How many stars to expect in Gaia's second data release

April 6, 2018, European Space Agency
Credit: European Space Agency

As astronomers worldwide are preparing to explore the second data release of ESA's Gaia satellite, the Data Processing and Analysing Consortium announced just how many sources will be included in the new catalogue, which will be made public on 25 April.

Launched in December 2013, Gaia is charting more than 1 billion in our Milky Way and neighbouring galaxies, measuring their positions, parallaxes and proper motions at an accuracy level never before achieved, far below one thousandth of an arcsecond.

Parallax is a small motion in the apparent position of a star caused by Earth's yearly revolution around the Sun and depends on the star's distance from us: with measurements of stellar positions and parallaxes, astronomers can pinpoint stars in three-dimensional space. Proper motion is caused by the actual movement of stars through the Galaxy.

Gaia is compiling the largest astrometric catalogue ever created, enabling investigations into the Milky Way's origin and evolution. And there is more: the satellite has also been measuring stellar brightnesses and colours and has been taking spectra of the brightest stars in its survey.

The much awaited second release of Gaia data will contain the position and brightness on the sky of 1 692 919 135 stars, as well as measurements of the parallax and proper of 1 331 909 727 stars.

Derived from 22 months of observations, between 25 July 2014 and 23 May 2016, this represents a huge leap forward with respect to the mission's first data release. The initial release was based on just over one year of data and listed positions of more than one billion stars but 'only' two million parallaxes and proper motions.

The second Gaia data release will also include a wide range of additional information: the colours of 1.38 billion stars; the radial velocities of 7 224 631 stars; information about 550 737 variable sources; an estimate of the surface temperature for 161 497 595 stars, the extinction – a measure of the amount of dust along the line of sight – for 87 733 672 stars, and the radius and luminosity of 76 956 778 stars.

Closer to home, the new data set will contain the position of 14 099 known Solar System objects – mostly asteroids – based on more than 1.5 million observations.

The announcement was made today by Anthony Brown, Chair of the Gaia Data Processing and Analysis Consortium (DPAC) Executive, during the European Week of Astronomy and Space Science in Liverpool, UK.

More details on the content of Gaia's second data release here.

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Benni
1 / 5 (17) Apr 06, 2018
Put an infrared camera on this thing & aim it right at Sgr A*m see if verifies the 7th & 10th photo frames from the top of that web page:

http://ircamera.a...nter.htm
jonesdave
4.8 / 5 (18) Apr 06, 2018
^^^^^^Oh dear, the uneducated loon is back with his 'look at the piccies' unscientific crap. Give up Benni, you're clueless.
Benni
1 / 5 (15) Apr 06, 2018
Put an infrared camera on this thing & aim it right at Sgr A*m see if verifies the 7th & 10th photo frames from the top of that web page:

http://ircamera.a...nter.htm


^^^^^^Oh dear, the uneducated loon is back with his 'look at the piccies' unscientific crap. Give up Benni, you're clueless.


.....and you're opposed to this because it would be just one more nail of OBSERVATIONAL EVIDENCE added to the coffin lid of you're greatest fantasy. Just imagine, two very high resolution pictures proving no black hole exists at Sgr A*, the trauma would be more mind blowing than you could stand.
Spacebaby2001
4.7 / 5 (15) Apr 06, 2018
I don't understand why he keeps using a site explaining how we know there is a black hole at Sgr A* in order to illustrate his point that black holes can't exist. Is he broken? I mean over and over and over again. Is he suffering from anterograde amnesia? And just out of curiosity what in Benni's world is stopping objects from accruing enough mass to have sufficient gravity to not allow light to escape its pull below specific altitude?
jonesdave
4.7 / 5 (12) Apr 06, 2018
.....two very high resolution pictures proving no black hole exists at Sgr A*, the trauma would be more mind blowing than you could stand.


Except that no such pictures exist. Only in your befuddled, scientifically illiterate mind.

jonesdave
4.7 / 5 (13) Apr 06, 2018
Is he broken?


Nah, just thick, with a considerable dash of Dunning-Kruger thrown in.
Benni
1 / 5 (11) Apr 06, 2018
.....two very high resolution pictures proving no black hole exists at Sgr A*, the trauma would be more mind blowing than you could stand.


Except that no such pictures exist. Only in your befuddled, scientifically illiterate mind.
.....here, for your viewing displeasure: http://ircamera.a...nter.htm

See what I mean, already one set of REAL PICTURES have traumatized you, I can just imagine how far over the edge you will go when a 2nd, then a 3rd set of real pics are one day presented showing zero evidence of a 3-4 million SM BH at Sgr A*.

Ok, you guys imagine you're so smart, put up a link that show a 3-4 million SM BH at the center of the Milky Way...........can't do it can you?
jonesdave
5 / 5 (11) Apr 06, 2018
^^^^^^ Idiot doesn't understand the word 'black'! Something else to add to the very long list of things that Benji hasn't got a clue about.
Benni
1 / 5 (10) Apr 06, 2018
I don't understand why he keeps using a site explaining how we know there is a black hole at Sgr A* in order to illustrate his point that black holes can't exist. Is he broken? I mean over and over and over again. Is he suffering from anterograde amnesia? And just out of curiosity what in Benni's world is stopping objects from accruing enough mass to have sufficient gravity to not allow light to escape its pull below specific altitude?


So then explain why you have such an OBSESSION for believing in things you can't see? That's a classic definition of FAITH, sounds nutty to me.

As for me, I believe in things I can see, like the pics at:

http://ircamera.a...nter.htm
jonesdave
4.7 / 5 (13) Apr 06, 2018
So, Benni doesn't believe in electrons. Fine, makes sense. As much sense as any of the other crap that he spouts.
691Boat
4.7 / 5 (13) Apr 06, 2018
I would imagine spectroscopy would be difficult without photons as well. Also, I would be out of a job since my lasers would apparently only be working off of faith, not science.
Benni
1 / 5 (11) Apr 06, 2018
I would imagine spectroscopy would be difficult without photons as well. Also, I would be out of a job since my lasers would apparently only be working off of faith, not science.


........but you can see photons, what is it you think is hitting your eyeballs from your computer screen? Oops, didn't think of that did you? Yeah life is tough living on FAITH alone.
jonesdave
5 / 5 (10) Apr 06, 2018
^^^^^^ Time for your medication, Benni.
691Boat
5 / 5 (11) Apr 06, 2018
I would imagine spectroscopy would be difficult without photons as well. Also, I would be out of a job since my lasers would apparently only be working off of faith, not science.


........but you can see photons, what is it you think is hitting your eyeballs from your computer screen? Oops, didn't think of that did you? Yeah life is tough living on FAITH alone.

Oh, neat! You have pictures of a photon?
jonesdave
5 / 5 (11) Apr 06, 2018
Oh, neat! You have pictures of a photon?


Yeehaw! We need to know whether it was a wave or a particle! Benni, don't keep it to yourself, the world needs to know.

Benni
1 / 5 (11) Apr 06, 2018
Oh, neat! You have pictures of a photon?


Yeehaw! We need to know whether it was a wave or a particle! Benni, don't keep it to yourself, the world needs to know.


Then the two of you must be blind if you can't see electro-magnetic waves........but that makes perfect sense, classic case of the blind leading the blind.
jonesdave
4.6 / 5 (10) Apr 06, 2018
^^^^^^You can't see a photon, you prawn. Your retina is a detector, just like 35mm film, or a digital camera sensor. Your brain (???) creates the image you see.
https://www.lives...rks.html
Da Schneib
4.6 / 5 (10) Apr 07, 2018
Meh, technically after developing your scotopic vision for a half hour or so, you can see the sparkle of two photons striking at the right distance apart. If you want to call one minute sparkle that lasts only a moment "seeing."
ShotmanMaslo
4.6 / 5 (10) Apr 07, 2018
Sagittarius A black hole should have a diameter of around 44 million kilometers. It is too small to be visible. Maybe in near future radio interferometers will be able to resolve the event horizon.
Benni
1 / 5 (12) Apr 07, 2018
Sagittarius A black hole should have a diameter of around 44 million kilometers. It is too small to be visible. Maybe in near future radio interferometers will be able to resolve the event horizon.


The experts who took the pictures of the center of the galaxy say you are dead wrong when making such an ignorant statement, here go look at what they had to say:

"Here is a very deep, high resolution (1 arcsec) xray image of the Galactic Center -- the source elongated up and down just above and to the right of the center is Sgr A*, but it doesn't stand out at all. Even in X-rays, where we look to find stellar black holes, there is nothing to draw our attention to the supermassive black hole here!" (caption next to the 10th photo frame from the top of the page)

So tell us, why do you imagine you know more than the experts?

http://ircamera.a...nter.htm

jonesdave
4.6 / 5 (11) Apr 07, 2018
So tell us, why do you imagine you know more than the experts?


He isn't saying that. The problem is that you are lying about what the experts are saying, as usual. Why don't you click the link in the credit for that X-ray image? It takes you to:
http://chandra.ha...dex.html where there is a longer description of what the image is, including:

The cause of these outbursts is not understood, but the rapidity with which they rise and fall indicates that they are occurring near the event horizon, or point of no return, around the black hole.


You could then check out the reference for the image, which is F. K. Baganoff, et al. Given that the image is from 2003, then I'm assuming the paper is:

CHANDRA X-RAY SPECTROSCOPIC IMAGING OF SGR A∗ AND THE CENTRAL PARSEC OF THE GALAXY
https://arxiv.org...2151.pdf

Again, this has nothing to say about the non-existence of a BH. Quite the opposite. So quit lying.
jonesdave
4.5 / 5 (8) Apr 07, 2018
Sagittarius A black hole should have a diameter of around 44 million kilometers. It is too small to be visible. Maybe in near future radio interferometers will be able to resolve the event horizon.


Actually Shotman, using the equation for the Schwarzschild radius gives ~ 12m km, so a diameter of ~ 24m km. Strangely, you used the same figure Benni came up with, without any working being shown as to how he arrived at the figure. I'd be interested where you got the figure from. I'm guessing that you found it on a forum by Googling. This would back up our beliefs here that Benni is actually incapable of doing the necessary simple maths equation himself, despite his claims to be capable of doing diff. eqs., and had to do a search, and managed to come up with the wrong answer!
Benni
1 / 5 (9) Apr 07, 2018
The problem is that you are lying about what the experts are saying,


That telescope & camera at http://ircamera.a...nter.htm has driven you, RNP, Schneibo, etc, into absolute apoplexy after you bunch of foul mouthed name calling neophytes were adamant that the resolution of the pictures found at this website could not exist.

I let the bunch of you post you silly tripe about resolution of IMAGES at the center of the galaxy & you ended up with your feet in your mouths because you old men had forgotten we are no longer living in & using 20th century technology to image the Universe, yeah, it's the 21st century, get used to it.
torbjorn_b_g_larsson
4.6 / 5 (11) Apr 07, 2018
I don't understand why he keeps using a site explaining how we know there is a black hole at Sgr A* in order to illustrate his point that black holes can't exist. Is he broken?


If we read his comments as is, yes. He also does not seem to know that a satellite is a spacecraft, and that Gaia is orbiting L2 out beyond the Moon distance. And he claims that photons are visible, but even our mostly-not-photon-detecting eyes pick up a very small slice of all photon wavelengths.

Is the idea that black holes do not exists, despite the many generic observation of colliding holes and the many more special ones, such as the ways the SagA* SMBH is observed? Then that adds to the crackpot index sum as well.
Benni
1 / 5 (7) Apr 07, 2018
such as the ways the SagA* SMBH is observed
.....ok, go to the pictures at the website & show us where there is this OBSERVATIONAL EVIDENCE you claim exists there? Can't do it can you?

