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  • #16
    Originally posted by seer View Post
    I see Jesus' face in it! The Bible is true?
    In the black Hole, maybe the clouds? spilled coffee? or the burnt toast?
    Last edited by shunyadragon; 04-12-2019, 09:48 AM.
    Glendower: I can call spirits from the vasty deep.
    Hotspur: Why, so can I, or so can any man;
    But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

    go with the flow the river knows . . .

    Frank

    I do not know, therefore everything is in pencil.

    Comment


    • #17
      ffnrg2z8pir21.jpg

      Comment


      • #18
        I was wondering what ‘shadow’ meant.
        When surrounded by a transparent emission region, black holes are expected to reveal a dark shadow caused by gravitational light bending and photon capture at the event horizon. To image and study this phenomenon, we have assembled the Event Horizon Telescope, a global very long baseline interferometry array observing at a wavelength of 1.3 mm. This allows us to reconstruct event-horizon-scale images of the supermassive black hole candidate in the center of the giant elliptical galaxy M87. We have resolved the central compact radio source as an asymmetric bright emission ring with a diameter of 42±3 μas, which is circular and encompasses a central depression in brightness with a flux ratio 10:1. The emission ring is recovered using different calibration and imaging schemes, with its diameter and width remaining stable over four different observations carried out in different days. Overall, the observed image is consistent with expectations for the shadow of a Kerr black hole as predicted by general relativity. The asymmetry in brightness in the ring can be explained in terms of relativistic beaming of the emission from a plasma rotating close to the speed of light around a black hole. We compare our images to an extensive library of ray-traced general-relativistic magnetohydrodynamic simulations of black holes and derive a central mass of M=(6.5±0.7)×109 Me. Our radio- wave observations thus provide powerful evidence for the presence of supermassive black holes in centers of galaxies and as the central engines of active galactic nuclei. They also present a new tool to explore gravity in its most extreme limit and on a mass scale that was so far not accessible.
        https://iopscience.iop.org/article/1...41-8213/ab0ec7

        Some special characters lost in translation.

        Some addition reading needed!
        Last edited by firstfloor; 04-12-2019, 10:45 AM.
        “I think God, in creating man, somewhat overestimated his ability.” ― Oscar Wilde
        “And if there were a God, I think it very unlikely that He would have such an uneasy vanity as to be offended by those who doubt His existence” ― Bertrand Russell
        “not all there” - you know who you are

        Comment


        • #19
          Originally posted by firstfloor View Post
          I was wondering what ‘shadow’ meant.


          https://iopscience.iop.org/article/1...41-8213/ab0ec7

          Some special characters lost in translation.

          Some addition reading needed!
          Yep - this is an amazing result. Just the math and programming required to put the data together is incredible. I've seen m87 through my amateur scope. It is impressive all on its own. It is a huge elliptical, perhaps 200 times the mass of the milky way and over 2x as big in size (over 200,000 light years) It is the center of mass for one of 3 subgroups of the virgo cluster, a massive gravitationally bound group of galaxies in the constellation virgo, many of which are visible in small to medium sized telescope (6 - 10 inches aperture). The spring and early summer is a great time of year to see these galaxies, including m87. It was not long ago that we were just getting high resolution hubble images of the incredible relativistic jet that streams out from the massive black hole imaged for the first time by Event Horizon.

          Below is an annotated photo of the cluster, with m87 found in the lower center portion.

          Virgo-Cluster-galaxies-768x768.jpg

          below is a high resolution image of the jet from the black hole:

          The-radio-jet-of-the-elliptical-galaxy-M87-is-also-visible-in-the-optical-range-Detailed.jpg


          Jim
          Last edited by oxmixmudd; 04-12-2019, 12:32 PM.
          My brethren, do not hold your faith in our glorious Lord Jesus Christ with an attitude of personal favoritism. James 2:1

          If anyone thinks himself to be religious, and yet does not  bridle his tongue but deceives his own heart, this man’s religion is worthless James 1:26

          This you know, my beloved brethren. But everyone must be quick to hear, slow to speak and slow to anger; James 1:19

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          • #20
            Why did they try to photograph one so far away instead of something closer? Like Sagittarius A-Star?

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            • #21
              Originally posted by Sparko View Post
              Why did they try to photograph one so far away instead of something closer? Like Sagittarius A-Star?
              They actually did Image Sagittarius A (the milky way's central black hole), but our galaxy's heart is not active like m87, and so the image looks a bit more like a half-circle than the nice silhouette from m87.

