Posts Tagged ‘galaxies’

AT THE BEGINNING OF TIME; what the James Webb telescope might see

July 21, 2022

Congratulations to the whole James Webb team. Against all the odds they have built us a cathedral in Space as awesome as Santa Sofia, and a window through which we can potentially look almost all the way back to the beginning of Time. What might we see? What should we be looking for?

I’m waiting as eagerly as anyone because I have been involved in this stuff going right back to 1977 as a key member of three Hubble Space Telescope teams, including the one that built the camera still going strong up there now. And in this post I want to pass on some words of both encouragement and warning. Be ready for surprises!

Before they design a single lens or circuit Space-camera teams must look deeply into the kinds of science they might be doing 20 years ahead and my team asked me to look into high redshift galaxies. Knowing nothing of that subject at the time  (1977) I naturally went round to ask the real experts. They were unanimous: “Don’t bother with them because you’ll never be able to see them owing to the Tolman effect.”

I looked it all up and found that Richard Chase Tolman was a brilliant American astrophysicist who probably knew more about Relativity than Einstein. The idea that the whole universe was expanding had just been mooted in the 1930’s and Tolman tried to find a test that would prove it. And he did. Extended objects like galaxies would be dramatically dimmed by redshift in an expanding universe, so dimmed in practice as to become invisible in any decent Space camera. Imagine my shock then in 1993 when we got our first really deep Hubble image. It was plastered all over with very distant but quite distinct galaxies not dimmed in the least. That meant the universe couldn’t be expanding – not according to Tolman.

But when I tried to point this out the new self-appointed experts said; “No ; it just means that young galaxies in the distant past were intrinsically much brighter than the galaxies today – after all they were younger in the past and generating more brilliant young stars.”

That sounded vaguely plausible – but not really convincing. Why not? Because all the galaxies: irrespective of their distance had exactly the same surface-brightnesses as each other, and as the galaxies around us here today. For that to be true there just had to be far too many fortuitous coincidences. But by the time I’d measured this and worked it all out a whole

industry consisting of hundreds of newly minted ‘High redshift galaxy astronomers’ had become wedded to their fortuitous hypothesis. The idea that the universe wasn’t expanding was to them completely unthinkable. To my shame I mostly shut up and kept my council. Tolman had presumably screwed up somewhere back in the 1930s.

The Hubble Ultra Deep Field, still the deepest picture ever taken of the Universe. Notice that it is covered all over with galaxies in the far distance, but their surface brightnesses are no dimmer than those that are obviously nearer by. This is a very great puzzle ,because according to the ‘Tolman Effect’ they should be far too dim to see.

But later (2009) we sent an even more sensitive camera (WFC- 3) up to Hubble specifically to look at the higher redshift universe – and guess what – it was plastered with high surface brightness galaxies going out all way to redshift 7 – to a time when the universe was less than 1 billion years old (it’s 13 billion today).

Still the ‘experts’ weren’t shocked – and I realised they could explain everything – and in doing so – nothing. They were too wedded to their trendy hypothesis to ever question it.

But by 2010 I had officially retired which meant I could do something those experts could not. I could spend literally thousands of hours thinking about the problem of high redshifts galaxies and my colleague Huw Lang and

I eventually produced a refereed paper entitled “The Galaxy Ancestor Problem” in a prestigious astrophysical journal (see Note). We argued that the trendy picture simply couldn’t be right, and that something probably far more interesting was afoot.

Nobody read it, apart from the referee. And you can’t blame them. It contains 70 numbered equations and is hideously complex. It was much easier to ignore it than try to understand it. That’s part of a long tradition in astronomy going back 600 years: if you don’t like something, stick with the crowd and ignore it. 15th century astronomers didn’t want to believe the Earth was orbiting the Sun, and invented ridiculous ‘epicycles’ to disguise the truth from themselves – and everybody else. Only when Galileo saw with his first spyglass (1609) that Venus was crescent-shaped did they finally ‘Hesitate’. What they did though was imprison Galileo for life (1632) – because that was much easier than changing their minds.

There is a more general point here though. Explorers rarely comprehend what they have discovered at the time. Columbus never admitted that he’d run into a new continent – so far as he was concerned he’d been to Cipangue (Japan) – because that is where he’d set out to go. It took his successors, notably Amerigo Vespucci, to acknowledge that the previously unknown continent of America actually existed.

I’m not claiming that Huw and I are right, and that everybody else is wrong, I’m merely pointing out that the true interpretation of the high redshift universe, the universe Webb will soon see in unprecedented detail, may be very surprising, very surprising indeed.

Without going into any detail let’s enumerate three key puzzles:

(I) Tolman couldn’t be wrong: his physics is as sound of a bell. So, if the universe really is expanding, which seems likely, why do all the galaxies, irrespective of their redshift, appear to have the same identical surface- brightness? High redshift galaxies are no less than 4000 times brighter than they ought to be. There’s no escaping from that. 4000 times!

(II) That we can see so far means that the cosmos out there is transparent. That’s obvious. But how did it become so? Where did all the energy come from to split all the electrons in extra-Galactic space apart from their natural proton partners ? That is called ‘The Re-ionisation Problem’. There are vastly too few galaxies out back there to produce the ionising starlight needed to bust all those atoms apart and make Space transparent.

