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Birth of a Supercluster

Long-time Centauri Dreams readers know that I love things that challenge our sense of scale, the kind of comparison that, for example, tells us that if we traveled the distance from the Earth to the Sun, we would have to repeat that distance 268,770 times just to reach the nearest star. It’s much simpler, of course, to say that Proxima Centauri is 4.25 light years from us, but it’s the relating of distances to things that are closer to us that gets across scale, especially for those who are just beginning their astronomical explorations. And I have to admit that the scales involved in going interstellar still pull me up short at times when I ponder them.

So how about this for scale: We have somewhere between 200 billion and 300 billion stars in our galaxy (the number is flexible enough that you’ll see a wide range in the literature). Relate that to the Local Group, the gathering of galaxies that includes both the Milky Way and M31, the Andromeda Galaxy. These are the two most massive members of the Local Group, but depending on how we count dwarf galaxies, it contains more than 30 members spread out over a diameter of 10 million light years. Both the Milky Way and M31 have their own dwarf galaxies.

Then consider the concept of a ‘supercluster,’ which contains galaxy groups within it. Thus the Milky Way is considered part of both the Local Group as well as the Laniakea Supercluster, which is itself home to approximately 100,000 galaxies and subsumes the Virgo Supercluster. The Laniakea Supercluster emerged in the literature in 2014 in a paper examining the relative velocity of galaxies. Laniakea is a Hawaiian word meaning ‘immense heaven.’ R. Brent Tully (University of Hawaii at Manoa) and team identified this structure some 520 million light years in diameter, containing 100,000 galaxies, with a mass of one hundred million billion Suns.

Now a team of astronomers working with data from the European Southern Observatory’s Very Large Telescope (VLT) using its VIMOS (VIsible Multi-Object Spectrograph) instrument has identified a proto-supercluster that formed in the early universe 2.3 billion years after the Big Bang (i.e., its redshift of 2.45 means that astronomers observe it as it was 2.3 billion years after the Big Bang). ESO is describing the discovery, which they have nicknamed Hyperion, as the most massive structure yet found so early in the formation of the Universe.

“This is the first time that such a large structure has been identified at such a high redshift, just over 2 billion years after the Big Bang,” explained the first author of the discovery paper, Olga Cucciati. “Normally these kinds of structures are known at lower redshifts, which means when the Universe has had much more time to evolve and construct such huge things. It was a surprise to see something this evolved when the Universe was relatively young!”

Image: An international team of astronomers using the VIMOS instrument of ESO’s Very Large Telescope have uncovered a titanic structure in the early Universe. This galaxy proto-supercluster — which they nickname Hyperion — was unveiled by new measurements and a complex examination of archive data. This is the largest and most massive structure yet found at such a remote time and distance — merely 2 billion years after the Big Bang. Credit: ESO/Luis Calçada and Olga Cucciati.

Hyperion emerged in the analysis of a field in the constellation Sextans carried out by researchers in the VIMOS Ultra-deep Survey, which has been creating a 3D map of the distribution of over 10,000 galaxies. Hyperion contains seven high-density regions connected by thin ‘filaments’ of galaxies. The average supercluster, says Brian Lemaux (University of California, Davis), an astronomer and co-leader of the team behind this result, shows more concentrated distribution of mass and clear structure. “But in Hyperion,” Lemaux adds, “the mass is distributed much more uniformly in a series of connected blobs, populated by loose associations of galaxies.”

The mass distribution makes sense when you consider that nearby superclusters have had billions of years to create the observed clumping into denser regions with more defined structure. We might expect Hyperion to evolve into something more like the Virgo Supercluster, and studying it should provide insights into how galactic superclusters evolve. It offers a rare glimpse into the early era of supercluster formation, and another signpost of immensity.

What’s ahead for the study of Hyperion? Calling it a “unique possibility to study a rich supercluster in formation 11 billion years ago,” the paper adds this:

This impressive structure deserves a more detailed analysis. On the one hand, it would be interesting to compare its mass and volume with similar findings in simulations, because the relative abundance of superclusters could be used to probe deviations from the predictions of the standard ΛCDM model [Lambda cold dark matter, a model that includes a cosmological constant, dark energy and cold dark matter]. On the other hand, it is crucial to obtain a more complete census of the galaxies residing in the proto-supercluster and its surroundings. With this new data, it would be possible to study the co-evolution of galaxies and the environment in which they reside, at an epoch (z ∼ 2 − 2.5) when galaxies are peaking in their star-formation activity.

