Hubble Spots a Curious Spiral


Nov. 15, 2019

Hubble Spots a Curious Spiral

Hubble image of NGC 772

The universe is simply so vast that it can be difficult to maintain a sense of scale. Many galaxies we see through telescopes such as the NASA/ESA Hubble Space Telescope, the source of this beautiful image, look relatively similar: spiraling arms, a glowing center, and a mixture of bright specks of star formation and dark ripples of cosmic dust weaving throughout.

This galaxy, a spiral galaxy named NGC 772, is no exception. It actually has much in common with our home galaxy, the Milky Way. Each boasts a few satellite galaxies, small galaxies that closely orbit and are gravitationally bound to their parent galaxies. One of NGC 772’s spiral arms has been distorted and disrupted by one of these satellites (NGC 770 — not visible in the image here), leaving it elongated and asymmetrical.

However, the two are also different in a few key ways. For one, NGC 772 is both a peculiar and an unbarred spiral galaxy; respectively, this means that it is somewhat odd in size, shape or composition, and that it lacks a central feature known as a bar, which we see in many galaxies throughout the cosmos — including the Milky Way. These bars are built of gas and stars, and are thought to funnel and transport material through the galactic core, possibly fueling and igniting various processes such as star formation.

Text credit: ESA (European Space Agency)
Image credit: ESA/Hubble & NASA, A. Seth et al.

Last Updated: Nov. 15, 2019

Editor: Isabelle Yan

63 thoughts on “Hubble Spots a Curious Spiral

    • That comment reminded me of an Aunt and Uncle.
      They dragged their family, a girl and a son on a family trip to Mexico back in the 1970s.

      In every town, or to be exact, everywhere they saw a bar, they stopped and took a family photo.

      While their stories were funny, their photographs were picture after picture of a tired bedraggled family standing in front of adobe walls. When the picture included a corner of the bar’s entrance,they could name the town and bar. Otherwise, no.

      If one was careful, it was possible to roughly line up the pictures by how bored and disgusted the kids looked. At each succeeding town, the kids looked more and more tired, bored and tired. Especially since my Aunt and Uncle each had to visit the bar’s inside, kids wait outside.
      My cousins wouldn’t even discuss the trip.

    • ATheoK November 16, 2019 at 12:48 pm

      That comment reminded me of an Aunt and Uncle.

      They dragged their family, a girl and a son on a family trip to Mexico back in the 1970s.

      In every town, or to be exact, everywhere they saw a bar, they stopped and took a family photo.

      [] At each succeeding town, the kids looked more and more tired, bored and tired. Especially since my Aunt and Uncle each had to visit the bar’s inside, kids wait outside.

      My cousins wouldn’t even discuss the trip.


      Till today you don’t know why Aunt and Uncle each had to visit the bar’s inside,

      and kids had to stay outside.

    • Could it be “My cousins wouldn’t even discuss the trip”

      because Aunt and Uncle made the photos before entering the bar and unobtrusively left the kids outside with the camera.

      Inside the bar they could have said “there’s proof we’re here. There’s photos of us entering the bar!”

    • Leaves to say that since there is no proof of man-made global warming the null hypothesis is “there is no such thing as man-made global warming.”

  1. There is a faint but visible trail of dust spiraling in toward the center of NGC772, which is quite bright.

    Maybe it’s still too young to have hit the bars just yet. Or maybe it’s just “different”.

    Nice photo!

  2. Interestingly, there is a less bright spot in the center of the galaxy where you you would expect the resident black hole to be. Probably nothing, but interesting none the less.

  3. The Universe is full of mysteries beyond capacity of a single human mind to comprehend. One day the AI may be able to assimilate and resolve the enigma.
    Even closer at home, our own star has its secrets, as I just found that in the last 20 months since the solar activity has entered
    current minimum is month by month a near carbon copy of the last one
    as you can see here

      • I would agree but also disagree to an extent. A single human mind can imagine the abstract concepts and the algorithms to collect and analyze data. Usually many human minds collaborate either contemporaneously or sequentially across generations to refine the abstract concepts. There are also meta-abstractions that can be imagined for how to draw conclusions from data to select or combine hypotheses, which allow for the appearance of abstract thinking by a machine. These are just rigid, rigorous applications of logic, even if the algorithms mimic human fuzzy logic. So ultimately any AI outcome is the work of its programming team.