(III) Very high redshift objects, notably Quasars, have dozens, sometimes hundreds of dark lines in their spectra(see our Post ‘The Cosmic Rosetta Stone’). Those lines could only be produced by the atoms in galaxies along the lines of sight to such quasars. But there are vastly too few such visible galaxies out there to produce them.

Many people will be surprised that such egregious problems are not shouted from the roof  tops; there is almost a conspiracy to cover them up. The only comment I will make upon that is that ‘experts’ are generally reluctant to admit “We really don’t know”. Take the situation of Continental Drift. For 50 years the experts at all the ‘big’ universities pooh-poohed Alfred Wegener’s radical idea. They were only forced to eat their hats when otherwise inexplicable geomagnetic patterns turned up on the ocean floor. Perhaps the James Webb will force a similarly dramatic rethink.

During its recent briefing about Webb NASA was anxious to emphasise that “The telescope belongs to all of us”. That will only be true if we all dare to think about the new high red shift observations – when they come in. If we don’t, the ‘experts’ might cover up the truth – yet again.

NOTES: The Disney/Lang paper is at Disney M J., and Lang R.H, The galaxy ancestor problem, Mon. Not. R Astron. Soc., 326, 1733-1749 (2012). Other relevant Posts on this site are: ‘The Cosmic Rosetta Stone’; ‘How Dark is the Night?’; ‘Hidden Galaxies, Hidden Universe’. They’re under the ‘Astronomy’ Category.

BIG BANG COSMOLOGY IS WRONG

February 20, 2021

If you wanted to know what to think of some fringe activity such as Spiritualism or Water Divining I doubt one would consult a professional first. After all you know that they must be committed. But what if you wanted to evaluate Big Bang Cosmology? Once again you can’t turn to the biased professionals, although they might argue that unless you are a professional you cannot know enough about the subject to take an informed position. But of course that is a dangerous stance to adopt, and the way in which priesthoods germinate, metastasize and sometimes come to dominate the world. They become immune to criticism because they will admit none but believers as critics. They become malignant, if not necessarily malign.

So what is the wise outsider to do? I would suggest they might consult those whose business it is to know much about the arcane subject- material in question without having to become paid exponents themselves. Cosmology for instance is in practice largely extra-galactic astronomy, so why not consult an extra-galactic astronomer who doesn’t claim to be a Cosmologist? Such an astronomer will know most of the technical arguments – without having to commit to them. That is where I stand with regard to Big Bang Cosmology, or BBC. My passion lies in Galaxies, the largest discrete objects in the Universe. But as they seem to be almost as old as the Cosmos, their origin must be entangled in the early evolution of the Universe itself, so I cannot ignore Cosmology, any more than Cosmology can ignore Galaxies which, so far as we know, comprise most of everything we can actually observe. And as visible galaxies exist in hundreds of thousands of millions, and can be observed in some detail nowadays, they should tell us more about Cosmology than vice-versa. And here is the rub: in BBC galaxies shouldn’t exist. As has been known for fifty years they would have been torn apart by radiation pressure before they could even form. So a desperate fix called CDM, standing for ‘Cold Dark Matter’ was adopted to try and repair the awful hole in the story. But despite many efforts to find out what it is, no one has been able to find any trace of CDM in half a century. Umm.

And there is another stark confrontation between galaxies and Cosmology. In an expanding Universe – the core assumption of BBC – distant galaxies should be totally invisible because of the ‘Tolman Effect’, a test for Expansion, which goes back to 1930. Then we didn’t possess the the telescopes to test it, but now, in the Hubble Space Telescope, we certainly do. And what do we find? That the observed Universe fails – and fails most dramatically – as you can see for yourself. Look at the figure:

The Hubble Ultra Deep Field, the deepest image of the Universe , taken with the Hubble Space Telescope, which I helped to design. All those tiny dots are actually high redshift galaxies a long long way away. If the Universe is really expanding we shouldn’t be able to see them. But……..

You can see it’s covered all over with a rash of tiny high-redshift galaxies – which simply shouldn’t be there, not if the Universe is expanding. If it was they ought to look no less than ten thousand times dimmer than they appear to be. Surely this is something BB Cosmologists ought to acknowledge? But they don’t. It’s been known since 1993 when we first fixed the telescope’s aberrated mirror, but ever since there has been a conspiracy of silence about the matter. As a designer of the existing and earlier cameras, I was staggered when I first saw the earliest deep Hubble images because I’d been assured by Cosmologists that Hubble would never see high-redshift galaxies. Yet there they were. There they are in their hundreds and thousands.

The only precedent I can think of occurred back in 1610 when Galileo pointed his little spyglass at Venus and found it to be a brilliant crescent pointing towards the Sun. The two-thousand-year-old Geocentric picture of the Cosmos was quite wrong, All the Planets, including the Earth, must be orbiting the Sun.

But what happened? Galileo was eventually seized by the Inquisition, forced to retract, and then imprisoned for life.