              Black holes are interesting in that since their diameter is determined by the escape velocity being c (the speed of light), their diameter scales linearly with their mass, not with the square-root of their mass like most normal objects. So The black hole in the center of our galaxy, while only 26,000 ly away, is, at 4.5 million solar masses, about 10 time the diameter of the sun. OTOH, the 6.5 billion solar mass black hole in the center of m87 is 1500 times larger, about the size of our entire solar system. So it turns out there really isn't as much difference in their apparent size (about 50uarcsecs for sagitarius A and about 40uarcsec for the m87 black hole) as one might expect, because m87, though 2000 times farther away, is about 1500 times bigger.*


              Jim

              *lots of rounding with the numbers ... just concerned about orders of magnitude in this case.
              Last edited by oxmixmudd; 04-12-2019, 01:15 PM.
              My brethren, do not hold your faith in our glorious Lord Jesus Christ with an attitude of personal favoritism. James 2:1

              If anyone thinks himself to be religious, and yet does not  bridle his tongue but deceives his own heart, this man’s religion is worthless James 1:26

              This you know, my beloved brethren. But everyone must be quick to hear, slow to speak and slow to anger; James 1:19

              Comment


              • #22
                Originally posted by oxmixmudd View Post
                They actually did Image Sagittarius A (the milky way's central black hole), but our galaxy's heart is not active like m87, and so the image looks a bit more like a half-circle than the nice silhouette from m87.

                Black holes are interesting in that since their diameter is determined by the escape velocity being c (the speed of light), their diameter scales linearly with their mass, not with the square-root of their mass like most normal objects. So The black hole in the center of our galaxy, while only 26,000 ly away, is, at 4.5 million solar masses, about 10 time the diameter of the sun. OTOH, the 6.5 billion solar mass black hole in the center of m87 is 1500 times larger, about the size of our entire solar system. So it turns out there really isn't as much difference in their apparent size (about 50uarcsecs for sagitarius A and about 40uarcsec for the m87 black hole) as one might expect, because m87, though 1500 times bigger, is about 2000 times farther away.


                Jim
                Yeah I always wondered how you could have a "bigger" black hole if they were all singularities with no size at all. The event horizon would change with the mass but the size of the singularity would always be at zero. Which is just weird. Where IS the mass then?

                Comment


                • #23
                  Originally posted by Sparko View Post
                  Yeah I always wondered how you could have a "bigger" black hole if they were all singularities with no size at all. The event horizon would change with the mass but the size of the singularity would always be at zero. Which is just weird. Where IS the mass then?
                  Yeah - the answer there is that inside the event horizon things like volume and size don't really have the same kind of meaning they do outside it. I know Hawking was involved with various debates about what goes on in there, giving rise to hawking radiation, bets about whether or not information entering a black hole was really lost to this universe etc. The bottom line is that no-one really knows what goes on in there because, since there is a singularity at the center, the math breaks down - doesn't yield a solution. So really the only meaningful measure of a black hole's 'size' on our side of the event horizon is, in fact, the diameter/volume of the event horizon and its mass.


                  Jim
                  Last edited by oxmixmudd; 04-12-2019, 01:23 PM.
                  My brethren, do not hold your faith in our glorious Lord Jesus Christ with an attitude of personal favoritism. James 2:1

                  If anyone thinks himself to be religious, and yet does not  bridle his tongue but deceives his own heart, this man’s religion is worthless James 1:26

                  This you know, my beloved brethren. But everyone must be quick to hear, slow to speak and slow to anger; James 1:19

                  Comment


                  • #24
                    This "telescope" is going to grant us a better look at the might and majesty of God's creation. If nothing else that is way cool.

                    I'm always still in trouble again

                    "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
                    "Overall I would rate the withdrawal from Afghanistan as by far the best thing Biden's done" --Starlight
                    "Of course, human life begins at fertilization that’s not the argument." --Tassman

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                    • #25
                      Originally posted by oxmixmudd View Post
                      They actually did Image Sagittarius A (the milky way's central black hole), but our galaxy's heart is not active like m87, and so the image looks a bit more like a half-circle than the nice silhouette from m87.