The Hyperion findings are being compared to the results of the Observations of Redshift Evolution in Large Scale Environments (ORELSE) survey, led by Lori Lubin (UC-Davis), who was on the team that discovered Hyperion. ORELSE studies superclusters closer to Earth using data from the W.M. Keck Observatory in Hawaii. The next step will be to map out Hyperion in greater detail.

The paper is Cucciati, et al., “The progeny of a Cosmic Titan: a massive multi-component proto-supercluster in formation at z=2.45 in VUDS,” accepted at Astronomy & Astrophysics. Preprint.


Comments on this entry are closed.

  • Adam Byrne October 22, 2018, 14:19

    I rather like this video, although I’m not sure how accurate it is over all:


  • Thomas Goodey October 22, 2018, 14:39

    You say “And I have to admit that the scales involved in going interstellar still pull me up short at times when I ponder them.”

    Robert Heinlein’s take on this in ‘Starman Jones’ was, as nearly as I remember it, “The distances between stars were so immense, it was obvious (in retrospect) that there must be anomalies.”

  • john walker October 22, 2018, 15:22

    Here’s a perspectival eye opener for your amusement, one which I didn’t believe until I calculated it myself.

    If all viruses on the Earth were placed side by side the length of the chain would be very long. How long?
    I simplified the equation by assuming all viruses had the width of an adeno virus or 50nm.
    My initial “feeling” was that a chain with 50nm links stretched 200 million light years would require more substance than the entire Earth. A good example of the unreliablity of feeling on scales way beyond our immediate sensory realm.

    • Alex Tolley October 22, 2018, 18:35

      I once calculated that all the DNA in a human’s cells, if stretched out might reach to Neptune, more or less. You might want to try that calculation on a virus genome and repeat your calculation.

      • john walker October 24, 2018, 17:50

        That is amazing.

  • Marc Millis October 22, 2018, 16:57

    A free phone app, “Exoplanet,” lets you zoom around our galaxy from all angles and distances. By interacting with that for a bit, the scale of things gets a bit easier to grasp. As the title suggests, it has a current listing of all the observed exoplanets.
    In public lectures, I’ve also used ‘time’ to compare distances. For example, at light speed, the distance between Earth and our sun is around 8 minutes – a short conversation, while the distance to our nearest stars is well over 4 years – like getting a college degree. Grasping the difference between a short conversation and getting a college degree helps convey the scale for me. And lastly, I enjoy the phrase, “Space is so astronomically large that it makes lightspeed seem slow.”

    • Paul Gilster October 22, 2018, 20:54

      I like that ‘conversation vs. college degree’ comparison. Nice!

  • Triffin October 22, 2018, 17:45

    With regard to scales ..
    Here’s one of several “powers of 10” videos ..
    Cosmic Eye ..


  • Robin Datta October 22, 2018, 18:17

    The “things that challenge our sense of scale” extend beyond the limits of what we can grok of time and space: about two generations before and after us in time and of space the distances we travel frequently enough for familiarity.

    The blending of space and time and the measure in lightspeed, while itnellectually graspable, remains quite beyond our ken. The intellectual tools used to grapple with these ideas do not make them into concepts assimilable by our hunter-gatherer minds.

  • wdk October 22, 2018, 22:10

    Not that I’m a fan of rorschach tests per se, but these articles have got to be the best game of rorschach tests around. Especially since the images can be discussed or brain-stormed.

    Since the presentation started out with the local group of galaxies measuring about ten million light years across and home to about 30 galaxies – and then we rolled back to a structure that contained 100,000 galaxies to represent a super cluster, then I guess the dimensions of such a structure exceeds 100 million light years. Now if Hyperion ( our rorschach test) is taking on super-cluster characteristics over the same span at time Big Bang plus 2.3 billion years, there must have been some very busy wall paper hangers at work back in those days. Or else the ingredients for the cluster must been squirting out of the bottle in a more primitive form an eon earlier. I take it that the haze in the image is the emerging super cluster and the points of light are foreground stars or galaxies. So the nature of the illumination of the haze is probably an unfolding story? For example, the populations of stars, dust and even spirals within galaxies could be different than present day? Do we have much prospect near term of getting much that specific? Webb Space Telescope or something else?