We don’t have an Inquisition any more but we do have Priests of a different kind: experts whose livelihoods, reputations and ambitions enforce adherence to a certain dogma. It’s not easy when you are an elderly, respected professor of Cosmology, with several books and hundreds of peer-reviewed papers behind you, to admit that you have been wasting yours, and everybody else’s time. And if the old won’t recant, why should the young, who still have their reputations and their livings to make? There is no Inquisition it is true but there are, in a highly competitive profession, appointment and tenure committees to please, journal-referees to propitiate. Brave myths to the contrary, academic success is based above all on allegiance to the Common Book of Prayer.

I know it will be hard for outsiders to believe in such conformity, I certainly wouldn’t have believed in it myself if I hadn’t experienced it at first hand, and to some extent colluded rather shamefully in it myself. Yes I went to conferences and politely pointed out the anomalies facing us in the sky. I even published papers in elite journals like ‘Nature’ demonstrating that real galaxies couldn’t possibly have formed in the CDM manner proclaimed by cosmological theorists. But when nobody responded, shouldn’t I have bellowed and trumpeted my doubts?

Honestly I should. But two things held me back; lack of self -confidence for one. Cosmology is a huge and complex subject mired in the hardest Mathematics and Physics – and perhaps I’d missed something – which the experts had not? Then again it wasn’t my real love. If I acquired a reputation as a madman I wouldn’t get the observing time on top telescopes I absolutely needed to do my Galaxy research. Many of us subscribe to popular myths, knowing them to be untrue. One well-known colleague told me that when he is applying for observing time he always alludes to CDM, which he knows to be diseased, because he’s found that if does not, he won’t get the time. And so CDM, a central dogma of BBC, continues alive, when it is so obviously wrong.

But enough of personal anguish and Sociology. How could the uncommitted thinker look dispassionately at the arguments for and against BBC and come to a balanced opinion?

There is a way – using Common Sense – if you know how it works – which most scientists, let alone other scholars, do not. All it will deliver is a provisional conclusion, with some kind of Odds on it attached. What I will do next is to exhibit two different attempts of mine to have a go at the BBC problem, so that readers can appreciate some of the philosophical subtleties involved.

The first, entitled “Doubts about Big Bang Cosmology” was published back in 2011, where my Odds against it being broadly right were only 4 to 1, disappointing, but hardly decisive. It is reasonably short yet contains the main arguments in a not too technical fashion I hope, so readers may care to see how those Odds were reached. You can find it at

https://mjdisney.org/wp-content/uploads/2021/02/Doubtsbigbang-copy.pdf

In cosmology itself nothing much changed dramatically over the next 4 years. But my understanding of Common Sense did when, in 2015, I stumbled upon the vitally important PAW or ‘Principal of Animal Wisdom’, indispensable to all thinkers who might otherwise be blown wildly off course by Systematic Errors. Now my Odds against BBC shot up dramatically to 128 to 1 against it being broadly right. Not only are they far more conclusive but they are , in my opinion , far more robust too because they rely on a whole network of interlocking and broadly concordant evidence. Without any need to repeat the cosmological arguments the new Inference Table, with its condemning Odds O(H|E) {i.e Odds on the Hypothesis H given all the evidence E} is briefly exhibited at

https://mjdisney.org/wp-content/uploads/2021/02/SCAMBBCTable-copy.docx

The conclusion I would draw from all this is that the Universe is trying to tell us something profound and interesting about itself, but we professionals, soaked in our preconceptions, and deafened by our Church choir, are unprepared to listen. After Galileo’s experience we should have anticipated, and some of us on board the Hubble did. But ….

Our susceptibility to misconceptions lies in our weak grasp of Common Sense today, and in particular our total ignorance of PAW, or The Principle of Animal Wisdom. Animals whose very survival depends on sound judgements, cannot afford to be taken in by misleading clues. So how do they discount them? That was the question I asked myself back in 2015. The answer is they cannot allow any single clue a predominating Weight – because that clue might be false, and fatal. They must rely on a network of weaker clues which reinforce one another. That is what I call PAW. And when I apply it to BBC the Odds against it shoot dramatically up. BBC can’t be right, it can’t. Something at least about it is deeply wrong, never mind the technical details. [To see more on the PAW go to Post ‘ANIMAL WISDOM & US’ in ‘Thinking’ Category].

If the PAW is so damned vital for animals then how did we ever lose sight of it? Because Priests preach Certainties – their influence, their power and their livelihoods all depend on proclaiming Certainties, whilst the PAW stands out firmly against them. And, to be fair, many of us prefer Certainties to uncomfortable uncertainty – which is all the natural world has to offer. So over the last few thousand years the PAW, which is grown-up, has become submerged by a childish and misbegotten craving for Certainty, which only priests, but not men of Common Sense, can deliver. As Voltaire put it: “Uncertainty is uncomfortable; Certainty is absurd.” See a talk on Youtube by me on this topic at

https://www.youtube.com/watch?v=KskJrJmfr34

What IS the universe trying to tell us ? It could be exciting.

HOW DARK IS THE NIGHT?

November 10, 2020

My trade as an astronomer , involves travelling to the very darkest spots on Earth, peering up to see what is there, and returning to report to you, my fellow humans. You poor devils can’t see much of the splendour because you have blinded yourselves with artificial lighting.