        The sheer number of objects in the universe exceeds the cells in the human brain, and the finite lifetime and number of living individuals makes it impossible for a single individual or even the whole society to process all the data.

        AI is nothing more than artificially applying algorithms to test massive amounts of data.

        • AI is a misnomer. It should be SI: Simulated Intelligence, which will probably be able to perform wiggle-matching* with the best of us.

          * the creation of algorithms that cause comparative data peaks and troughs to align…except when they don’t.

    • With AI today a massive lookup table generated by self-programming (sort of) algorithms based on scanning massive quantities of test data, how do you believe AI will correctly identify anything it hasn’t already seen?

      • The AI is in its infancy, I would not assume that its future capacity and ability can be assessed to any degree of accuracy.

        • I’ve been hearing AI is in it’s infancy since the 1980s.

          Two relatives of mine studied AI for their degrees. Both work in other computer fields now.

          William Briggs has it correct.
          For now and the foreseeable future, AI is reliant upon program code; i.e. stylized human language for instructing machines.
          AI is utterly unable to identify something new that has never been described.
          “It does not compute” is a program breaker for AI.

          Developing programs that must process multiple data input streams simultaneously is extremely difficult. Machines are all too apt at holding one line of programming in stasis when another line of coding has priority or demands more CPU time.

          Allowing programs to “self program” are pathways to infinite program size.
          Leaving AI program future somewhere beyond the coding paradigm.

    • Till today there is no “theory of everything”.

      So the null hypothesis IS there is no “theory of everything”.


      “A theory of everything (TOE) is a hypothetical framework explaining all known physical phenomena in the universe. Researchers have searched for such a model ever since the development of quantum mechanics and Albert Einstein’s theory of relativity in the early 20th century.Aug 29, 2019”

  4. My questions are:

    1. what is the estimated diameter of the central “core” in the photograph?

    2. what is the composition of the central “core”?

    3. is the swirling particulate surrounding the central “core” being gravitationally sucked into the rotating core?

    4. or is the swirling particulate surrounding the central “core” being centrifugally extruded from the rotating core?

      • Well now I wasa curious about which direction (in or out) the surrounding “swirling particulate” was being transported.

        Given the fact that Astronomers claim that monster Black Holes at centers of galaxies “suck in” all particulate surrounding them ……. and given the fact that the picture denotes a monster White Holes at the center of the pictured galaxy …… I had to assume that monster White Holes at centers of galaxies surely must be “blowing out” all the “swirling particulate” surrounding them.

        Or should I just be assuming that said …… monster White Hole at the center of the pictured galaxy …….. will eventually become a monster Black Hole at the center of said galaxy?

        In other words, ……. is the pictured galaxy currently a galactic star (sun) birther ….. or a galactic star (sun) consumer?

        Curious minds would like to know.

    • Clearly ze identifies as an elliptical galaxy because ze never developed a bar and hir satellite was overbearing, but ze still speaks with a deep voice and has broad shoulders.

  5. I always come back to when reading about theses things that the only thing that makes sense is that Black Holes are Galaxy Regenerators. There are not galaxies without black holes, they are intrinsic to their nature.

    • AFAIK, M33 (the Triangulum Galaxy), the 3rd largest member of our Local group, has not yet had a center SM black hole detected. None (supermassive) in the small local-group satellite galaxies either, tho they certainly contain solar-mass black holes.

  6. How do we know what the Milky Way would look like from this galaxy? (Asking for a friend. I wouldn’t be so “uninitiated”.)

    • Starfleet has sent hundreds of probes out at warp speeds greater than humans can tolerate so that we have images of the Milky Way from the perspective of other galaxies. Haven’t you, er hasn’t your friend heard about that?

      Even before that, I suppose that we could have created 3D models based on a composite of galaxies that we can observe from various orientations and positions and relative motion of stars we can observe, then check to see what the sky would look like from various points in that model. The model that best simulates our actual sky should be close to our own galaxy.

    • Our solar system is not orbiting the Milky Way Galaxy exactly on the galaxy centerline.

      That is; our solar system is enough off center that astronomers can give a good guess to how our Milky Way looks.

      One of their recent findings/possibilities is that the Milky Way Galaxy has two spiral arms, not four.

      Not to worry, Andromeda galaxy will collide with the Milky Way galaxy in 4-6 billion years and we’ll get a new galactic neighborhood; ejected into space or crash into a star.