So you, answer the question posed at the website next to the 10th photo frame::

"Here is a very deep, high resolution (1 arcsec) xray image of the Galactic Center -- the source elongated up and down just above and to the right of the center is Sgr A*, but it doesn't stand out at all. Even in X-rays, where we look to find stellar black holes, there is nothing to draw our attention to the supermassive black hole here!"

........don't like that picture or the caption next to it do you.

This is what happens when so many of you claimed there existed no technology that could resolve images of individual stars at the galactic core, you ended up with your feet in your mouths because you're so stuck in 20th century technology that you had forgotten we are almost two decades beyond that.
jonesdave
4.6 / 5 (9) Apr 07, 2018
........don't like that picture or the caption next to it.


Oh dear, more scientifically illiterate idiocy from Dunning-Krugerland. I linked to the original source, and the paper. You want to play with crayons on your monitor. Go away Benni, you're pointless.
Benni
1 / 5 (8) Apr 07, 2018
........don't like that picture or the caption next to it.


Oh dear, more scientifically illiterate idiocy from Dunning-Krugerland. I linked to the original source, and the paper. You want to play with crayons on your monitor. Go away Benni, you're pointless.


.......coming from one of the neophytes who claimed that images of individual stars at the galactic core did not exist because we did not have telescopic technology with the resolution capability of taking pictures of individual stars, and to make a liar out of him, Schneibo, & RNP I produced :

http://ircamera.a...nter.htm

.......and they haven't recovered since.

Hey guys, when the REAL DEAL is slapping you up alongside the head, you're better off just dealing with your mistakes rather than go on another one of your unending name calling rants.
jonesdave
4.6 / 5 (9) Apr 07, 2018
.....coming from one of the neophytes who claimed that images of individual stars at the galactic core did not exist....


More lies. I have been well aware of the animations and images on the UCLA galactic centre webpage for years. That's how we know there is a 4m Msun object there, you idiot. You told us nothing, other than that you are scientifically illiterate. But we already knew that. Get back to your mopping, and put the crayons down.

Benni
1 / 5 (9) Apr 07, 2018
More lies. I have been well aware of the animations and images on the UCLA galactic centre webpage for years. That's how we know there is a 4m Msun object there


OK, then tell us where in the real stellar images (not animations) we can see the image of "a 4m Msun object". http://ircamera.a...nter.htm

Photo images 7th & 10th from the top of the page would be the pictures where the most massive object in the galaxy would be so obvious that even your poor eyesight could gather in enough electro-magnetic waves to discern the image. See it?

See the caption right next to the 10th photo? What does it say? It says: "there is nothing to draw our attention to the supermassive black hole here!"...........no observational evidence.
jonesdave
4.5 / 5 (8) Apr 07, 2018
OK, then tell us where in the real stellar images (not animations) we can see the image of "a 4m Msun object".


Jesus, what an idiot! Those animations cover something like 16 years of observations! They do not have a frigging movie camera pointed at the galactic centre that they leave running for decades! They take telescopic images every so often. Then you can create an animation with the images. Like taking a picture of a tree in the local park, once a month for 16 years, and turning those images into a .gif file.
I swear we are dealing with a 10 year old here!

there is nothing to draw our attention to the supermassive black hole here!"


No, there ****ing wouldn't be you chump! That is the point the site is making. Remember the words quiescent? And non-thermal? When it does do something that is able to be seen in x-ray, it is seen. This is not a continuous process as it may be around more active SMBHs. How hard can this be to understand?
Benni
1 / 5 (9) Apr 07, 2018
The instruments we currently possess do not have the resolution to give an accurate size of it.
VLBI will allow us to (hopefully) see the event horizon. Of course, if it isn't a BH we won't see it


Read more at: https://phys.org/...html#jCp

More lies. I have been well aware of the animations and images on the UCLA galactic centre webpage for years. That's how we know there is a 4m Msun object there


Known it "for years" ? Jonesy, you only learned about such imaging technology on Feb 18, 2018, the date of the link in which you clearly stated imaging technology resolving individual stellar mass at the center of the galaxy does not exist. So, who's the liar?

Jonesy, your biggest failure in life is simply that of being honest with yourself, and when you can't even do that it's no wonder you come to a place like this & make a dismal fool of yourself on such a frequent basis.
jonesdave
4.6 / 5 (9) Apr 07, 2018
^^^^^^Again, you're talking out of your arse, and simply do not understand the subject under discussion. The stars have a THERMAL signature, you oaf. That is how they can be seen in IR. The BH DOES NOT. Understand? Bloody unlikely. They have been mapping the orbits of these stars for decades. That is how they know there is a 4m Msun BH there, you dolt. It has been in the scientific literature, for anybody interested, for decades. Why are you only learning about it now? Probably weren't born when they started. Well, now that you're about to finish grade school, here is a conference paper on observations from 1995-1997:
http://articles.a...ype=.pdf
jonesdave
4.6 / 5 (10) Apr 07, 2018
Hey, imbecile Benji, here's another paper from 2000, where they explain how they plot the movement and acceleration of the stars:
https://arxiv.org...9339.pdf

Guess what? It doesn't involve the use of crayon and a computer monitor! Loon.
Benni
1 / 5 (9) Apr 07, 2018
simply do not understand the subject under discussion. The stars have a THERMAL signature, you oaf. That is how they can be seen in IR. The BH DOES NOT. Understand? Bloody unlikely. They have been mapping the orbits of these stars for decades. That is how they know there is a 4m Msun BH there, you dolt. It has been in the scientific literature, for anybody interested, for decades. Why are you only learning about it now? Probably weren't born when they started. Well, now that you're about to finish grade school, here is a conference paper on observations from 1995-1997:
http://articles.a...ype=.pdf


.....but you didn't know anything about any such imaging till I pointed it out to you on Feb 18, 2018. Now look how fast you did a turnaround, a turnaround so fast it could be better labeled as a spin, yeah, "spin", something you spend a lot of time doing here.
jonesdave
4.4 / 5 (7) Apr 07, 2018
^^^^^WTF are you on about D-K boy? YOU had to tell us about IR and x-ray imaging of the galactic centre? Hahahahahahahahahaha. What a prat. I was studying this sort of thing when your unfortunate mother was still wiping your arse. Probably still is. Go away you tiresome troll. Learn some science.
ShotmanMaslo
4.5 / 5 (8) Apr 07, 2018
"Here is a very deep, high resolution (1 arcsec) xray image of the Galactic Center -- the source elongated up and down just above and to the right of the center is Sgr A*, but it doesn't stand out at all. Even in X-rays, where we look to find stellar black holes, there is nothing to draw our attention to the supermassive black hole here!"


Benni, that precious image of yours is 8.4 arc minutes on a side. It is around 64 light years wide, assuming my math is correct. You are not going to resolve a mere 24 million kilometer wide black hole in such picture. At best it will only be a single bright pixel at center of the image, a point x-ray source. There is no imaging technology yet to see the black hole, it is too small. Maybe radio interferometers will be able to see the hole itself in the future, but not yet.
ShotmanMaslo
4.5 / 5 (8) Apr 07, 2018
Actually Shotman, using the equation for the Schwarzschild radius gives ~ 12m km, so a diameter of ~ 24m km. Strangely, you used the same figure Benni came up with, without any working being shown as to how he arrived at the figure. I'd be interested where you got the figure from. I'm guessing that you found it on a forum by Googling.


You are of course correct. I quickly googled it up, but it seems ~24m km is the correct size.
jonesdave
4.4 / 5 (7) Apr 07, 2018
There is no imaging technology yet to see the black hole, it is too small. Maybe radio interferometers will be able to see the hole itself in the future, but not yet.


Not yet, but soon! With any luck, the Event Horizon Telescope should be announcing their results this year:
https://eventhori...-15-2017

Benni
1 / 5 (9) Apr 07, 2018
Benni, that precious image of yours is 8.4 arc minutes on a side. It is around 64 light years wide, assuming my math is correct.
Your math isn't correct:

"Here is a very deep, high resolution (1 arcsec) xray image of the Galactic Center -- the source elongated up and down just above and to the right of the center is Sgr A*, but it doesn't stand out at all. Even in X-rays, where we look to find stellar black holes, there is nothing to draw our attention to the supermassive black hole here"

http://ircamera.a...nter.htm

Shot your wad on that one: 11th photo from the top of the page is 1 arcsec.

By the way Shotyourwad, it isn't MY image: (from NASA/CXC/MIT/F.K.Baganoff et al. http://chandra.ha...dex.html

Now, do you think you have enough proficiency in math to compare 1 arcsec to the erroneous claim you made of 8,4 arcminutes?
jonesdave
4.5 / 5 (8) Apr 07, 2018
Now, do you think you have enough proficiency in math to compare 1 arcsec to the erroneous claim you made of 8,4 arcminutes?


Ladies and gentleman, behold the buffoonery of the average crank!
Now, listen very carefully, because I shall say this only once; the resolution of the telescope that took the image, is 1 as. That means it can't see anything less than 1 as in size. This SIZE of the entire image is 8.4 arcminutes on a side. There is a clue to this on the Chandra page, in the image data at the end of the article, where it says:

Scale...........................Image is 8.4 arcmin on a side


No maths required for that. Just comprehension skills.

jonesdave
4.4 / 5 (7) Apr 07, 2018
Your math isn't correct:


Yes, ShotmanMaslo's maths is atrocious. I make it 63.54 ly :)

Ok, short version. Distance to centre of galaxy = 26 000 ly. Therefore radius x 2 = 52 000 ly diameter. Circumference = Pi x diameter = 163363 ly.
There are 21 600 arcmins in 360 degs. So, 21 600/ 8.4 = 1/2571 of the circumference.
163363/ 2571 = 63.54 ly. Simples. Unless you're Benni.
jonesdave
4.4 / 5 (7) Apr 07, 2018
So, another way of looking at that image, is that it is 8.4 x 60 arcsecs across = 504 as. As the resolution of the 'scope is 1 as, then it can resolve 63.54 ly/ 504 = 0.126 ly. = ~ 1 x 10^12 km. = ~ 6700 AU.
Schwarzschild radius = ~ 12 x 10^6 km. Diameter of BH therefore = ~ 24 x 10^6 km. So, about 40 000 times smaller than the 'scope's resolution.
Good, glad we got that sorted out.
Benni
1 / 5 (9) Apr 07, 2018
Good, glad we got that sorted out.


Nope all you did was muddle through a bunch of numbers about telescopic resolution which is just more of your irrelevant spin,it's the actual pics that tell the story & those are real.

On the website: http://ircamera.a...nter.htm

"Ever increasing resolution showed the black hole is not the energy source. The brightest source in the very high resolution near infrared image to the right is IRS 7, a red supergiant that puts out most of its energy in the near infrared. The other bright stars are also very young and massive. The blue-appearing ones in the center of the image are a unique clustering of very luminous, massive stars." ..........8th photo/caption frame from the top of the page.

Drawing attention to IRS 7 which is about the size of what the BH would be. The BH would be located just below IRS 7, & be easily visible in this pic at that size if it existed, it isn't there.
jonesdave
4.5 / 5 (8) Apr 07, 2018
Nope all you did was muddle through a bunch of numbers about telescopic resolution which is just more of your irrelevant spin..


Nope, not spin. Simple maths, the kind which you are incapable of, bozo.
And IRS-7 is a star (Google it). Stars are hot. Lots of thermal radiation. You can see that stuff in IR. The BH is is mostly non-thermal. It is therefore very difficult to see in IR, except when it has the occasional snack. When it is seen in IR. Stars, however, are permanently hot. Try to get your befuddled mind around this; it has been explained enough times that even a 10 year old would have figured it out by now.

jonesdave
5 / 5 (8) Apr 07, 2018
Drawing attention to IRS 7 which is about the size of what the BH would be...