These expeditions into the dark started in the Arizona desert, then on to the Warumbungles in the Australian bush, to the island peaks of Hawaii and La Palma, and finally to La Silla up in the Chilean Andes where I measured the darkness in between the stars at 22.5 Blue magnitudes per square arc second. In my ignorance I was impressed though I was disappointed to see little more from up up there with the naked eye than I could espy from a moonless beach in Wales. ‘Why not?’ I wondered.

It turns out that the rod cells in the eye, which enable us to see in the dark — if we treat them properly, are critically dependent on Oxygen. Climb a mountain, where of course all our telescopes are constructed, and you’ve lost it. I discovered that by accident when I woke up in the bottom of my little sailing boat up a remote creek in West Wales to find a colossal glow several moon-widths across, peering down at me from on high. Yes I’d had a few pints but….surely…. It took minutes to realize that I was being watched by the Andromeda Nebula, our fellow Spiral galaxy, which I’d never seen before, even from those remote mountain peaks. [Try it for yourself on a moonless night in summer. Get as far away as you can from city lights, and go to sleep in the open (that ‘dark-adapts’ ones eyes), then wake and look up — and with any luck you might see a marvel you will never forget.]

This is a composite image showing just how big The Andromeda galaxy is compared to the Moon. It’s really worth looking for. Copyright Adam Block and Steve Puckett.

Why hadn’t the big telescopes I’d been using make much difference? First because their fields of view are far too small. Second because the light you want to see is accompanied by much more background sky-light that you don’t. The big mirror amplifies both, only weakly improving the contrast. And that is what one needs to discern the dimmest structures in the universe — more contrast!

When I joined the Hubble Space Telescope Team it was natural to suppose that seen from up there in Space the sky would be really dark. But no. In between the planets drift tiny motes of dust which reflect sunlight back down into our dark — the so called Zodiacal Light — which you can actually see , if you know where to look. So disappointment once again.

Perhaps, if we could escape from the Solar System? But no again; there will still be faint starlight out there from the Milky Way and scattered starlight too. What a disappointment. Is there nowhere in the cosmos from where we could see the Universe as it really is? What about out there between the galaxies out in Intergalactic Space? You and I will never be able to go out there, but perhaps our distant descendants?

If I couldn’t go at least I could calculate how dark it ought to be out in that farthest, remotest, darkest immensity, an unimaginable distance away from any luminous star. It wouldn’t be absolutely black of course because some light would still be leaking from the nearest galaxies several million light years away.

What a shock I was to get from my calculation when I finally made it in my eighties. Out there the sky would have a brightnesss, or rather a dimness of 31.5 Blue magnitudes per square arc second, 9 magnitudes darker than the darkest site on Earth (Remember? 22.5 of the same magnitudes in the Andes). Now 5 magnitudes is one hundred by definition, so 9 magnitudes is one hundred times forty, or four thousand. Turn the calculation around and you can see why I was stunned. We live on a planet where the darkest night sky we will ever see is four thousand times brighter than it has to be if we are ever to see the Universe properly . We’re dazzled, blinded, blind. It is far more likely than not that we are blinded to most of the structures out there, and that all we will ever see, for all our technology, is a tiny fraction of the true Universe. Think on that. Knowing what we cannot know is sometimes more informative than knowing what we can.

If you want to see how the calculation was done go to:

https://mjdisney.org/wp-content/uploads/2020/11/hgreview7sept-1.pdf

HIDDEN GALAXIES, HIDDEN UNIVERSE

November 6, 2020

Hidden Galaxies were Tom Morgan’s passion (and mine). We both fell under their spell when we were young and spent our lives, and other people’s too, searching for them. Were we mad, as many sensible astronomers thought, or were we lucky? After all, searching for a vast continent whose existence could only be inferred from coincidences and equations, seems close to insanity. But then Christopher Columbus had been driven to his own folly by finding tropical beans washed up on the wester shore of Ireland, and by scraps of manuscript written in Egypt but then left forgotten for a thousand years on a library shelf in the great dome of Byzantium — Agia Sofia.

The saga of of Morgan’s life-long obsession ( and mine) is the spine of my quartet of novels Written in the Stars, starting with Against the Fall of Night (AFN) and ending with Beyond the Western Stars (BWS), a sort of Sidereal Odyssey I won’t retell here. But what I can do for non-astronomers is add some scraps of the evidence, the tropical beans if you like and the pieces of parchment which kept Morgan and his comrades going when all the Odds looked to be against them.

The Wigwam diagram showing the Visibilty of any galaxy (upwards) plotted agains its dimness, plotted horizontally, dimmer to the right. It is the consequence of two plunging curves and so is very sharp and very thin, which surprised everybody. It is utterly unintuitive, yet entirely dominates our ability to see the extragalactic universe. It turns out that virtually all the galaxies we can measure lie right under the peak. That is either a miraculous coincidence or a warning that most galaxies are hidden out of sight.