      • Or, there’s so much space between everything (we can’t even see the galactic mass of our own galaxy unless there is no light pollution on a clear night), that we might not even notice.

        • Visualize two marching bands on a field marching through each other, yet no one collides, not even the Sousaphone players.

          The interstellar space is that vast.

    • “How do we know what the Milky Way would look like from this galaxy?”

      I’m with you. The solar system ‘bobble’ is not extreme enough to see what the MW looks like so how do we know it is a barred spiral? I’ve read a lot of papers and articles explaining apparent movement of our stars etc. but I haven’t seen anything other than assertions that the MW is barred.

      Not far from us, the Sag cluster is being stripped by the MW – given it is impacting (if I can use that word, given the actual process) at ~60° to the plane of the galaxy, that the solar system ecliptic is at ~60° to that plane and that the aforementioned ‘bobble’ could be the result of an elastic ‘collision’ with (say) Sirius, which just happens to have an odd apparent motion with respect to the Sun – and we may be from the Sag cluster rather than the MW.

      Local chemicals and star composition notwithstanding. i.e. we may not be the only star to be captured on this orbit of Sag through MW.

      So I’d be interested to see the effects of the interaction between 772 & 770. It could give us an idea of just what is going on in our region, a region to which we may be too lose to envisage accurately and thus think (maybe) that this is how the rest of the MW disk looks.

  7. It would be interesting if WUWT would give us a few thoughts or musings by astronomers as to why the galaxy appears like this.

    • “…few thoughts or musings … as to why the galaxy appears like this.”

      According to either Newtonian or Einsteinian gravity, they shouldn’t appear like that as their outer spiral arms are traveling too fast. Astronomers had to invent Dark Matter to explain this discrepancy. This explanation always bothered me as it requires an as yet unknown type of mater distributed in a very specific manner within the galaxy that can not be detected in any way except though its gravitational influence. A theory like Entropic Gravity seems to me to be a simpler explanation of the problem though it too has its drawbacks.

      • First of all We need more information about the image: is it visible light spectrum, radio spectrum,
        x-ray spectrum or a composite of all these.

        What strikes me is the appearance of filamentary structures. This leads me to believe it is a composite image incorporating radio imaging and x-ray imaging with visible light.

        A hundred years ago Einstein convinced the scientific world that the ether did not exist, that interstellar space was a vacuum and the only motive force active at stellar distances was gravity.

        Einstein died in 1955. Sputnik was launched in 1957, ushering in the space age and allowing us to explore the previously inaccessible reaches of ‘space’. What was discovered was that the ‘vacuum’ of space was in fact populated with diffuse electrically charged plasma.

        Cosmology needs to incorporate electromagnetic forces into the gravitational model of the universe.
        The electrical force is 10^39 times stronger than the gravitational force. Plasma IS the missing dark matter. Call upon the work of Faraday, Maxwell, Heavyside, and Lorentz. Plasma (in the lab) produces filamentary structures. Plasma currents produce radio emissions. Electromagnetic fields accelerate electrons. Molecules struck by accelerated electrons emit x-rays. (This is how the dentist’s x-ray machine works.)

        The advent of radio telescopes and x-ray telescopes unveiled a universe of complexity never before seen. I think Einstein today would recognize the need to expand the horizons of our thinking. He was, after all, a very humble man.

        • Oliver Heaviside (and Heinrich Hertz) pretty much shredded Maxwell’s work and made his 4D equations (Quaternions) into vector equations – in the process we lost 2 forces, electrostatic and electrogravitic.

          Einstein’s universe wouldn’t exist in Maxwell’s original schema – that his work was brilliant is shown by how far we’ve come even with the truncated work on which we’ve based physics.

          Reg Cahill and a few others also show that Michelson-Morley did NOT have a null result and in fact showed an aether effect. (aether = active ether, i.e. not the dead mechanistic one we now have)

          Einstein’s universe does not work with an aether.

          Dark Matter (DM) is not the only magic required to make the universe follow the Big Bang scenario. Inflation was magicked up because the Big Bang literally CANNOT produce the Universe we see in the time given or with the large scale structures we see. Inflation is literally defined as the force needed to make the universe match the mathematics by appearing, stretching in defiance of the SoL, then going away again.

