive my car there" doesn't hold.
Whatever arguments you bring up, apparently they are meaningless to enough buyers. I don't need any reason why you won't by a Tesla (I heard you, you never will), but your arguments seem to fall on deaf ears to most people shopping in the luxury car category. Why that might be, I don't know. But the numbers tell us it is that way.
Apparently the general understandment you are citing is not so general at all, or it doesn't influence buyer's opinion that much. Tesla sells more Models S than BMW sells 7 Series, Mercedes-Benz sells S class, or Lincoln sells cars at all. The appeal of a Model S has to be greater than that of other similarly priced cars, quality issues be damned. I don't force you to buy a Tesla yourself. And you won't force me to buy a BMW. To me the appeal of a BMW is close to zero. And I don't own a Tesla either. I use whatever car my company provides. Currently, it's a Skoda (Volkswagen subsidary), in the future, it will probably be a car from Peugeot-Citroen. Neither of them are in any way luxury cars, but they get me from A to B. Your mileage may vary.
Your personal opinion on what a nice car makes doesn't matter very much, except when you personally are shopping for a car. Apparently, enough people are willing to put down money for a Model S, for what reason ever. You might not agree with the people. So what?
I don't agree with people buying a BMW. That doesn't mean that I would call BMW's stock price overvalued, just because their cars don't fit my personal taste. I have to accept that other people want other things in a car than me. And the same is valid for you and your opinion of Tesla's offerings. They don't matter at all for the stock price of TSLA. They are just your personal taste.
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So in a certain way, this picture is everything else but surprising. The biggest surprise is that there were no surprises. The Black Hole at the center of M87 behaves exactly as predicted by General Relativity. The astronomers got exactly what they were searching for.
That's what the observations tell us. We have a disk whose upper side moves away from us. Thus it is not very bright. The lower side moves in our direction, and inbetween we have a space which doesn't emit any light at all.
TL;DR: The star becomes unstable and doesn't live very long.
In the end, we have a pretty good model which puts surface temperature, mass, brightness and lifetime of a star in a single formula. And it tells us, that large stars 10 to 20 times the mass of the Sun will burn through their fusionable material in very short time (1 to 10 million years). Stars even heavier will be unstable, as their emitted energy is not enough to keep the outer shells of the star from falling down into the core, heating it up even more and causing further fusion processes to start, which in turn will cause an explosion of the star. It gets much brighter, pushes its outer shells into space and then cools down, until the remaining star contracts again under its own weight, causing the core to heat up again. Thats why stars of the size of 80 to 200 times the mass of the Sun are called LBVs, Luminous Blue Variables. Because of their heat, they shine in a blue light, and they constantly blow up, reach their peak of brightness, explode, cool down, contract and heat up again.
Stars much larger would be so unstable, that they don't live long enough to be even called stars. They will just collapse under their own weight and turn their core into a neutron star immediately, as the pressure at their core is strong enough to destroy all the electron shells, and push the electrons into the cores, turning protons into neutrons. The energy released will pushing the complete outer regions of the stars into space in a big explosion.
Sorry. 1,000,000 to 5,000,000 times or 1 million to 5 million times brighter. My bad.
The largest stars we know so far have masses of around 200 times the mass of the Sun, e.g. Eta Carinae. Eta Carinae has about 150 to 250 times the mass of the Sun, but it shines between 1,000,000 million to 5,000,000 million times brighter (the brightness actually fluctuates).
Here is a picture of M87 a.k.a. NGC 4486. It's not as if M87 was a totally unknown object before. You can see the large beam ejected from the center of the galaxy. It's about 5000 light years long and is caused by the magnetic field of the rotating Black Hole inside the galactic core of 87. The picture was taken by the Hubble Space Telescope (HST).
From the movement of stars in the center of M87 you can calculate the mass of the center. The movement you can tell from the Doppler effect of their light. If they are moving to us, it is slightly shifted to the blue. If they move away from us, the light is redshifted. That's how you can tell the speed of the stars when circling the galactic center. From the distance to the center, you can tell the orbits. With the orbits and the speed, you know how much mass they are circling, because you can calculate the force that keeps them on their orbits. And when you get a mass of at least 4 billion times the mass of the Sun, you gotta ask which object has so much mass, especially if you don't see the light equivalent of 4 billion stars in the galaxy's center.
And we are talking about radiotelescopes here. What you get is a signal from an antenna, and you have to recalculate the sources of the different waves the antenna recorded. The datapoints are just long lists of energy measurements from the different antennas.
We knew beforehand that M87 (a large eliptical galaxy about 55 million light years away) had a supermassive Black Hole at its center. There were estimates of its size from redshift measurements of the movements of the galaxy's center. Thus this is not a discovery we stumpled upon, this was a carefully selected target, and there were expectations beforehand how the picture should look like. A physicist who wrote his doctorial thesis on how a picture of a Black Hole should look like, gave a speech three month ago (albeit in German): Andreas Mueller: Foto eines Schwarzen Loches.