Let’s begin with the calculation Morgan made back in 1975 in that caravan on the Teifi Estuary (AFN). Above we see it in the form of a graph. It shows the Visibility of a galaxy — that is to say how easy it will be to see, plotted upwards, against its dimness, plotted towards the right along the bottom. And what Morgan found, to general consternation and surprise, was an extremely sharp, narrow peak. The inference was that only galaxies of a very particular dimness (or ‘surface brightness’ in the jargon) would be visible to mankind. Those ones to the right (‘Icebergs’ Morgan called them) would be sunk too far below the night sky, whilst the ones to the left (‘Brilliants’) would be so small in apparent size as to be mistaken for background objects And here was the killer-coincidence: all the galaxies known to science at the time fitted exactly underneath Morgan’s peak. That is why the paper, with its implicit challenge, was published in the journal ‘Nature’ in 1976. What the diagram The ‘Wigwam diagram” as we came to call it, cannot convey is just how narrow the Wigwam really is. It is ten thousand times narrower than the total range over which the occasional galaxy has turned up by accident. Ten thousand times! Even Morgan sometimes couldn’t believe that. Apparently we are looking at the universe through a mere crack in the shutters. It was the Wigwam diagram which kept Morgan and his crew sailing on, through doldrum and tempest, for the next forty years.

Astronomy is beset by what are called “Selection Effects”. That is to say we build our picture of the cosmos selectively out of what we can observe down here, pretending that what we cannot observe, which might be much the greater portion, is not significant. What else could we do? Morgan’s wigwam was thus a rude shock, for it suggested, very directly, that Astronomy must be missing much of the extragalactic cosmos. What could be done about that? We had to try and devise alternative observing strategies which might enable us to see through one window, what could not be seen through another.

ICEBERG GALAXIES

Using that approach Morgan and his colleagues decided to survey the sky in the radio band, and when they found a source, check what was there in the optical. The next figure shows some typical results, with a radio spectrum superposed on a negative image (easier to see) of the corresponding area of the visual sky..

Here are radio scans of the sky made with the Parkes Radio Telescope superposed on negatives of the optical sky behind. The receiver is tuned to the frequency of gaseous Hydrogen receding from the Earth at the velocities ( in Km/sec) shown at bottom. The two upper spectra corresponded to giant spiral galaxies, bottom left to a dwarfish Irregular galaxy, and bottom right to a dim galaxy barely visible above the sky. The area under each spectrum is a measure of the total amount of gas present while the width derives from the internal motions within the galaxy ,such as rotation. Much can be inferred from these measures. Copyright Monthly Notices of the Royal Astronomical Society.

Usually there is indeed a galaxy to be seen there. But of course the team were hoping to find cases where the optical counterparts were invisible — i.e. true ‘Hidden Galaxies’

A montage of galaxies found at Parkes and then observed in several colours with the Sloan Survey Telescope in New Mexico. The six bottom right are all colossal giants more massive than our Milky Way. Nevertheless, as you can see, some are very dim. This all ties in with the Wigwam diagram and indicates just how treacherous a purely optical survey of the Universe might be. Courtesy of Professor Julianne Dalcanton, University of Washington, Seattle

The figure above shows that, from time to time they came close. Each postage stamp in the montage shows the optical image corresponding to a radio signal found in a blind survey of the sky made with the Multibeam Receiver fitted to the Parkes Radio Telescope in Australia. As you can see some are almost invisible, lying in the very wings of the Wigwam diagram. It is important to emphasise that the Luminosity of a galaxy (which corresponds to the number of stars it contains — generally billions) and its surface-brightness (dimness) are entirely different concepts, the latter depending on how its Luminosity is spread out across the sky. Although the six galaxies bottom right are all luminous giants, some are nevertheless, extremely dim.

There is another trick though in astronomy for finding something invisible in Space: observe an object behind it and look for tell-tale gaps (‘spectral ghosts’) in its spectrum where specific atomic species in the invisible object have absorbed out the light coming from behind. That is what Frank Cotteridge and his like found, albeit by accident, when they observed the spectra of very distant Quasars — lots and lots of inexplicable absorption lines (‘spectral ghosts’). “What else could they be”, Morgan argued, “If not my Hidden Galaxies?” Thus the bitter battle over QSOALs or ‘Quasi Stellar Object Absorption Lines’ began (see especially “Crouching Giant“).

The spectra of Quasars showing the many absorption lines (spectral ghosts) etched into them. Measurements show they are caused by clouds of atoms like Hydrogen and Nitrogen lying in the foreground along the line of sight to the quasar. But what form could those clouds take? Morgan claims they are the numerous Hidden Galaxies you would expect. Opponents who don’t like that idea are forced to postulate that visible galaxies must have absolutely vast gaseous halos surrounding them. Controversy continues [see Whispering Sky and Crouching Giant in particular]. As you go down the montage one is looking at higher and higher redshift quasars. Out there, back in time, the absorbing clouds appear to have been crowded closer and closer together. The humps are features in the spectra of the Quasars themselves. Copyright The European Southern Observatory (eso.org).