Really? What is the size of the BH? Never mind, you messed that up last time! It has a diameter of ~ 24m km. That is ~ 1/6th of an AU. If it was centred on the Sun. the EH would be less than halfway to Mercury.
So, let's look at another M1-M2 red supergiant - Betelgeuse. Now if it were in the solar system, its 'surface' would be beyond the orbit of the asteroid belt. Big difference. And it's very luminous. And the BH isn't.
Are we getting it yet? Nope, didn't think so.
SkyLight
5 / 5 (9) Apr 08, 2018
@Benni
Then the two of you must be blind if you can't see electro-magnetic waves
So, you're saying we should be able to "see" radio waves, microwaves, infrared and ultraviolet, x-rays and gamma rays?

Or is that another super-power you possess, in addition to seeing stuff in images which isn't there?
Benni
1 / 5 (8) Apr 08, 2018
What is the size of the BH? Never mind, you messed that up last time! It has a diameter of ~ 24m km. That is ~ 1/6th of an AU. If it was centred on the Sun. the EH would be less than halfway to Mercury.


Jonesy, you need to learn to depend on sources more reliable & knowledgeable than yourself:

"Diameter estimates for one at the center of the Milky Way have ranged widely, from as small as the orbit of Mercury to as big as that of Pluto."

"Last year, researchers estimated it was as wide as Earth's orbit around the Sun. The new estimate reduces that measurement by half, indicating the diameter of Sgr A*, as the object is known, is about 93 million miles -- same as the distance between Earth and the Sun." https://www.space...zed.html

Benni
1 / 5 (8) Apr 08, 2018
Or is that another super-power you possess, in addition to seeing stuff in images which isn't there?


You're one of the ones here who claims there's a BH at Sgr A*, but in the clearly resolved IMAGES at http://ircamera.a...nter.htm at the 8th photo frame from the top of the page show no electro-magnetic wave of evidence for it at any WAVELENGTH of electro-magnetic waves. Capiche? Probably not.
jonesdave
4.2 / 5 (5) Apr 08, 2018
Jonesy, you need to learn to depend on sources more reliable & knowledgeable than yourself:

"Diameter estimates for one at the center of the Milky Way have ranged widely, from as small as the orbit of Mercury to as big as that of Pluto."

"Last year, researchers estimated it was as wide as Earth's orbit around the Sun. The new estimate reduces that measurement by half, indicating the diameter of Sgr A*, as the object is known, is about 93 million miles -- same as the distance between Earth and the Sun." https://www.space...zed.html


Well, you go dig up the papers that that 2005 article refers to, and in the meantime I'll go with:

Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre
Doeleman, S. S. et al.
https://arxiv.org...2442.pdf

At a distance of ∼8kpc (ref. 8), the Sgr A* Schwarzschild radius is 10μas, or 0.1 astronomical unit (AU).
jonesdave
4.3 / 5 (6) Apr 08, 2018

You're one of the ones here who claims there's a BH at Sgr A*, but in the clearly resolved IMAGES at http://ircamera.a...nter.htm at the 8th photo frame from the top of the page show no electro-magnetic wave of evidence for it at any WAVELENGTH of electro-magnetic waves. Capiche? Probably not.


Lol. What an idiot. "Look at the picture of the non-bunnies. That proves that bunnies don't exist." How much stupid does it take for some loon to do science like that? A grade school level of understanding, is what that is.
Here, Benji, to save you the embarrassment of screwing up the maths again, I've found a Sch. radius calculator for you, dear:
https://www.eso.o...kout.htm

Now all you have to do is put 4 million (that's a 4 followed by 6 zeros) into the box labelled 'Number of Sun Mass' and press 'calculate'. Even you couldn't f*** that up.
SkyLight
4.6 / 5 (11) Apr 08, 2018
Your "clearly resolved images", as the others here repeatedly tried to point out to you, are of a region a few parsecs across surrounding the GC. The SMBH's event horizon is so small on that scale, it's VERY much smaller than the individual pixels in the images. And the BH itself doesn't radiate in IR or UV, unlike the stars around it.

Think about that for a minute - trying to catch sight of the SMBH in those images is like trying to find a small black object lying on a traffic-busy blacktop road at night in downtown Dallas, from a hand-sized image of the state of Texas.

The others here, whom you so roundly condemn as idiots, understand this simple fact. Continuous OBSERVATIONS of your actions and words clearly show the FACT of your scientific ignorance, a fact which you are unable or unwilling to comprehend.

You successfully hoist yourself by your own petard every time you commit finger to keyboard, or crayon to monitor. Capiche?
SkyLight
4.6 / 5 (11) Apr 08, 2018
Actually, the small black object in the road is not a bad analogy for what's happening at the GC, even if i do say so myself.

So, imagine it's night-time, and that the small object on the blacktop is visible to the vehicle drivers when they get close enough to it, and that they all swerve to avoid colliding with it. Now imagine yourself in an airplane flying high over that road. You can't make out any details of the road surface, or of the object, but you can see the headlights of the vehicles swerving to avoid something. You can't see the object, but you see the vehicle lights are affected by it to the extent that they avoid it.

In a similar way, the stars very close to the GC are also seen to follow paths which are affected by something nearby. In this case, the paths trace out orbits of the stars around something very massive, and very close, but which can't (yet) be seen.

And that's the SMBH. Or maybe the swollen super-degenerate brain of a Nuclear Electrical Engineer?
jonesdave
4.5 / 5 (8) Apr 08, 2018
I said:

Well, you go dig up the papers that that 2005 article refers to, and in the meantime I'll go with:....


Don't fret Benni, I found it:

A size of ∼ 1 AU for the radio source Sgr A⋆ at the centre of the Milky Way
Zhi-Qiang Shen, et al.
https://arxiv.org...2515.pdf

This is just the reporting (in 2005!) of the best maximum size determination available at that time, in radio wavelengths. They also say:

Thus we have sampled a zone of the SMBH closer to the event horizon than ever before, by detecting the intrinsic size of Sgr A* to be only 1.01 AU at a distance of 8.0 kpc, or 12.6Rsc, where Rsc (= 1.2 x 10^12 cm) is the Schwarzschild radius of a 4u10^6 Msun SMBH.


Now, what distance is 1.2 x 10^12 cm in km? What is it in AU? I'll leave that to the mathematically able readers to explain it to Benni.

SkyLight
4.3 / 5 (6) Apr 08, 2018
in the clearly resolved IMAGES [] at the 8th photo frame from the top of the page show no electro-magnetic wave of evidence for it at any WAVELENGTH of electro-magnetic waves
OK, so ... ANY wavelength of EM waves?

(Q) How many images in the page you link to were taken in UV light? or at sub-millimeter wavelengths? or gamma rays? or at 6-meter VHF, or at the 13CS (2-1) emission line?

(A) none of 'em.

The images in the page you link to were taken at only a few EM ranges: X-rays, optical, IR, far IR, centimeter radio. So, hardly the full spectrum, Benni.
Benni
1 / 5 (8) Apr 08, 2018
Your "clearly resolved images", as the others here repeatedly tried to point out to you, are of a region a few parsecs across surrounding the GC


The 8th photo/anmation frame from the top is just bedeviling the hell outta you guys isn't it:

"Ever increasing resolution showed the black hole is not the energy source. The brightest source in the very high resolution near infrared image to the right is IRS 7, a red supergiant that puts out most of its energy in the near infrared. The other bright stars are also very young and massive. The blue-appearing ones in the center of the image are a unique clustering of very luminous, massive stars."

All those high resolution images of stars surrounding Sgr A* packed so close together the distances between many of them would be measured in lightdays. But somehow, an image that would rival IRS 7 in size is just waaaaayyyyyyyyy too small for the employed optics to resolve imaging a 3-4 million SM bh.
jimmybobber
4.6 / 5 (11) Apr 08, 2018
Benni. I do not understand you.
The evidence based on the motion of the S2 star points to the existence of a black hole in the center of the Milky way.
I going to guess you don't believe in black holes.
jimmybobber
4.6 / 5 (11) Apr 08, 2018
Benni. I also read your link http://ircamera.a...ter.htm.
The link concludes that there is a black hole there.
Benni
1 / 5 (8) Apr 08, 2018
Benni. I do not understand you.
.......it shouldn't be hard, below is a link to Einstein's FALSIFICATION of Schwarzschild's black hole math with his concluding comments. This along with zero OBSERVATIONAL EVIDENCE at Sgr A*.

Albert Einstein- Oct 1939

On a Stationary System With Spherical Symmetry Consisting of Many Gravitating Masses

Author(s): Albert Einstein Reviewed work(s): Source: The Annals of Mathematics, Second Series, Vol. 40, No. 4 (Oct., 1939), pp. 922-936 Published by: Annals of Mathematics Stable URL:.
http://www.cscamm...hild.pdf

"The essential result of this investigation is a clear understanding as to why the "Schwarzschild singularities" do not exist in physical reality. The "Schwarzschild singularity" does not appear for the reason that matter cannot be concentrated arbitrarily. And this is due to the fact that otherwise the constituting particles would reach the velocity of light."
jimmybobber
4.4 / 5 (7) Apr 08, 2018
Just because the mathematics inside a black hole isn't understood doesn't mean there isn't still a massive object there with an immense gravitational field that light can't escape. Think of it as a star massive and dense enough that it has an event horizon where light cannot escape from.

Your issue seems to be with the fact that General Relativity and Quantum Mechanics are still incomplete and don't play well together.
jonesdave
4.3 / 5 (6) Apr 08, 2018
Just because the mathematics inside a black hole isn't understood doesn't mean there isn't still a massive object there with an immense gravitational field that light can't escape. Think of it as a star massive and dense enough that it has an event horizon where light cannot escape from.

Your issue seems to be with the fact that General Relativity and Quantum Mechanics are still incomplete and don't play well together.


Mate, don't even bother. The bloke is as thick a pigshit. End of story. He/She really does not have a clue about some very straight forward science. Best to just ignore the jerk.
Benni
1 / 5 (6) Apr 08, 2018
Mate, don't even bother. The bloke is as thick a pigshit. End of story. He/She really does not have a clue about some very straight forward science. Best to just ignore the jerk
..........coming from the guy who can't remember if it was in high school algebra class that he took Differential Equations or during that one year stint he spent at Uni in Auckland.

Hey, how come only one year at Uni? A major in "Name Calling Tirades" couldn't have been all that daunting.

Benni
1 / 5 (8) Apr 08, 2018
Just because the mathematics inside a black hole isn't understood
......what math are you alluding to?
Maybe you can be the first to explain how a finite stellar mass can have an inherent feature of infinite gravity at it's surface, or center, etc? You are aware that according to Einstein's General Relativity that GRAVITY is MASS DEPENDENT, right?

doesn't mean there isn't still a massive object there with an immense gravitational field that light can't escape.
....where's your math for that? Or better yet, OBSERVATIONAL EVIDENCE?

Your issue seems to be with the fact that General Relativity and Quantum Mechanics are still incomplete and don't play well together.
No, my issue is that it can't be proven that infinite gravity can exist at the surface of a finite stellar body, a body for which there is no OBSERVATIONAL EVIDENCE to prove there exists a body with a gravitational field so strong it can reduce an EM Wave to zero velocity.
jimmybobber
4.5 / 5 (8) Apr 08, 2018
The mathematics of General Relativity and Quantum Mechanics.
Where do you get the idea there is infinite gravity? If the mass is finite why would the gravity be infinite?

The observational evidence was in the link you yourself posted. They can reason the mass exists because of the motions of the stars around it.