          Halton Arp got a mention… Dark Energy is more magic, a conjuring to explain why RedShift (RS) shows in all objects far enough away from us – magic that it somehow doesn’t ALSO work for closer objects. The idea that RS = Velocity is unproven but ubiquitous in cosmology, and yet Arp and a few others have pointed out high RS objects with physical and/or energetic connections to low RS objects.

          As we add in the electric side of things, we should not ignore the magnetic side. Many of the electric phenomena we can SEE out in space show strongly they are constrained by magnetic fields and our climate is being shown to be mostly affected by magnetic effects in the Sun.

          • Dark Matter (DM) is not the only magic required to make the universe follow the Big Bang scenario.

            Magic is correct, cause ole dummy me figured that …… with so much DM out there, exerting its gravitational attraction on visible objects ….. then the Periodic Comets (Haley’s) should have been diverted from their defined orbits eons ago.

            Shouldn’t the DM attraction be far greater than say planet Jupiter’s attraction?

      • RicDre – November 16, 2019 at 8:09 am

        “…few thoughts or musings … as to why the galaxy appears like this.”

        According to either Newtonian or Einsteinian gravity, they shouldn’t appear like that as their outer spiral arms are traveling too fast.

        Shouldn’t the “outer spiral arms” still be travelling at the same rotational speed as the inner core?

        What’s to slow them down?

        The “outer spiral arms” are receding away from (increasing diameter) the inner core, ….. thus their orbital distance around the inner core keeps increasing …… therefore, me thinks, that causes the appearance that their orbital speed is decreasing.

        But whatta I know, …. I’m not a Degreed astronomer.

  8. There was a great unsolved mystery about spiral galaxies for 50 years or more: how could the spirals stretch across the galaxies in an unbroken fashion when the inside of the galaxy is spinning around faster than the outside? Often a galaxy is old enough to have made 20 or more revolutions outside and many more than that inside. Why wouldn’t the spirals wind up? Great physicists and astronomers tried and failed to answer the question. Finally a fluid mechanics guy from MIT (CC Lin) treated the problem not as a bunch of particles (stars) controlled by gravity but as a fluid. He found that a “density wave” could maintain a pattern like what we see, despite the differential revolution. The reason we see the spirals is because the peak of the density wave condenses existing dust and gas and forms the bright blue stars that outline the spirals. After a time they fade and the density wave advances and forces new stars to be born a littler further on, maintaining the spiral shape.

    • Wouldn’t a density wave operate in a medium? i.e. not a vacuum?

      Would a magnetic or electric field support a density wave or does it have to be matter of some kind?

  9. Very picturesque w/its tightly-wound dust lanes. Similar to the Milky Way in that it has a relatively small central bulge (with an accompanying rather small supermassive black-hole???). It lacks the bar that characterizes our galaxy tho.

  10. I wonder if the immutable laws of physics apply there and if it is warming secondary to a minute concentration of CO2?

  11. There are an amazing number of blue stars in that picture.

    Meaning that galaxy is new or recently refreshed.

  12. On one of the planets orbiting one of the 100 million or so stars in the outer arms of galaxy NGC 772, there is a group of intelligent life forms looking at a photo from a newly launched orbiting telescope with a resolution that could not have been dreamed of before they started building rockets and sending stuff outside their atmosphere. They are looking at a photo of the Milky Way. One of them is communicating to the others through a delocalized digital medium that links them all, and that they call (for want of a better word) “the internet” and he/she/it is saying “Holy sh*t, look at that, I wonder if there are intelligent life forms there”

  13. I thought, perhaps, that the “peculiar” aspect of the galaxy might be it’s rotational direction. But its declination is almost exactly 19 degrees north, which puts it in the galactic northern hemisphere – and it’s rotating counterclockwise, just the way any good cyclone in the NH would.

  14. MarkMcD November 16, 2019 at 3:40 pm

    “How do we know what the Milky Way would look like from this galaxy?”

    I’m with you. The solar system ‘bobble’ is not extreme enough to see what the MW looks like so how do we know it is a barred spiral?

    What is the center of our Milky Way galaxy?

    At its center, surrounded by 200-400 billion stars and undetectable to the human eye and by direct measurements, lies a supermassive black hole called Sagittarius A*, or Sgr A* for short. The Milky Way has the shape of a spiral and rotates around its center, with long curling arms surrounding a slightly bulging disk.Jul 21, 2010

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