In 1987 the whole field was electrified by a paper written by Greg Bothun, Chris Impey and colleagues who were then based in California. Quite by accident, while observing dwarf galaxies in the nearby Virgo Cluster, they noticed that one wasn’t a dwarf, but the nucleus of a “Crouching Giant”, that is to say of an absolute monster of a spiral galaxy 25 times further away than the cluster but too dim to show much of itself above the sky. Here was unequivocal evidence that Hidden Galaxies of the most dramatic kind actually existed.

The Crouching Giant found by Greg Bothun, Chris Impey and co. by accident in 1987. The bright nucleus (this is a negative) was thought to be a dwarf galaxy in the nearby Virgo Cluster. But some very smart detective work revealed that it was instead the core of an absolutely colossal but dim giant spiral 25 times further away, whose spiral arms you can just pick out. It is no less than half a million light years across, ten times the extent of our own colossal Milky Way. Because of the accidental way it was found, finding others like it would be infernally difficult. Copyright Astronomical Journal 1987

That might have been that — except that nobody could find another such. The sceptics could, and did, write it off as a freak. If Hidden Galaxies were to become ‘significant’ they needed to make up a healthy fraction of the cosmic light and mass. In other words astronomers needed to find lots of Crouching Giants.

And how we all tried! But even when Jon Davies & co. did find one at Jodrell Bank (below) the opposition was fanatical.

Theoreticians who’d ‘proved’ that Hidden Galaxies couldn’t exist were furious; observers with even bigger telescopes than Jodrell were adamant that if they hadn’t found one then certainly we could not. And then there were the computer modellers who, at the drop of a hat, could prove or disprove anything, often without acknowledging the manifold frailties of their craft.

The putative Dark Galaxy VirgoHI-21 in the Virgo cluster. Left shows the radio contours superposed on a negative optical image. (Data obtained with the Westerbork Array in Holland) The giant spiral NGC4254 has obviously been disturbed by an encounter with a massive object which could only be Virgo HI-21, which is Dark, but note the bridge of gas between them. But the dynamical map (Right) shows it is spinning rapidly which can only mean that it is indeed massive. Massive, dark, spinning; what else could it be but a Dark galaxy? Copyright The Astrophysical Journal, 2007.

So although , after titanic refereeing battles, Virgo HI-21 did eventually get published in the prestigious Astrophysical Journal, most of the self appointed ‘experts’ stubbornly refused to acknowledge it as the first Dark Galaxy. But, in my opinion, if you read all the arguments carefully enough, it cannot be anything else.

In Big Science the problem is very often Lack of Breadth, rather than Lack of Depth. The clues are here and there but who has the breadth to spot them all, and assemble a coherent picture? Often we fail because no one individual in the field has the required breadth. And then there are the Systematic Errors that can bedevil any ambitious undertaking, errors held on to fanatically, especially by those who do not appreciate the frailty of The Scientific Method, and the need for caution in applying it (See my book Thinking for Ourselves) . This is highlighted in the following image based on observations we made with the Jansky Telescope in New Mexico, much the most powerful radio telescope on Earth at present. It reveals a huge cloud of hydrogen, the signature you would expect of a Dark Galaxy, but with a giant but optically visible galaxy to the South, receding away from us at the exactly the same speed as the Hydrogen. Previously the Parkes team, to which I then belonged, had mistakenly identified that as the source of the Hydrogen, and so overlooked what appears to be a true dark galaxy. Galaxies, Dark or Light, cluster so gregariously together that one needs a very powerful beast like the Jansky, to distinguish between them. None of us fully appreciated that, certainly not the Quasar observers with their spectral ghosts, who could always postulate, around visible galaxies, ‘gaseous haloes’ of unlimited size, to discount the invisible ones, which is what most of them choose to do.

What a Dark Galaxy ‘looks like’. Parkes 0039+03 was first discovered as a massive Hydrogen source out at 5,300 km/sec recession-velocity by Morgan and co. using the Parkes dish. They mistakenly associated it with the luminous optical galaxy (marked ‘cont’ here ) which happened to have an almost identical radial velocity, even though it is rather far away on the sky. But much later these more precise observations with the colossal Jansky array revealed that the Hydrogen and the bright galaxy are unassociated, as you can see. Even later a much deeper optical observations of the cloud made with the William Herschel 4.2 metre telescope in the Canary Islands revealed that it has tiny patches of light in it, but that is all. The strong clustering of galaxies together, both in space and in velocity, makes the search for Dark galaxies far harder than anyone had imagined. But if this isn’t a dark galaxy then what is? We found more like this out there.

BRILLIANTS

Thus far I have spoken entirely of Icebergs, hidden below the sky on the right hand (dim) side of the Wigwam; what about the ‘Brilliants’ on the other? They would be even harder to find so Morgan and co almost forgot them altogether. Apart from anything else, being compact, they would be largely shrouded in their own smoke, disguising their true brilliance, appear like ordinary galaxies, but far far in the background, and therefore of no particular interest.