EM waves are not reduced to zero velocity. The space-time is bent such that the EM waves do not have a path extending outside of the even horizon once they pass it.
jimmybobber
5 / 5 (7) Apr 08, 2018
Bennit.
This reminds me of Coulomb's Law for the force between two charges.

It's a 1/r^2 law. If r goes to zero then the force is undefined (some may say the force goes to infinity which is incorrect.) Anyhow the distance say between a proton and electron will never go to zero. Quantum Mechanics saves the day. The electron can only exist at discrete energy states around the proton and there is a minimum energy state.

It seems like your hung up on a similar analogy regarding black holes.
Benni
1 / 5 (8) Apr 08, 2018
Where do you get the idea there is infinite gravity? If the mass is finite why would the gravity be infinite?


https://en.wikipe...ack_hole

Singularity

Main article: Gravitational singularity

"At the center of a black hole, as described by general relativity, lies a gravitational singularity, a region where the spacetime curvature (gravity) becomes infinite. For a non-rotating black hole, this region takes the shape of a single point and for a rotating black hole, it is smeared out to form a ring singularity that lies in the plane of rotation.In both cases, the singular region has zero volume. It can also be shown that the singular region contains all the mass of the black hole solution. The singular region can thus be thought of as having infinite density."

So, tell us who is right, you or the classic definition of Black Hole as I just quoted from WikiPedia?
SkyLight
4.6 / 5 (9) Apr 08, 2018
So, tell us who is right, you or the classic definition of Black Hole as I just quoted from WikiPedia?
Benni, The Wiki article you quote from is a nice introduction to BH's in layman's terms, with a few simple equations thrown in for good measure; it cannot be taken as "the classic definition" of a BH. Only the math of GR, supported by a whole lot of other math (Schwarzschild and Kerr solutions, etc.) can be taken as "the classic definition", since the math is the primary source.

Oh, and if you're going to quote a source like the Wiki article, you don't flagrantly insert your own words - like your "(gravity)" - to make it read the way you want it to. The article very clearly stays away from stating - as you so evidently wish it did - that gravity becomes infinite at the singularity.

As @jb stated correctly above, the mass of the BH is not infinite, so the gravity cannot "become" infinite anywhere. Only the ***curvature of spacetime*** becomes infinite at the singularity.
yep
1.5 / 5 (8) Apr 09, 2018
"Curvature of Space Time" meaningless dribble and mathematical fantasy having no basis in reality like dark energy and black holes. You are all so smart you're stupid, but keep that grant money rolling in, daddy needs a new ride!
SkyLight
4.6 / 5 (9) Apr 09, 2018
You are all so smart you're stupid, but keep that grant money rolling in, daddy needs a new ride!
You're so stupid that in the last nine years of trolling this site, you've learned precisely nothing. Or to put it another way: you're so stupid you're stoopid.

And all the grant moneys allotted to math, physics, astrophysics studies in the world are but a couple of drops in the ocean compared to the gigantic "salaries" and bonuses which CEO's are paying themselves these days, or the truly astronomical amounts shelled out (pun intended) to the military.industrial complex. Those daddies are getting executive jets to ride in!

But, hey, don't let a few facts stop you from swallowing the latest conspiracy theories: anything to raise your head above the surface of the murky, turd-infested pool you inhabit.
Benni
1 / 5 (9) Apr 09, 2018
But, hey, don't let a few facts stop you from swallowing the latest conspiracy theories: anything to raise your head above the surface of the murky, turd-infested pool you inhabit


Right, like the high resolution pics at http://ircamera.a...nter.htm at the 8th photo/animation frame from the top of the page stating this:

"Ever increasing resolution showed the black hole is not the energy source. The brightest source in the very high resolution near infrared image to the right is IRS 7, a red supergiant that puts out most of its energy in the near infrared."

or at the 11th stating this:

"Here is a very deep, high resolution (1 arcsec) xray image of the Galactic Center -- the source elongated up and down just above and to the right of the center is Sgr A*, but it doesn't stand out at all. Even in X-rays, where we look to find stellar black holes, there is nothing to draw our attention to the supermassive black hole here."

Benni
1 / 5 (10) Apr 09, 2018
if you're going to quote a source like the Wiki article, you don't flagrantly insert your own words - like your "(gravity)"


spacetime curvature - Obviously you know so little about ANYTHING in General Relativity that you don't know SPACETIME CURVATURE. Here, just to make it simpler for you:

"Local Curvature of Space. According to Einstein's theory of general relativity, massive objects warp the spacetime around them, and the effect a warp has on objects is what we call gravity. So, locally, spacetime is curved around every object with mass."

http://www.skyand...spacece/

But, hey, don't let a few facts stop you from swallowing the latest conspiracy theories.
SkyLight
5 / 5 (8) Apr 09, 2018
@Benni, read the article - "Ever increasing resolution showed the black hole is not the energy source" refers in that instance to the energy source of UV or of radio emissions, and where the BH itself (or, more accurately, the region just outside the SR) is not the primary source.

Similarly, the quote "Even in X-rays, where we look to find stellar black holes, there is nothing to draw our attention to the supermassive black hole here." refers to the lack of X-ray emissions from the same region. And "there is no significant source in the near infrared associated with the black hole (although brief flares have been detected)" refers to the lack of IR emissions from that same region of space.

So, given the orbital dynamics of the stellar population in the vicinity of what is undoubtedly a very massive object, and given that no EM radiation is emitted by that object, the authors admit to being puzzled. Situation normal: that's how science progresses...
SkyLight
5 / 5 (9) Apr 09, 2018
So, Benni, a few words from a popular astronomy website cuts more ice for you than the rigorous math of GR. No surprises there...

Here's a very nice paper by Dafermos, where the first sentence of the paper's abstract reads
The mathematical analysis of black holes in general relativity has been the focus of considerable activity in the past decade from the perspective of the theory of partial differential equations
Should be right up your street, Benni, given your expertise in PDE's and all.
jonesdave
5 / 5 (6) Apr 09, 2018
Should be right up your street, Benni, given your expertise in PDE's and all.


You forgot the sarcasm tags!
Spacebaby2001
5 / 5 (8) Apr 09, 2018
So then explain why you have such an OBSESSION for believing in things you can't see? That's a classic definition of FAITH, sounds nutty to me.

As for me, I believe in things I can see...


I couldn't care less whether there's a bh at Sgr A* or its just a big ball of your insanity. The characteristics scientists deduce of Sgr A* have no impact on my life.

If you had any kind of reasonable explanation for the motions of the stars orbiting Sgr A*, or an explanation for what happens to matter as it coalesces into the densities that others are saying create a bh, then maybe you wouldn't come off as such a loon.

Instead you post the same link that explains how scientists deduced the smbh with observational evidence, the very object your claiming doesn't exist, exclaiming how there's no observational evidence.

On the bright side I'm learning a lot from the people trying to educate you.
jimmybobber
5 / 5 (8) Apr 09, 2018
Benni if you only investigate further.
This is a wonderful wikipedia entry. Please read it all.
https://en.wikipe...gularity

"Many theories in physics have mathematical singularities of one kind or another. Equations for these physical theories predict that the ball of mass of some quantity becomes infinite or increases without limit. This is generally a sign for a missing piece in the theory, as in the Ultraviolet Catastrophe, re-normalization, and instability of a hydrogen atom predicted by the Larmor."

jimmybobber
5 / 5 (7) Apr 09, 2018
Another well written article:
http://www.pbs.or...es-real/

Snippet:

"Are these singularities real, or just vestiges of the gap between math and reality? Based on their experience with other systems, physicists suspect that the singularities in General Relativity are a warning, a tip-off that we need another theory to describe the physics in the extreme situations when gravity is very strong and its quantum effects are very large. Physicists still don't know how to describe the quantum effects of gravity, but we hope that by doing so we will one day resolve the singularities."
SkyLight
5 / 5 (5) Apr 09, 2018
You forgot the sarcasm tags!
Hot dang, @jd - you're right! How's Benni going to know I was being sarcastic, unless I put up a big sign saying so?
SkyLight
5 / 5 (7) Apr 09, 2018
@jimmyb - nice comments! Just don't expect Benni to follow any helpful hints or links or suggestions, 'coz he won't/can't - he lives in his own closed-off region of space behind the event-horizon of his own tantrum-field, the strength of which appears to be proportional to the square of the distance to his comfort blanket.
SkyLight
5 / 5 (8) Apr 09, 2018
nstead you post the same link that explains how scientists deduced the smbh with observational evidence, the very object your claiming doesn't exist, exclaiming how there's no observational evidence.
Precisely! - the lights are on at Chez Benni, but nobody's home...
yep
1 / 5 (5) Apr 09, 2018
Well I'm in agreement with you over the military industrial complex which ought to include petrochemical, pharmaceutical, prison etc.
You can not tell me what direction space time curves and all that dark matter black hole nonsense came about because EM effects were not realized until a few decades ago, way after the standard priori was in place. So reality was decided before we had the technology to show us what was actually happening up there. What's stupid is faith in non-falsifiable physics defying assumptions from the gas light era.
jonesdave
5 / 5 (5) Apr 09, 2018
What's stupid is faith in non-falsifiable physics defying assumptions from the gas light era.


Complete and utter rubbish. EM effects weren't known until a few decades ago? What EM effects would these be, pray tell? And how do they manage to do away with the need for DM? Please do not quote the nonsense from Scott & Peratt - that is trivially false, and has been shown to be so. So, what exactly are we missing? Do please explain.
yep
1 / 5 (3) Apr 10, 2018
..anything to raise your head above the surface of the murky, turd-infested pool you inhabit


Please do not project your gourmand scat fetish, it's disquieting.
SkyLight
5 / 5 (5) Apr 10, 2018
You can not tell me what direction space time curves
Correct - the math of GR does that for us. As to the rest of your post, as @jd alludes to, it's too vague to be able to discern what you're trying to say. Do try harder!
yep
1 / 5 (6) Apr 10, 2018
It was the late fifties when we realized space was not the vacuum we supposed. At this time Bostick was doing his dense focused plasma studies with plasmoids showing spiral and barred Galaxy formations in electrical discharge. By the early seventies Birkeland was proven correct on electromagnetic forces in space. Alfven's Plasma cosmology predictions of filamentary structures began to be discovered in the late eighties. The Herschel observations coupled with the understanding of Bennetts pinches and Marklund convections explaining the width of these structures and why galaxies are connected to them like "pearls on string". Langmuir and his work on double layers. It's 150,000 light year long electric currents. It's all these things you are missing because of your faith in authorities assumptions based in Big Bang cosmology that is so flawed at its theological premiss it needs the magic of black holes and dark matter to keep it together.
SkyLight
5 / 5 (6) Apr 10, 2018
Aahhh, that's what you meant. Well, better men than I have tried to show your EU pals the multiplicity of ways in which your theories fall flat on their face... and have failed. Faith is certainly stronger, and stranger, than science.
jonesdave
5 / 5 (7) Apr 10, 2018
^^^^^Total irrelevance to black holes and DM. Please explain how these non-existent currents between galaxies cause their rotation curves. You can't, and neither could Peratt or Scott. How is an essentially charge neutral star being made to rotate at the same velocity as the gas and plasma that surrounds it, by these non-existent currents? You want to charge the star up? How much? Show me the working. What charge? What would that imply for the solar wind? Will the electrons and ions still head in the same direction at the same speed?
Sorry, but this EU/ PC nonsense has been around for decades and has gotten precisely nowhere. It explains nothing. It is dead.
SkyLight
5 / 5 (6) Apr 10, 2018
@jd
What would that imply for the solar wind? Will the electrons and ions still head in the same direction at the same speed?
That question, or one very similar, has been asked before in this forum, and I think it was @cantdrive who replied caustically that the question showed a complete ignorance of the physics of plasmas.