                      Black holes are interesting in that since their diameter is determined by the escape velocity being c (the speed of light), their diameter scales linearly with their mass, not with the square-root of their mass like most normal objects. So The black hole in the center of our galaxy, while only 26,000 ly away, is, at 4.5 million solar masses, about 10 time the diameter of the sun. OTOH, the 6.5 billion solar mass black hole in the center of m87 is 1500 times larger, about the size of our entire solar system. So it turns out there really isn't as much difference in their apparent size (about 50uarcsecs for sagitarius A and about 40uarcsec for the m87 black hole) as one might expect, because m87, though 2000 times farther away, is about 1500 times bigger.*


                      Jim

                      *lots of rounding with the numbers ... just concerned about orders of magnitude in this case.
                      I guess not many are reading. The Diameter of an object scales with the cube root of the mass for most objects. I was thinking of the escape velocity which normally scales with the square root of the radius (or diameter)

                      Jim
                      My brethren, do not hold your faith in our glorious Lord Jesus Christ with an attitude of personal favoritism. James 2:1

                      If anyone thinks himself to be religious, and yet does not  bridle his tongue but deceives his own heart, this man’s religion is worthless James 1:26

                      This you know, my beloved brethren. But everyone must be quick to hear, slow to speak and slow to anger; James 1:19

                      Comment


                      • #26
                        I was introduced to the idea of black holes in a book by Alan Dean Foster, "The End of the Matter". I don't care much for his style but the book's plot around the black hole was interesting.

                        I don't really know WHY black holes would exist but they sound interesting.
                        Watch your links! http://www.theologyweb.com/campus/fa...corumetiquette

                        Comment


                        • #27
                          Originally posted by DesertBerean View Post
                          I don't really know WHY black holes would exist but they sound interesting.
                          Gravity
                          Glendower: I can call spirits from the vasty deep.
                          Hotspur: Why, so can I, or so can any man;
                          But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

                          go with the flow the river knows . . .

                          Frank

                          I do not know, therefore everything is in pencil.

                          Comment


                          • #28
                            Originally posted by DesertBerean View Post
                            I don't really know WHY black holes would exist but they sound interesting.
                            The "why" question is easy: To proclaim God's glory.

                            Now as to the "how" question, I don't have the requisite scientific knowledge to answer that question.

                            Comment


                            • #29
                              Originally posted by DesertBerean View Post
                              I was introduced to the idea of black holes in a book by Alan Dean Foster, "The End of the Matter". I don't care much for his style but the book's plot around the black hole was interesting.

                              I don't really know WHY black holes would exist but they sound interesting.
                              I guess in one sense they exist because nothing can go faster than light, and because of how gravity works. The more mass you can get into a certain volume of space, the stronger the gravity. The stronger the gravity, the faster you have to be moving to get away from the thing itself, and the faster you have to move to stay in orbit. So basically, if you can pack enough mass into a small enough space, you have to be able to go faster than light to get away or to orbit. And since nothing can go faster than light, all you can do is fall in. And that goes for light itself. Hence 'black hole'.

                              It turns out that when a big enough star goes supernova it is indeed possible to get enough mass into that small a space, and once that happens, there is no way to undo it, at least not in the lifetime of our universe so far.

                              Galaxies all seem to have at their cores really big black holes. Though we dont yet know which came first, the black hole or the galaxy.


                              Jim
                              Last edited by oxmixmudd; 04-13-2019, 01:16 PM.
                              My brethren, do not hold your faith in our glorious Lord Jesus Christ with an attitude of personal favoritism. James 2:1

                              If anyone thinks himself to be religious, and yet does not  bridle his tongue but deceives his own heart, this man’s religion is worthless James 1:26

                              This you know, my beloved brethren. But everyone must be quick to hear, slow to speak and slow to anger; James 1:19

                              Comment


                              • #30
                                Originally posted by oxmixmudd View Post
                                I guess in one sense they exist because nothing can go faster than light, and because of how gravity works. The more mass you can get into a certain volume of space, the stronger the gravity. The stronger the gravity, the faster you have to be moving to get away from the thing itself, and the faster you have to move to stay in orbit. So basically, if you can pack enough mass into a small enough space, you have to be able to go faster than light to get away or to orbit. And since nothing can go faster than light, all you can do is fall in. And that goes for light itself. Hence 'black hole'.

                                It turns out that when a big enough star goes supernova it is indeed possible to get enough mass into that small a space, and once that happens, there is no way to undo it, at least not in the lifetime of our universe so far.

                                Galaxies all seem to have at their cores really big black holes. Though we dont yet know which came first, the black hole or the galaxy.


                                Jim
                                Here's another question I have. How can a black hole actually swallow anything from the outside? If time slows down as you approach the singularity and basically stops at the event horizon (the speed of light), then it would basically take an eternity for anything to actually fall into black hole wouldn't it?

                                Comment

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