    Wonder what they are doing over there now? Staring back at our emerging super cluster?

  • AlexT October 23, 2018, 4:38

    Your quote: “…beyond our ken… our hunter-gatherer minds.”
    I suppose that it will more correctly to replace in your text the word “our” by word “my”…
    I am sure human being cognition is very idividual.
    So – if someone can or cannot imagine something somehow , does not mean automatically that all human beings can or cannot do that same manner…

    • AlexT October 23, 2018, 4:40

      Sorry, placed my text in wrong place – my this notes are addressed to Robin Datta comment.

  • ljk October 23, 2018, 9:15

    If you want a more “grounded” scale comparison (I cannot stand the phrase “down to Earth”), try this: If the Sol system were shrunk in scale to one mile from Sol to Pluto and located in the middle of New York state, the Alpha Centauri system would be located in Hawaii…


    I also like this visual image of cosmic scale: If you shrunk the Sol system small enough so that our whole planetary neighborhood (sans the comet belts) could fit in the palm of your hand, the Milky Way galaxy would still be the size of the North American continent.

  • ljk October 23, 2018, 11:36

    Two relevant quotes from The Hitch-Hiker’s Guide to the Galaxy by Douglas Adams:

    “Space is big. You just won’t believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it’s a long way down the road to the chemist’s, but that’s just peanuts to space.”


    “It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. However, not every one of them is inhabited. Therefore, there must be a finite number of inhabited worlds. Any finite number divided by infinity is as near to nothing as makes no odds, so the average population of all the planets in the Universe can be said to be zero. From this it follows that the population of the whole Universe is also zero, and that any people you may meet from time to time are merely the products of a deranged imagination.”

  • ljk October 23, 2018, 12:23

    It turns out if we – or just one of us, actually – is a Boltzmann Brain, then none of these vast distances may matter:


  • Geoffrey Hillend October 23, 2018, 16:15

    Yes, the James Web Space telescope will allow us to get more specific in the target date 2021 or hopefully a little earlier.

  • Michael C. Fidler October 25, 2018, 9:42

    Well, here is something that may help us deal with the scale of the universe…

    Next Generation Telescopes Could Use “Teleportation” to Take Better Images.
    “Quantum Assisted Scope for 10,000 kilometer optical scope.”


    Quantum-Assisted Telescope Arrays.

    “Quantum networks provide a platform for astronomical interferometers capable of imaging faint stellar objects. In a recent work [arXiv:1809.01659], we presented a protocol that circumvents transmission losses with efficient use of quantum resources and modest quantum memories. Here, we analyze a number of extensions to that scheme. We show that it can be operated as a truly broadband interferometer and generalized to multiple sites in the array. We also analyze how imaging based on the quantum Fourier transform provides improved signal-to-noise ratio compared to classical processing. Finally, we discuss physical realizations including photon detection-based quantum state transfer.”


    Nonlocal Optical Interferometry with Quantum Networks.

    “We propose a method for optical interferometry in telescope arrays assisted by quantum networks. In our approach, the quantum state of incoming photons along with an arrival time index is stored in a binary qubit code at each receiver. Nonlocal retrieval of the quantum state via entanglement-assisted parity checks at the expected photon arrival rate allows for direct extraction of phase difference, effectively circumventing transmission losses between nodes. Compared to prior proposals, our scheme, based on efficient quantum data compression, offers an exponential decrease in required entanglement bandwidth. Experimental implementation is then feasible with near-term technology, enabling optical imaging of astronomical objects akin to well-established radio interferometers and pushing resolution beyond what is practically achievable classically.”



    The last image shows in detail how this could be done for even a ground based telescope arrays! So just maybe if luck holds out for this, we may be able to see those canals on some distant exoplanet!!!!

    I’m no Quantum mechanic but my quantum memory has a hunch that a quantum time crystal could hold the entanglement so that optical interferometry in telescope arrays could be combined. Thus over time the angle would stretch to billions of miles, but in only one direction, or is there some way to…