Which rather begs the question of how it is possible for the EU high priests to bamboozle so many EU acolytes with - ahem - theories which show a complete ignorance of physics from the ground up. Ain't nothing so queer as folk...
SkyLight
5 / 5 (6) Apr 10, 2018
I'm reminded of a scene in the film Apollo 13 where Jack Swigert announces that the returning spacecraft is coming in too shallow. When his colleagues question how he can possibly know that when the experts on the ground say their trajectory is OK, he replies "I can add".

The trouble with the EU balderdash is down to this conundrum - they can't add. All the EU BS about huge currents in space and stars being powered by flows of electrons impinging on their surfaces never makes a mention of what causes currents to flow in clouds of plasma which are macroscopically neutral, or where the hell the electrons come from.

Nothing adds up, since half the "theory" is totally missing, and the people charged (pun intended) with pushing the EU agenda - or those who simply believe it - are flatly told that the currents are there ("you can see 'em in the pictures") and since electricity is SOOO much more powerful than gravity that electrical phenomena MUST dominate. QED
SkyLight
5 / 5 (6) Apr 10, 2018
So, the EU offers its' believers no room for deep thought, ignores the need for explanations or for balance, no numbers, no equations to show how things are to be powered, minds closed to things like charge building up so quickly on objects in their theories that they very quickly oppose flows of more charge hurtling toward them from some unknown source powered by who knows what.

Call me old-fashioned, but I'll stick to the mainstream where everything has an explanation. Even DM which, as all sensible people understand, is just a place-holder for a better theory sometime in the future. At least this placeholder, wacky though it may be, is based on sound analysis of observation and accepted and tested theories and results. DM may be wrong (and probably is), but has yet to be definitively disproven.

Situation normal, that's how science progresses, notwithstanding the indignant screams from The Great Scientific Unwashed that not a single trace of DM has yet been found.
Benni
1 / 5 (8) Apr 10, 2018
If you had any kind of reasonable explanation for the motions of the stars orbiting Sgr A*


There is a moon ORBITING a MASS we call Earth, that doesn't prove Earth is a black hole. There are numerous planets ORBITING a stellar orb known as the Sun, that doesn't prove the Sun is a black hole. The Sun orbits the central mass of the galactic barycenter, how does that prove there's a BH at Sgr A*?

SkyLight
4.3 / 5 (6) Apr 10, 2018
There is a moon ORBITING a MASS we call Earth, that doesn't prove Earth is a black hole
How very true. However, if the moon were orbiting the earth every couple of milliseconds, then the Earth would have to be pretty darned heavy, right?

And all that weight concentrated in a sphere the size of the Earth would mean it would collapse upon itself until it wouldn't fill a thimble. As a consequence, believe it or not, the trains would then no longer run on time and televisions would play programs backwards. And you wouldn't be able to lift even a small spoon of Cheerios to your mouth.

Boggles the mind, doesn't it Benni?
SkyLight
4.4 / 5 (7) Apr 10, 2018
But seriously, folks... it's all about speed. Specifically, the speed at which stars - stars! - orbit around the unseen mass at the GC is the clue. Bodies of a few solar masses orbiting another body at the rates observed mean that the unseen partner in the orbits must be VERY, VERY massive indeed.

Using Kepler's and Newton's laws of motion, we can calculate that mass, and it turns out to be 4.1 million solar masses. Together with constraints on the size of the object given by elements of the orbit of the star S2, its' size can be no larger than about 17 light-hours, or 120 AU. A SMBH is the only known (or postulated) object which could fit the bill.

And speaking of bills, that'll be 50 bucks, thanks very much.
jonesdave
5 / 5 (4) Apr 10, 2018
Which rather begs the question of how it is possible for the EU high priests to bamboozle so many EU acolytes with - ahem - theories which show a complete ignorance of physics from the ground up. Ain't nothing so queer as folk...


Indeed. There are so many fundamental errors in EU thinking, that they are trivially shown to be false. This isn't the best place for it, but it has been shown in other fora over the years.
They prattle on about plasma, as if they were experts on the subject yet, to the best of my knowledge, there isn't a single plasma physicist associated with their cult. The closest they've got is a retired EE who is clueless when it comes to astrophysics. His website is a cornucopia of cobblers. To take just one example, his brilliant explanation for the acceleration of the fast solar wind was........... an electric field! Errrr..... electrons one way, ions the other! Is that what we see? Dear me.
http://electric-c...Wind.pdf
SkyLight
5 / 5 (5) Apr 10, 2018
a cornucopia of cobblers
I like that!
electrons one way, ions the other
Hyperionic Maxwell's Demons, anyone?
jonesdave
3.7 / 5 (3) Apr 10, 2018
a cornucopia of cobblers
I like that!


It might have had our American friends scrambling for Google!
jonesdave
4.2 / 5 (5) Apr 10, 2018
There is a moon ORBITING a MASS we call Earth, that doesn't prove Earth is a black hole. There are numerous planets ORBITING a stellar orb known as the Sun, that doesn't prove the Sun is a black hole. The Sun orbits the central mass of the galactic barycenter, how does that prove there's a BH at Sgr A*?


Easy. Kepler, told you before. I'm sure there are more complicated and accurate ways of doing this, but;
assuming the mass of the orbiting body can be ignored (it can), then Mbh = SMA^3/ P^2, where SMA = semi-major axis, in AU, and P = the period of the orbit, in Earth years.
So let's take star S0-2: SMA = 919 AU, P = 14.5 yr. 919^3/ 14.5^2 = 3.69 x 10^6 Msun.
Close enough, methinks.

Stellar Orbits Around the Galactic Center Black Hole
Ghez, A. M. et al.
https://arxiv.org...6130.pdf (see Table 3)
Benni
1 / 5 (7) Apr 10, 2018
it's all about speed. Specifically, the speed at which stars - stars! - orbit around the unseen mass at the GC is the clue


At the 9th photo/animation frame from the top of the page:

http://ircamera.a...nter.htm

"This series of images shows the stars moving very rapidly (~1000 km/sec) in their orbits around the position of Sgr A* (the small yellow cross). On this scale, its motion would be imperceptibly small, so this animation demonstrates that it is truly undetected - there is no source to be seen under the yellow cross."

There being no source to be seen under the yellow cross begs a different explanation than your BH Fantasy. The motions of all those stars are simply a classic function of the barycenter of a gravitationally bound multiple star system.

Read something about how binaries & other multiple star systems function, many of them function at similar speeds as the ones in the photo/animation.

Spacebaby2001
5 / 5 (6) Apr 10, 2018
So hypothetically speaking @Benni, what would happen if 4 million solar masses of mass formed a roughly spherical object about 40 million km in diameter? What would the sphere look like? How would it relate to its surroundings? What would its physical properties be like? I'm curious about the evolution of matter from your perspective.
Benni
1 / 5 (6) Apr 10, 2018
So hypothetically speaking @Benni, what would happen if 4 million solar masses of mass formed a roughly spherical object about 40 million km in diameter?


"Diameter estimates for one at the center of the Milky Way have ranged widely, from as small as the orbit of Mercury to as big as that of Pluto.

Last year, researchers estimated it was as wide as Earth's orbit around the Sun. The new estimate reduces that measurement by half, indicating the diameter of Sgr A*, as the object is known, is about 93 million miles -- same as the distance between Earth and the Sun."

https://www.space...zed.html

What would the sphere look like? How would it relate to its surroundings?


An object at point Sgr A* that is the size of Earth's orbital diameter, would dwarf in size all those stars you see moving in the vicinity in that photo/animation. It would be the largest IMAGE in the photo. So why then doesn't it appear? Simple, no BH.
jimmybobber
5 / 5 (7) Apr 10, 2018
Benni from your source. http://ircamera.a...nter.htm

Could there still be a black hole?????

Even if it doesn't make much energy, there might be a black hole. After 20 years of controversy, we finally managed to measure enough velocities of stars to measure the gravitational field accurately. We can now say: "Certainly! There is a 3 million solar mass black hole."

"However, we can see the black hole in the radio! A super-compact radio source was also discovered."
jimmybobber
5 / 5 (5) Apr 10, 2018
Benni. Your link is also from 2007.
jimmybobber
5 / 5 (4) Apr 10, 2018
Great video of the orbits of stars near the galactic center.
https://www.youtu...PJTo51lM
Benni
1 / 5 (5) Apr 10, 2018
we finally managed to measure enough velocities of stars to measure the gravitational field accurately. We can now say: "Certainly! There is a 3 million solar mass black hole.


When there is no image to support the conclusion, then it only makes sense to change the conclusion to fit the image. The image is that of a multiple star system with stars functioning at typical velocities around a barycenter of gravitationally bound stars, these are very common.

However, we can see the black hole in the radio! A super-compact radio source was also discovered.


Lots of things put out radio waves, e.g., my microwave oven. A couple of year ago I had the occasion to take it apart to repair it, didn't come across any BHs.

Benni. Your link is also from 2007.
.......and Schwarzschild's black hole math is from 1917, I guess that means it should thrown out.

Great video of the orbits of stars near the galactic center.
An animation, I linked you to REAL pics.
Da Schneib
5 / 5 (7) Apr 10, 2018
@jimmy, just a tip: the more current version of the same web page is available here: http://ircamera.a...nter.htm

That's from 2016 as you can see from the link. @Lenni doesn't like to show that one because it has the black hole lighting up when it consumes about the mass of Mercury right in the middle of the page. It makes @Lenni look really, really dumb.

Give it credit, it had to look really hard in order to find a version of the page without that picture.
jimmybobber
5 / 5 (5) Apr 10, 2018
Thanks for the more recent link Da Schneib.
What say you Benni? What's going on in that picture? That is quite an active barycenter.
IwinUlose
5 / 5 (5) Apr 11, 2018
OBSERVATIONAL EVIDENCE


That poor keyboard. How many more of these can it take?
Da Schneib
5 / 5 (4) Apr 11, 2018
Nawww, he uses the "I'm stupid" button. It's the one labeled Caps Lock.
yep
1 / 5 (3) Apr 11, 2018
Aahhh, that's what you meant. Well, better men than I have tried to show your EU pals the multiplicity of ways in which your theories fall flat on their face... and have failed. Faith is certainly stronger, and stranger, than science.


Funny how ironic that is considering the History.

Speaking of history, two great books because you obviously love science being here etc.

Soul of Amber by Alfred Still
"The Background of Electrical Science"
Out of print easy to obtain a wonderful history to give you perspective on your hubris.
And
The Structure of Scientific Revolutions by Thomas Kuhn

jonesdave
5 / 5 (2) Apr 11, 2018
Aahhh, that's what you meant. Well, better men than I have tried to show your EU pals the multiplicity of ways in which your theories fall flat on their face... and have failed. Faith is certainly stronger, and stranger, than science.


Funny how ironic that is considering the History.

Speaking of history, two great books because you obviously love science being here etc.

Soul of Amber by Alfred Still
"The Background of Electrical Science"
Out of print easy to obtain a wonderful history to give you perspective on your hubris.
And
The Structure of Scientific Revolutions by Thomas Kuhn



Why not try something more up to date?
https://www.wiley...19324492

I know the author of one of those chapters. I expect it is very good.
Benni
1 / 5 (6) Apr 11, 2018
TWhat say you Benni?What's going on in that picture?That is quite an active barycenter.
......I'll just let the website say it:

http://ircamera.a...nter.htm

"The lack of energy from the Galactic Center black hole has turned out to be a major challenge to our theories of black holes."