It was only after WFC-3 was operating on Hubble (2009) that Morgan began to worry about the extremely high redshift galaxies dotted all over the background in deep Hubble images (see below). If the universe were really expanding they oughtn’t to have been there — dimmed out of visibility by the so called ‘Tolman Effect’. And they turned out to be very small physically, much smaller than galaxies of the same luminosity situated close by to us in Space. Then the penny dropped with a clang for Morgan. Here were his Brilliants but at very high redshift, dimmed just enough by expansion to place them in the Visibility Wigwam where they became possible for us to see. The implications though were startling: Space must be inhabited by vast numbers of Brilliants , just as it probably was by Icebergs. And together all their extra radiation would have sufficed to re-ionise the Universe — otherwise a major problem for Cosmology. So it all fitted together: Hidden Galaxies, Expansion, Brilliants, the Wigwam diagram, Reionisation…….if Morgan was right. If…….. This was the theory which obsessed him towards the end of Beyond the Western Stars.

The Hubble Ultra Deep Field, the deepest image ever taken. In an expanding universe distant galaxies ought to be dimmed to the point of invisibility by straightforward physical effects. Yet here they are, dotted all over the place. Either the universe isn’t expanding or these are normally invisible Brilliants, shifted into the Wigwam by redshift so as to be visible. Courtesy ESA/NASA

Who was right, and who was wrong can only be decided by posterity . But in my story of Hidden Galaxies I have tried to convey, above all, just how engrossing it all was: the tournament of ideas, the clashes of personality and ambition, the conflicts of evidence, the camaraderie, the bravery and the cowardice, the wild misunderstandings and the hazards of fortune……. They make science such an exciting career; though not one for the faint-hearted.

PS. I have actually left out the biggest reason for mystery here, because it has a post of its own entitled HOW DARK IS THE NIGHT?

Professionals who would like to see a fairly up-to-date review of this subject can look at my opening address to the International Astronomical Union symposium No.355 held at the IAC in Tenerife in 2019 entitled “The Realm of the Low Surface Brightness Universe” (Procs. edited by David Valls- Gabaud to appear soon in CUP) at:

https://mjdisney.org/wp-content/uploads/2020/11/hgreview7sept.pdf

THE HUBBLE SPACE TELESCOPE

November 5, 2020

Given that there are roughly ten tons of turbulent murky atmosphere above every square metre of the Earth’s surface it is a wonder that we can see the Cosmos at all. Thus the urge to orbit a big telescope above that atmosphere was irresistible. So in 1976 NASA and ESA put together a joint mission , which was eventually to be christened ‘The Hubble Space Telescope’ (HST) after Edwin Hubble. If, and it was a very big if at the time, all went according to plan, the prospects were breathtaking. The machine would image the Cosmos in a thousand times more detail, and across an eight times greater colour range than its ground based counterparts. Because of its accuity it would begin to see the Universe actually moving for the first time. Furthermore it ought to detect objects a hundred times fainter and thus ten times further away, and because light has a finite speed that meant it would be a Time Machine able to observe the Universe as it was long before the Earth and Sun were born. No wonder some suggested it would become “the most exciting project ever undertaken by mankind”.

This illustration shows the NASA/ESA Hubble Space Telescope in its high orbit 600 kilometres above Earth. It’s about the size of a bus while the ‘wings’ are solar panels

But if it was to succeed there were huge challenges to overcome. How was a mirror of the required precision ever to be made? How could the telescope take pictures up there and then return them to Earth? Given that there would be no crew (too clumsy), how was it first to find its targets and then hold steady on them with unheard of precision? How could it be serviced, or repaired if things went wrong, as they were bound to do on on a spacecraft far more complex than any nuclear-powered aircraft carrier?

Nobody knew the answers. But that was half the point. Like JFK challenging the Apollo Mission to get to the Moon in the 1960s “……not because it is easy, but because it is hard” so NASA and ESA were throwing down the gauntlet to their successors. “Here” they said to their selected teams “Here’s a problem we can’t solve. You go crack it. But you’ve only got so long!” And that of course was the very kind of challenge which inspires scieneers.

Astronauts installing WFC-3 camera on Hubble Space Telescope in 2009

Teams, committees, call them what you will, were the secret, and the Camera Teams were at the very heart of the entire enterprise. Only the cameras on board could exploit the full power of the telescope, and so deliver its most ambitious science. But what was that science to be? Before they designed a single lens it was those instrument teams , and those alone , which had to peer far into the future and try to imagine the most exciting questions that the telescope would be called upon to answer.

I was lucky enough to attend the first meeting of the Faint Object Camera team in 1977, and the last meeting of the Wide-Field-Camera-3 team, in 2010. So I feel well placed to describe our long voyage of discovery, as one of the on-board crew. I have chosen to tell it in novel form because what was to happen had to first germinate in the human heart and mind, the drivers of everything else. It also allowed me to cut many a tedious corner while keeping the true cast of thousands to less than Tolstoyian size. I hope readers, and in particular fellow members of the crew, will forgive me for that, and certainly for omitting episodes and heroes they feel should have been included. But this is meant to be a human story of a very human endeavour, not the synoptic history which will no doubt emerge when we have all gone.

Since The HST story occupies much of my three novels:

The Whispering Sky ( 1976 to 1983)

Crouching Giant (1983 to 1995). and

Beyond the Western Stars (1996 to 2011)

all Amazon Publishing (2020)

I won’t say more here. You can see then all described here under the ‘My Books’ Category.However I intend to add, from time to time , images and scraps which could enrich the reader’s experience of the adventure. and I would be grateful if readers, or ex-comrades, could suggest more.