Even the human eye just uses waves to change the stereochemical properties of some molecule (it turns 11-cis-Retinal into all-trans-Retinal, to be exact, which is the same molecule, but with a different bend in space). Depending on the protein connected to the Retinal (it's called an Opsine), you need different wavelengths for the effect to happen. Then the resulting receptor potential is added up with those of of the neighbouring cells, and about 200 cells send a summary signal via nerve fibers to the brain for further processing.
It would have been very interesting if for instance, the Higgs Boson also comes in generations like the leptons, or if we had something like a strange Higgs and a top Higgs.
Neutron stars don't have a large radiation pressure. They are inactive stars. Yes, they accelerate stuff from their accredition disc, and thus they send out huge amounts of particles and synchrotron radiation, but only on their poles. But around their equator, they don't have any radiation pressure at all.
And then there is another reason: You want events that send out gravitational waves with a frequency between 100 Hz and 3000 Hz, because that's where LIGO is sensitive. Thus you are confined in the mass of the objects whose gravitational events you can monitor. For other frequencies you either need much larger instruments (e.g. of the length of the Earth's diameter or even larger), or much higher resolutions for the measurements.
Because stars tend not to merge with each other, and thus they don't send out strong gravitational waves. As long as they radiate strongly, they would rather repulse each other than merge.
One of the things that makes that interesting is that when the moon goes overhead, the ground goes up and down by about plus or minus six inches. When this bulge travels past the LIGO sites, the arms of the detectors get stretched. The isolation tables have to compensate for that motion so that the distances between the optics doesn’t change.
And if not, it's not your taxes there at work.
And you are entitled to use the town roads paid for with your taxes: You can walk on them, ride a bicycle there, stand around, meet people, drive an electric car (your own or someone else's). But you aren't allowed to use an ICE there. You aren't allowed to drive a WW II tank there either. And you aren't allowed to try your new jackhammer on town roads. Or leave your used funiture. Or camp there and burn a fire.
The roads are closed for ICEs (and lots of other things). They are open for you.
It still is an error message. Just because it comes from a different program, it still can be an error message. In this case it is: "Help, my predefined boot image failed. Please give me another one!"
Last time I checked, this is an error message from Windows Boot Manager, if the predefined boot image fails.
The host systems I know have large NAS attached to them where all the data resides. Thus for instance, a second host can take over if the first one fails.
Television means that you watch in realtime some programming that is created at another place (from greek: teleos, far away, and latin: vision, view). And even if the show or movie you are watching was prerecorded, it gets send to all viewers at exactly the same time, so you are still televiewing it, and there is no stop, rewind or anything. If you miss a second, it stays missed, and you can't rewatch it. Netflix, Hulu, Youtube or whatever you call them are totally asynchronous. They are not "far away viewing" something in realtime. You can stop the show and continue at any moment you like.
So stop calling Netflix, Hulu, YouTube, DVDs, pirated movies and shows, etc. TV. Those are the epitomes of Not-TV. All they have in common with TV is that they combine audio- and video signals.
"But it's Socialism!" is the battle cry coined for them who work for their money by them who have their money work for them.
Town roads are not paid for by car taxes or car registration fees. And even if they were: You are also not allowed to drive a car in pedestrian zones, on bike lanes and other ways build with tax money. So the argument "It's paid for by my taxes, so I can drive my car there" doesn't hold.
Whatever arguments you bring up, apparently they are meaningless to enough buyers. I don't need any reason why you won't by a Tesla (I heard you, you never will), but your arguments seem to fall on deaf ears to most people shopping in the luxury car category. Why that might be, I don't know. But the numbers tell us it is that way.
Apparently the general understandment you are citing is not so general at all, or it doesn't influence buyer's opinion that much. Tesla sells more Models S than BMW sells 7 Series, Mercedes-Benz sells S class, or Lincoln sells cars at all. The appeal of a Model S has to be greater than that of other similarly priced cars, quality issues be damned. I don't force you to buy a Tesla yourself. And you won't force me to buy a BMW. To me the appeal of a BMW is close to zero. And I don't own a Tesla either. I use whatever car my company provides. Currently, it's a Skoda (Volkswagen subsidary), in the future, it will probably be a car from Peugeot-Citroen. Neither of them are in any way luxury cars, but they get me from A to B. Your mileage may vary.
I don't agree with people buying a BMW. That doesn't mean that I would call BMW's stock price overvalued, just because their cars don't fit my personal taste. I have to accept that other people want other things in a car than me. And the same is valid for you and your opinion of Tesla's offerings. They don't matter at all for the stock price of TSLA. They are just your personal taste.