..........when the OBSERVATIONAL EVIDENCE of a REAL IMAGE doesn't exist, it's time to look into changing some standing conclusions as suggested at the website. All those images of visible stars, yet for the strangest of reasons for which an image of a stellar mass that would engulf the orbit of Earth around the Sun is oddly not apparent, a mass which would dwarf in size any star in that multiple star system.

The onus is in you to explain why there is no IMAGE for what you believe exists. Flareups occur all over the Universe, but apparently you think a flareup doesn't occur except in the presence of a BH? Or multiple barycentric star systems?

jonesdave
5 / 5 (4) Apr 11, 2018
a stellar mass that would engulf the orbit of Earth


Wrong.
Spacebaby2001
5 / 5 (3) Apr 11, 2018
Benni could you please answer my question? I was not asking about the actual diameter of the proposed object at Sgr A*.

I'll repeat.

"So hypothetically speaking @Benni, what would happen if 4 million solar masses of mass formed a roughly spherical object about 40 million km in diameter? What would the sphere look like? How would it relate to its surroundings? What would its physical properties be like? I'm curious about the evolution of matter from your perspective."
Benni
1 / 5 (4) Apr 11, 2018
I was not asking about the actual diameter of the proposed object at Sgr A*.
......so why then did you bring it up? All I did was correct your assumption that the BH Experts at https://www.space...zed.html contradict your assumption of a 40 million diameter mass, but I guess you have a better telescope?

I'll repeat.

"So hypothetically speaking @Benni, what would happen if 4 million solar masses of mass formed a roughly spherical object about 40 million km in diameter?
Correction by your Experts is 150 million.

What would the sphere look like?
......an object 150 km in diameter

How would it relate to its surroundings?
An image that would be the largest in the pics

What would its physical properties be like?
It would have the appearance being that of the largest image in the pics.

[
jonesdave
5 / 5 (4) Apr 11, 2018
Correction by your Experts is 150 million.


Wrong.
Spacebaby2001
5 / 5 (2) Apr 11, 2018
You do understand what hypothetical means right? I'm trying to pull out of you exactly what you think happens to mass as it coalesces to extreme densities. If anywhere in the universe 4 million solar masses worth of mass coalesce into a single roughly spherical form with an average diameter of 40 million km what would this object look like? What would the force of gravity be at its surface? What would happen to the matter contained in this object?

You don't think black holes exist, fine. You do presumably believe in matter, gravity and the relationship between the two as we understand it. That being said there's nothing stopping you from answering the questions about this hypothetical object somewhere in the universe. This is just a thought experiment so I can better understand your perspective.
jimmybobber
5 / 5 (2) Apr 11, 2018
You want a picture of a black hole. What kind of picture? What wavelengths of electromagnetic radiation. Your linked article discusses how difficult it is to observe certain wavelengths in that area of space. They did observe some radio waves and also observed the "flareup" as well which further provides evidence something is there.
What would it take for you to accept there is most likely a black hole there????
Benni
1 / 5 (3) Apr 11, 2018
Correction by your Experts is 150 million.


Wrong.
........yer right about something for a change, it's 300 million, a diameter is twice that of the radius.
jonesdave
5 / 5 (3) Apr 11, 2018
Correction by your Experts is 150 million.


Wrong.
........yer right about something for a change, it's 300 million, a diameter is twice that of the radius.


Wrong.
Benni
1 / 5 (3) Apr 11, 2018
What would it take for you to accept there is most likely a black hole there?


....an image of an object 300 million km in diameter. An image this size would of course dwarf in size any of those stars in the already visible orbitals of the star system.

If anywhere in the universe 4 million solar masses worth of mass coalesce into a single roughly spherical form with an average diameter of 40 million km what would this object look like?


You said it, an image that is 40 million km. What's the big mystery here? Are you trying to suggest there is a way a BH can play tricks on telescopes & show only images of non-BH stellar objects?

jimmybobber
5 / 5 (6) Apr 11, 2018
https://en.wikipe...arius_A*

From the motion of star S2, the object's mass can be estimated as 4.1 million solar masses.[3] (The corresponding Schwarzschild radius is 0.08 AU/12 million km/7.4 million miles; 17 times bigger than the radius of the Sun.)

jonesdave
5 / 5 (6) Apr 11, 2018
Are you trying to suggest there is a way a BH can play tricks on telescopes & show only images of non-BH stellar objects?


Notice the childlike inability to understand the word 'black' here folks. And also relying on a 2005 press release for his faulty beliefs about the size of the BH. I already explained that to him upthread, and even tracked down the paper. The size was a maximum based on 3.5mm radio observations. Later work superseded this, and got the size down to ~ 37 microarcsecs. If my maths is correct, then 37 microarcsecs equates to ~ 0.3 AU (45m km) diameter. So, centre it on the Sun, and we have an object that reaches roughly halfway to Mercury.

Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre
Doeleman, S. S. et al.
https://arxiv.org...2442.pdf

Spacebaby2001
5 / 5 (4) Apr 11, 2018
Benni, could you please answer the other questions about this hypothetical object specifically the gravity at its surface?
Benni
1 / 5 (3) Apr 11, 2018
The corresponding Schwarzschild radius is 0.08 AU/12 million km/7.4 million miles; 17 times bigger than the radius of the Sun.


24 mil km/ 14,8 mil miles diameter............pretty big, bigger than all the stars that are imaged as orbiting point Sgr A*. Odd then that no image of anything can be seen at Sgr A*, only the much smaller orbiting the stars. Maybe you can explain this?
SkyLight
5 / 5 (4) Apr 11, 2018
@yep
The Structure of Scientific Revolutions by Thomas Kuhn
Read Kuhn over forty years ago. Great book.

I wouldn't waste my time with your other suggestion, a book written by a guy at the end of his life in 1944 and which gives some kind of an overview of the history of electricity (?). Probably takes pride of place on your bookshelf, though.
Benni
1 / 5 (2) Apr 11, 2018
Benni, could you please answer the other questions about this hypothetical object specifically the gravity at its surface?


The Inverse Square Law. Gravity is maximum at the surface & zero at the center.
jonesdave
5 / 5 (5) Apr 11, 2018
Benni, could you please answer the other questions about this hypothetical object specifically the gravity at its surface?


That would involve Benni doing maths, which he invariably buggers up. I'll take a stab in the dark and go for ~ 3.7 million m/s, assuming a Rsch of 12m km.
jonesdave
5 / 5 (4) Apr 11, 2018
The corresponding Schwarzschild radius is 0.08 AU/12 million km/7.4 million miles; 17 times bigger than the radius of the Sun.


24 mil km/ 14,8 mil miles diameter............pretty big, bigger than all the stars that are imaged as orbiting point Sgr A*. Odd then that no image of anything can be seen at Sgr A*, only the much smaller orbiting the stars. Maybe you can explain this?


Already have. They are red supergiants. Look them up. Radii of 100s to 1000s of times that of the Sun.
jimmybobber
5 / 5 (3) Apr 11, 2018
The corresponding Schwarzschild radius is 0.08 AU/12 million km/7.4 million miles; 17 times bigger than the radius of the Sun.


24 mil km/ 14,8 mil miles diameter............pretty big, bigger than all the stars that are imaged as orbiting point Sgr A*. Odd then that no image of anything can be seen at Sgr A*, only the much smaller orbiting the stars. Maybe you can explain this?


It's not pretty big at all it's just 17 times larger in radius than the sun.

jimmybobber
5 / 5 (3) Apr 11, 2018
Benni so your saying the orbits of the stars surrounding the black hole actually cross the event horizon at 7.4 millions miles radius?
jimmybobber
5 / 5 (4) Apr 11, 2018
Benni.
https://en.wikipe...2_(star)
"Source 2 (abbreviated S2), also known as S0–2, is a star that is located close to the radio source Sagittarius A*, orbiting it with an orbital period of 15.56 ± 0.35 years and a pericenter distance of 17 light hours (18 Tm or 120 AU)—an orbit with a period only about 30% longer than that of Jupiter around the Sun, but coming no closer than about four times the distance of Neptune from the Sun. As of 2002, its mass was initially estimated by the European Southern Observatory (ESO) to be approximately 15 M☉.[3]"

4*(Distance of Neptune from the Sun) ~ 11 billions miles.
jonesdave
5 / 5 (7) Apr 11, 2018
Benni, could you please answer the other questions about this hypothetical object specifically the gravity at its surface?


That would involve Benni doing maths, which he invariably buggers up. I'll take a stab in the dark and go for ~ 3.7 million m/s, assuming a Rsch of 12m km.


We could then go on to calculate the escape velocity from such an object:
Ve = SQRT(2GM/ r). We know G and M and r, so, with much rounding up and down in my BOTE calculation, I get 2.9 x 10^8 m/s. Yikes, that is very close to the speed of light! Surprise, surprise.
Spacebaby2001
5 / 5 (6) Apr 11, 2018
We could then go on to calculate the escape velocity from such an object:
Ve = SQRT(2GM/ r). We know G and M and r, so, with much rounding up and down in my BOTE calculation, I get 2.9 x 10^8 m/s. Yikes, that is very close to the speed of light! Surprise, surprise.


I'm hesitant to pass judgment on topics I'm not thoroughly educated in, however the line of logic regarding mass and gravity that leads to the prediction of black holes seems so intuitive to me.

See Benni, Jonesdave response is direct, clear, and he even shows a portion of the work. That together with, my limited general knowledge of the subject, and the work of a myriad of researchers and scientists is why I chose to trust their work, that black holes are fact, and that Sgr A* is one of them albeit a big honking example of one.
691Boat
5 / 5 (7) Apr 11, 2018
Benni logic:
I hold a magnet in each hand. When i push the north pole of each magnet towards each other, I observe that they repel and push away from one another. But, because I have never seen a picture of a magnetic field, it doesn't exist. Sure, we can use iron filings to show that it is actually there, but I don't believe that because I haven't seen a picture of the actual magnetic field.
Benni
1 / 5 (5) Apr 11, 2018
black holes are fact, and that Sgr A* is one of them albeit a big honking example of one.


It's not pretty big at all it's just 17 times larger in radius than the sun.


Well, which is it: "not pretty big" or "albeit a big honking example".......be clear.

my limited general knowledge of the subject, and the work of a myriad of researchers and scientists is why I chose to trust their work, that black holes are fact, and that Sgr A* is one of them albeit a big honking example of one.
.........your problem is obvious, jonesy works up funny farm math & you swallow it hook line & sinker.

I don't know why it is incomprehensible to you that according to the Inverse Square Law gravity is maximum at the surface of a stellar mass & zero at the center, but if that is not "clear" to you then you are beyond hopeless when it comes to 1st semester physics, jonesy has the same problem.

By the way, have you ever seen a Differential Equation you could solve?

jimmybobber
5 / 5 (7) Apr 11, 2018
Are you for real Benni.
I said it's not that big compared to our sun. He said it's pretty big for a black hole. Two different points of reference there that you can't seem to discern. Is English your first language?

I'm convinced you have to be trolling this forum. If not I feel really bad for you.
jonesdave
5 / 5 (5) Apr 11, 2018
By the way, have you ever seen a Differential Equation you could solve?


You can't even do simple maths, let alone DEs, windbag. As proven. And what the hell has the gravity at the centre of mass got to do with anything? If you have a 4m Msun mass in a radius of 1.2m km, then light is not escaping it. End of story. Want me to walk you through the maths?
jimmybobber
5 / 5 (6) Apr 11, 2018
Benni. In my experience most differential equations of importance do not have closed form solutions and have to be solved numerically.
Benni
1 / 5 (6) Apr 11, 2018
24 mil km/ 14,8 mil miles diameter............pretty big, bigger than all the stars that are imaged as orbiting point Sgr A*. Odd then that no image of anything can be seen at Sgr A*, only the much smaller orbiting the stars. Maybe you can explain this?


It's not pretty big at all it's just 17 times larger in radius than the sun.


Why don't you answer the question? Why we can plainly see the smaller orbital stars but not the much bigger mass you claim exists at Sgr A* that is 17 times larger in radius than the sun?
jimmybobber
5 / 5 (9) Apr 11, 2018
Because it's a black hole and electromagnetic radiation cannot escape it. What do you expect to see?
jonesdave
5 / 5 (6) Apr 11, 2018
Because it's a black hole and electromagnetic radiation cannot escape it. What do you expect to see?


Bunnies. Lots and lots of bunnies.
Benni
1 / 5 (5) Apr 11, 2018
Because it's a black hole and electromagnetic radiation cannot escape it. What do you expect to see?


.................a round black orb surrounded by a luminous doughnut shaped accretion disc up to 5 times the diameter of the round black orb, you know, the classic description of a BH.

So, let's see here, if the BH is 24 mil km/ 14,8 mil miles diameter, this means the luminous accretion disc can be 120 mil km/74 mil miles in diameter. Thoughts?
691Boat
5 / 5 (5) Apr 11, 2018
jimmybobber
5 / 5 (7) Apr 11, 2018
Benni you do realize not all black holes have accretion disks right?
Benni
1 / 5 (6) Apr 11, 2018
Benni you do realize not all black holes have accretion disks right?


No, I did not know this. How do you know this?

Can you explain why something BLACK 24 mil km/ 14,8 mil miles diameter in the most luminous part of the galaxy, is undetectable with regard to blocking out background light? I guess you could also consider this to be in response to the query posed at:

http://ircamera.a...nter.htm

8th pic frame from the top of the page:

"Ever increasing resolution showed the black hole is not the energy source. The brightest source in the very high resolution near infrared image to the right is IRS 7, a red supergiant that puts out most of its energy in the near infrared."

According to the the website animations & pics, the BH should be located just a short distance below IRS 7 which is only somewhat larger in diameter than what the BH is supposed to be. I would expect to see a sharply distinguishable black orb.
jimmybobber
5 / 5 (8) Apr 11, 2018
I googled it.
Da Schneib
5 / 5 (7) Apr 11, 2018
I googled it.
Classic.
jimmybobber
5 / 5 (7) Apr 11, 2018
I'm done. Good luck Benni. I admire your perseverance.
Da Schneib
5 / 5 (7) Apr 11, 2018
A good performer always knows when the show's over. Stick around, @jimmy. I like your chops.
yep
1 / 5 (2) Apr 12, 2018
@yep
The Structure of Scientific Revolutions by Thomas Kuhn
Read Kuhn over forty years ago. Great book.

I wouldn't waste my time with your other suggestion, a book written by a guy at the end of his life in 1944 and which gives some kind of an overview of the history of electricity (?). Probably takes pride of place on your bookshelf, though.


And that is why we repeat our follies, arrogance and willful ignorance. That book is as relevant today as when it was written. The fact he was at the end of his life gives more credence to what he wrote not less, especially considering the era in which he lived. I can only hope you reconsider your thinking on this. It gives an incredible perspective on science and its advancement as I beliveve it may have given Kuhn.
Benni
1 / 5 (7) Apr 12, 2018
I'm done. Good luck Benni. I admire your perseverance.


The CONCLUSION being that you cannot prove point Sgr A* is NOT a BARYCENTER.
jimmybobber
5 / 5 (8) Apr 12, 2018
Benni.
en.wikipedia.org...

"Proof by assertion, sometimes informally referred to as proof by repeated assertion, is an informal fallacy in which a proposition is repeatedly restated regardless of contradiction.[1] Sometimes, this may be repeated until challenges dry up, at which point it is asserted as fact due to its not being contradicted (argumentum ad nauseam).[2] In other cases, its repetition may be cited as evidence of its truth, in a variant of the appeal to authority or appeal to belief fallacies.[3]"

And furthermore the burden of proof is on you to prove it is a barycenter not me to prove it's not. Feel free to link some articles to support your claim.
Benni
1 / 5 (5) Apr 12, 2018
And furthermore the burden of proof is on you to prove it is a barycenter not me to prove it's not.


Really? Why so is "proof" a one way street with you? You have ZERO OBSERVATIONAL EVIDENCE in support of your claim that a BH of 24 mil km/ 14,8 mil miles diameter exists at point Sgr A*, no big round black orb blocking out background stars, no accretion disc, & no classic x-ray source that would be expected, in short everything that is expected for EVIDENCE of a BH is absent in ALL the pics & data at:

http://ircamera.a...nter.htm

..........but I guess you are one of those who would believe that the absence of evidence & data for a BH at point Sgr A* is proof it is not the BARYCENTER of the obvious multiple star system orbiting Sgr A*.

Just gotta love you guys living on the plantation of funny farm pseudo-science, your just so much fun & entertainment to talk to.

jimmybobber
5 / 5 (6) Apr 12, 2018
Link some scientific articles that prove it's a barycenter.
Your link concludes there is a black hole there. You just like looking at the pretty pictures and making your own conclusion.
Benni
1 / 5 (5) Apr 12, 2018
Link some scientific articles that prove it's a barycenter.
Your link concludes there is a black hole there. You just like looking at the pretty pictures and making your own conclusion.


The same conclusions as the captions alongside the pics.

Your problem is with the website having the audacity to put up such pics & data that causes one to follow the logical path to a conclusion that if there is no observational evidence in support of a BH, what then explains the orbital patterns of stars around point Sgr A*, only one thing a classic BARYCENTER of the stars at point Sgr A*.

Do some reading up on orbital mechanics, then come back here & tell me why Sgr A* cannot be the barycenter of that multiple star group. So far you haven't even demonstrated you know what a BARYCENTER is.
ShotmanMaslo
5 / 5 (6) Apr 12, 2018
Can you explain why something BLACK 24 mil km/ 14,8 mil miles diameter in the most luminous part of the galaxy, is undetectable with regard to blocking out background light?


Because your picture has a resolution of 1 arcsecond, which is 11,000,000 million kilometers. Anything smaller than that and you will not be able to resolve it. Your picture covers a huge 64 light years wide area. You need a million times more detailed picture to even begin to see the big black orb of the black hole. This was already explained to you quantitatively and yet you willfully persist in ignorance. What a shameful display.
jimmybobber
5 / 5 (8) Apr 12, 2018
Benni from your link.

"Even if it doesn't make much energy, there might be a black hole. After 20 years of controversy, we finally managed to measure enough velocities of stars to measure the gravitational field accurately. We can now say: "Certainly! There is a 3 million solar mass black hole."

Your looking at the text next to the pictures but your failing to see the overall conclusion.
Enthusiastic Fool
5 / 5 (8) Apr 12, 2018
Benni has been thoroughly routed in just about every engagement I've read since he started linking the IR Camera page. Is he paid by Physorg to generate comments and traffic for the article? Pages without lunacy seem to lack in commentary and the conflicts seem to drive discussion, one-sided as it is.
SkyLight
5 / 5 (8) Apr 12, 2018
Do some reading up on orbital mechanics, then come back here & tell me why Sgr A* cannot be the barycenter of that multiple star group
The orbital mechanics of stars orbiting around a barycenter are very well understood in observations of globular clusters and, since 2010 "it became possible to directly compute, star by star, N-body simulations of a globular cluster over the course of its lifetime." [Wiki].

Stars moving within a globular cluster follow paths which are not simple ellipses, since the effects of stars close by (globular clusters are very dense assemblages of stars) would rapidly perturb such paths. Movements of stars within such a cluster are best described as random; secondly, their "average" velocities are in the low tens of km/s.

Within the GC, however, the S-stars do follow elliptical paths, with velocities of up to 5000 km/s (star S2 at closest approach). Only a SMBH could contain the 3-4 million Msolar necessary within the 17 AU upper limit of radius.
jimmybobber
5 / 5 (6) Apr 12, 2018
thanks for posting that SkyLight. Believe it or not I'm learning a lot arguing with Benni and viewing posts from others.
SkyLight
5 / 5 (6) Apr 12, 2018
Believe it or not I'm learning a lot arguing with Benni and viewing posts from others.
That's the whole point of these discussions! ;-)
Benni
1 / 5 (5) Apr 12, 2018
your failing to see the overall conclusion.


What "overall conclusion"? Oh, you mean:

ZERO OBSERVATIONAL EVIDENCE in support of claims that a BH of 24 mil km/ 14,8 mil miles diameter exists at point Sgr A*, no big round black orb blocking out background stars, no accretion disc, & no classic x-ray source that would be expected, in short everything that is expected as EVIDENCE of a BH is absent in ALL the pics & data.

It would seem there is a growing cadre of neophytes living here who believe lack of evidence is the salient point proving there must be a BH at point Sgr A*, PRECISELY BECAUSE THERE IS NO EVIDENCE.

Like I stated above, you characters have become so much fun because you are just so entertaining you try to twist LACK OF OBSERVATIONAL EVIDENCE into proof of evidence for your cumbersome arguments.

691Boat
5 / 5 (6) Apr 12, 2018
jonesdave
5 / 5 (4) Apr 12, 2018
no accretion disc, & no classic x-ray source


Wrong.
jimmybobber
5 / 5 (4) Apr 12, 2018
Benni. Let's start from scratch. Please state your hypothesis regarding Sgr A Then we will investigate further.
jimmybobber
5 / 5 (4) Apr 12, 2018
So let's forget about black holes and just using the research data you posted state your hypothesis.
jonesdave
4.3 / 5 (6) Apr 12, 2018
So let's forget about black holes and just using the research data you posted state your hypothesis.


This is almost where I started this current round of Benni's scientific illiteracy, some weeks ago. I noted that the Event Horizon Telescope now has all of its data, and should report this year. They have the resolution to see the EH. I wanted to know what the #physicscranks were predicting. Benni has never answered this, as far as I can remember. Cantthink obviously thinks they'll make up the data just to deny his Velikovskian EU woo. Predictably. So, it really would be interesting to know what the aforementioned cranks believe it will see.
Benni
1 / 5 (4) Apr 12, 2018
Benni. Let's start from scratch. Please state your hypothesis regarding Sgr A


The orbital patterns of stars around point Sgr A* are a classic pattern of a multiple star system with BARYCENTER of the stars at point Sgr A*. The orbital mechanics is easily established at pics 9 & 10 as highlighted by the caption:

"If we zoom in on Sgr A*, we see better the very high speeds of the stars that come very close. There is no trace of the central black hole, though, other than the effect of its mass on the stellar orbits."

So, if there is no trace of a BH mass (or any mass at all) at point Sgr A*, then Sgr A* is the barycenter of the stars imaged in the 9th & 10th pics from the top of the page time lapse pics.

http://ircamera.a...nter.htm
jimmybobber
5 / 5 (3) Apr 12, 2018
Please just state your hypothesis.

jonesdave
5 / 5 (5) Apr 12, 2018
The orbital patterns of stars around point Sgr A* are a classic pattern of a multiple star system with BARYCENTER of the stars at point Sgr A*. The orbital mechanics is easily established at pics 9 & 10 as highlighted by the caption:


No, they aren't. As has already been explained. And nobody, other than you, believes that to be the case.
And then you totally contradict yourself by saying, "So, if there is ***no trace of a BH mass*** (or any mass at all) at point Sgr A*...", despite having said in the previous sentence, "There is no trace of the central black hole, though, other than the ***effect of its mass on the stellar orbits***."

Sorry, but if you can't even agree with yourself from sentence to sentence, then it is clearly a waste of time trying to understand whatever it is that you believe.

Benni
1 / 5 (5) Apr 12, 2018
Please just state your hypothesis.


The orbital patterns of stars around point Sgr A* are a classic pattern of a multiple star system with BARYCENTER of the stars at point Sgr A*. The orbital mechanics is easily established at pics 9 & 10 as highlighted by the caption:

"If we zoom in on Sgr A*, we see better the very high speeds of the stars that come very close. There is no trace of the central black hole, though, other than the effect of its mass on the stellar orbits."

So, if there is no trace of a BH mass (or any mass at all) at point Sgr A*, then Sgr A* is the barycenter of the stars imaged in the 9th & 10th pics from the top of the page time lapse pics.


jimmybobber
5 / 5 (3) Apr 12, 2018
That's a bit more than just a simple hypothesis.
jonesdave
5 / 5 (3) Apr 12, 2018
Please just state your hypothesis.



He hasn't got one.
Benni
1 / 5 (4) Apr 12, 2018
That's a bit more than just a simple hypothesis.


At least it's clearly stated. Your turn.
691Boat
5 / 5 (6) Apr 12, 2018
@Benni:
With that number of stars, assuming there is no large single mass at the center, why don't we see wobbles in the orbitals we have been able to measure? Surely if there was no single overpowering mass in the center of it, the large stars in the area would have an appreciable effect on other stars, thus changing their orbits slightly, correct?
691Boat
5 / 5 (6) Apr 12, 2018
@Benni:
I would also imagine that you have evidence of the ~4M solar masses worth of stars in the nearby neighborhood that would cause the effects we can observe near Sag A*, if it actually is only a barycenter, correct?
jonesdave
4.3 / 5 (6) Apr 12, 2018
At least it's clearly stated.


No, it isn't. So what is at the centre of the galaxy, the object known as Sgr A*? You know, the one that affects the orbits of all those stars, and occasionally flares up in IR and X-ray? What will the EHT see?
Benni
1 / 5 (6) Apr 12, 2018
@Benni:
With that number of stars, assuming there is no large single mass at the center, why don't we see wobbles in the orbitals we have been able to measure? Surely if there was no single overpowering mass in the center of it, the large stars in the area would have an appreciable effect on other stars, thus changing their orbits slightly, correct?


Explain "wobbles".

Just go study how the orbital mechanics of multiple star systems function, they're not all the same. But of course there is a point where multiple star systems with a barycenter change with changing #s of stars entering & exiting the system.
jimmybobber
5 / 5 (6) Apr 12, 2018
How is this for your hypothesis? It's a first pass.. We can refine it.

"The center of Sgr A is the center of mass of an N-body system of stars in Sgr A"
jonesdave
5 / 5 (5) Apr 12, 2018
How iss this for your hypothesis?

"The center of Sgr A is the center of mass of an N-body system of stars in Sgr A"


In which case the hypothesis already fails. It cannot explain the orbits and orbital velocities of those central stars. Next.
jimmybobber
5 / 5 (6) Apr 12, 2018
I agree jones but i'm trying to force Benni to use the scientific method to see his errors.
Benni
1 / 5 (5) Apr 12, 2018
How is this for your hypothesis? It's a first pass.. We can refine it.

"The center of Sgr A is the center of mass of an N-body system of stars in Sgr A"


No, because these are not my words, my words don't need refining, I'm a Nuclear/Electrical Engineer having spent six years in Engineering School with almost two years of continuing ed credits beyond that, thus you are not qualified to refine my words.
jimmybobber
5 / 5 (4) Apr 12, 2018
Was i wrong or you just don't like me re-wording your hypothesis?
jonesdave
5 / 5 (3) Apr 12, 2018
Was i wrong or you just don't like me re-wording your hypothesis?


What hypothesis? Does it involve bunnies? They usually do.
Benni
1 / 5 (6) Apr 12, 2018
Was i wrong or you just don't like me re-wording your hypothesis?


My words didn't need re-wording, they are always as clear as the OBSERVATIONAL EVIDENCE at http://ircamera.a...nter.htm that there is no BH at point Sgr A*
jonesdave
5 / 5 (6) Apr 12, 2018
Was i wrong or you just don't like me re-wording your hypothesis?


My words didn't need re-wording, they are always as clear as the OBSERVATIONAL EVIDENCE at http://ircamera.a...nter.htm that there is no BH at point Sgr A*


Yes there is. The effects seen on the orbits of the stars around it. That cannot be explained by some nonsense about a massless barycentre. And also the occasional flares seen in IR and X-ray from something that isn't a star.
jimmybobber
5 / 5 (7) Apr 12, 2018
Anyhow I can see this road is a dead end.
I agree with Jones. Your hypothesis falls apart shockingly quickly.

jimmybobber
5 / 5 (6) Apr 12, 2018
And I don't believe you responded to SkyLight's post here:

"The orbital mechanics of stars orbiting around a barycenter are very well understood in observations of globular clusters and, since 2010 "it became possible to directly compute, star by star, N-body simulations of a globular cluster over the course of its lifetime." [Wiki].

Stars moving within a globular cluster follow paths which are not simple ellipses, since the effects of stars close by (globular clusters are very dense assemblages of stars) would rapidly perturb such paths. Movements of stars within such a cluster are best described as random; secondly, their "average" velocities are in the low tens of km/s.

Within the GC, however, the S-stars do follow elliptical paths, with velocities of up to 5000 km/s (star S2 at closest approach). Only a SMBH could contain the 3-4 million Msolar necessary within the 17 AU upper limit of radius."
jonesdave
5 / 5 (7) Apr 12, 2018
Interesting paper here on NIR flares seen precisely where there is nothing (unless you believe Sgr A* is a black hole):

Near-infrared flares from accreting gas around the supermassive black hole at the Galactic Centre
Genzel, R. et al
https://arxiv.org...0821.pdf
jimmybobber
5 / 5 (6) Apr 12, 2018
very nice link. No mention of bunnies sadly.
Benni
1 / 5 (4) Apr 13, 2018
Interesting paper here on NIR flares seen precisely where there is nothing (unless you believe Sgr A* is a black hole):


Even our own sun generates flares, that doesn't make it a BH. Almost every star in the universe generates flares from time to time, that doesn't make them a BH.

So what if a background or foreground star near the galactic center point Sgr A* generates a flare, there are millions of stars in that area of the galaxy any one of which can generate flares. Likewise, so what if there are radio noise sources that also come from the area of the multiple star cluster at point Sgr A*, all stars do this, our Sun also generates radio frequency noise but it's obviously not a BH.
jimmybobber
5 / 5 (6) Apr 13, 2018
https://www.nasa....ter.html

"The new study reveals that Sagittarius A* (Sgr A* for short) has been producing one bright X-ray flare about every ten days. However, within the past year, there has been a ten-fold increase in the rate of bright flares from Sgr A*, at about one every day. This increase happened soon after the close approach to Sgr A* by a mysterious object called G2"

This doesn't prove that the black hole snacked on G2. It could be a coincidence but nevertheless it is interesting.
jimmybobber
5 / 5 (5) Apr 13, 2018
http://earthsky.o...ole-sgra

"One of the most mysterious and interesting known locations in our neighborhood of space is the center of our home galaxy, the Milky Way. It's thought to contain a supermassive black hole, with a mass of some 4 million suns. Astronomers call this region and its possible black hole Sagittarius A* (aka Sgr A*, pronounced Sagittarius A-star). In 2016, Farhad Yusef-Zadeh of Northwestern University reported his discovery of an unusual filament in this region. The filament is about 2.3 light-years long and appears to curve around the site of the black hole."
SkyLight
5 / 5 (7) Apr 13, 2018
Even our own sun generates flares, that doesn't make it a BH. Almost every star in the universe generates flares from time to time, that doesn't make them a BH.

So what if a background or foreground star near the galactic center point Sgr A* generates a flare, there are millions of stars in that area of the galaxy any one of which can generate flares. Likewise, so what if there are radio noise sources that also come from the area of the multiple star cluster at point Sgr A*, all stars do this, our Sun also generates radio frequency noise but it's obviously not a BH.
Benni, you are the quintessence, the stereotype, of the dumbass engineer who has gathered a few factoids and proceeds to blather with no wit, intelligence or wisdom about those "facts" as if he knew what he was talking about.

Personally, I've met shedloads of such people, whom one can very easily spot once they open their mouths. Walking away is the usual gambit, but I guess we're stuck with Benni the Bloop.
jimmybobber
5 / 5 (7) Apr 13, 2018
I've worked with many incompetent engineers with impressive degrees. I'm guessing Benni was a "memorize the equation" type of student. I found most students in my Physics courses would indeed simply memorize equations without learning how to derive them.

I knew someone who passed Calculus but didn't understand what a derivative was.
cardzeus
5 / 5 (3) Apr 13, 2018
Benni should really be banned
jimmybobber
5 / 5 (5) Apr 13, 2018
We all know at the center of the galaxy is the mythical planet Sha Ka Ree.
SkyLight
5 / 5 (5) Apr 13, 2018
I knew someone who passed Calculus but didn't understand what a derivative really was.
Calculus by Michael Spivak!
Benni
1 / 5 (5) Apr 13, 2018
In 2016, Farhad Yusef-Zadeh of Northwestern University reported his discovery of an unusual filament in this region. The filament is about 2.3 light-years long and appears to curve around the site of the black hole."


There's nothing new or UNCOMMON about "filaments", they exist all over the galaxy & in between galaxies, in fact they are they biggest structures in the Universe, how do such filaments prove BHs exist?.

I guess you now imagine that because a filament is coincidentally found within the multiple star system at point Sgr A*, this proves a BH exists there? So how do FILAMENTS prove the existence of BHs?

I guess you haven't thought about the statistical probability about NOT FINDING a FILAMENT at point Sgr A*, beings how it is FILAMENTS are the most common sources of mass in the Universe.
jimmybobber
5 / 5 (7) Apr 13, 2018
The filament appears to curve around your "barycenter." Did you even read the article?
It's just more evidence pointing to a massive object there.
jonesdave
5 / 5 (6) Apr 13, 2018
And Benni, as usual, isn't thinking at all. Just parroting some crank or other, with nothing scientific to back up his nonsensical claims. And there isn't a multiple star system. These are all individual stars, on their own orbits. Look up the definition.
jimmybobber
5 / 5 (7) Apr 13, 2018
Benni. I have googled for any evidence supporting your hypothesis and I cannot find one site that does.
Benni
1 / 5 (5) Apr 13, 2018
The filament appears to curve around your "barycenter." Did you even read the article?
It's just more evidence pointing to a massive object there.


Well then, we'll just have to leave it to your fantasy that a BH is found at the end of every FILAMENT, in the meantime there still remains no OBSERVATIONAL EVIDENCE there is a BH at point Sgr A*, but i do have a way out for you, here follow me:

At the one end of the "filament" at point Sgr A* lies the most dense cloud of Cosmic Fairy Dust within the entire galaxy. This cloud is so dense that it causes stars & filaments to orbit around it, yet it is so transparent it allows background stars to be observed directly through point Sgr A* from the opposite side as is seen at http://ircamera.a...nter.htm 8th photo from the top of the page.

This Cosmic Fairy Dust supplies all the inferred force of gravity necessary for all the OBSERVATIONAL EVIDENCE supplied by our favorite website.

jimmybobber
5 / 5 (4) Apr 13, 2018
Benni I never said "a BH is found at the end of every FILAMENT!"
They are not talking about a galactic filament in the article. So you didn't read it.
jonesdave
5 / 5 (3) Apr 13, 2018
in the meantime there still remains no OBSERVATIONAL EVIDENCE there is a BH at point Sgr A*


Wrong.

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