Here is the recent Ultraviolet Ultra Deep Field image taken with Hubble WFC-3, the deepest picture of the universe ever taken, and illustrating its capability as a Time Machine. Apart from the odd spikey star all the objects are galaxies vast distances away. The tiniest reddest ones have redshifts as large as 7 indicating that we are seeing them as they were over ten billion years ago. The Sun is only 5 billion yeas old. Copyright NASA/ESA/stsci.

Hubble would have been a disaster without the Space Shuttle, which not only launched it back in 1990 but visited it 5 times thereafter, to adjust for the flawed mirror, make innumerable repairs, and install new instruments like WFC-3, the camera which is still up there working perfectly after 11 years in orbit. Man seldom gets things right first time; we do our best by tinkering, by Evolution. Without Shuttle that would not have been possible, and I fear that HST’s successor, the James Webb Space Telescope, whose launch has been postponed at least a dozen times already, could be a disaster because it has no such means for repair. Anyway below you will see a panoramic view of the Cape Canaveral launch-site in 2009 with Shuttle Atlantis on Pad 39-A about to go up on its final mission STS 125 to the telescope, carrying WFC-3, along with its brave crew. In the background is Shuttle Endeavour on Pad 39-B, standing by to act as a Lifeboat to bring the crew back should Atlantis experience a serious failure, as happened with Columbia. In the background is Merritt Island nature reserve. If you zoom in enough, you might spot Morgan swimming up one of the alligator infested creeks to get as near to Atlantis as he could.

Those interested in following up the treasury of wonderful Hubble images and what they signify, can go to websites such as stsci.edu, nasa.gov, eso.org , http://www.cosmos.esa.int, and http://www.spacetelescope.org.

GALAXY GALLERY

October 26, 2020

Morgan, the protagonist in the Written in the Stars quartet, and I, have spent our working lives studying Galaxies. This is the first one he saw when he was looking through the 36-inch telescope at Steward Observatory atop Kitt Peak in Arizona, back in 1969.

Spiral Galaxy NGC 7331 in the constellation of Pegasus, at top. Courtesy, Vicent Peris, University of Valencia.

This particular image was taken much later with a huge telescope 3.5 meters in diameter fitted with an ultra-sensitive electronic camera integrating the light for two whole hours. So imagine how little if anything Morgan would see with the naked eye which integrates for all of a tenth of a second, through his much smaller telescope: virtually nothing at all. That’s why he struggled for half an hour to even convince himself that it must be there, and why he felt that studying galaxies could become the lifetime challenge he was looking for. And so it came to be.

NGC 7331 just happened to be the nearest Spiral overhead his telescope at the time. All the spiky stars are stars in our own galaxy the Milky Way, just hundreds of light-years away, while the spiral lies 45 Million light years beyond them, yet is one of the closest such giant spirals to us.It is about a hundred thousand light-years across! The smaller galaxies lower down are even farther off. Morgan was to spend most of his astronomical life studying galaxies whose light had set out towards him when dinosaurs still ruled the Earth, and some so far away that the Sun and Earth didn’t even exist when their light was emitted.

Even now we know little about these beasts; they are full of mysteries. For instance they spin so fast that they ought to fly to bits. So what holds them together; certainly not the stars we can see in them — their gravitational force would be far too weak. Some astronomers mutter about “Dark Matter”, but what is that, and why have we detected no sign of it after 50 years of searching with every ingenious means we can think of? Then we have no idea how galaxies formed, not if the Universe is really expanding, for their infant stages would have been far too fragile to survive the Big Bang. Galaxies remain a challenge for any young person who would like to spend their lives trying to understand what is out there.

Hard as it was to see, it turns out that NGC 7331 is one of the most visible galaxies there are. Over the course of 50 years Morgan and his colleagues were to find much much dimmer specimens using radio waves instead of light. The next montage shows some typical specimens first located with the Parkes Radio Telescope, then imaged in visible colours with the Sloan optical Telescope in New Mexico, both absolutely state of the art instruments. Its worth studying this montage:

Galaxies first found independently of their light signal in the radio, then imaged optically in several colours (Courtesy Julianne Dalcanton, University if Washington, Seattle).

Believe it or not every postage-stamp contains a galaxy, some so dim one can barely spot them. This illustrates the “Visibility of Galaxies” problem which Morgan discovered in that caravan on the Teifi estuary back in 1975 [See my book Against The Fall of Night]. The problem is that, dark as it appears, the night sky is not absolutely dark so that any galaxy dimmer than our sky would be invisible. And why not? Could most of the structure of the Universe be hidden from sight? Morgan, Cotteridge, Cockle and other astronomers spent their careers wrangling over that question. There’s a great deal to think about here.

Broadly speaking there are two types of giant galaxy, Spirals as above, and Ellipticals. As we can see next, Ellipticals look like giant swarms of bees ( actually very old stars).

The Coma Cluster of Galaxies centred on the supergiant Elliptical NGC 4889 taken with the Hubble Space Telescope, courtesy ESA/NASA.

Ellipticals are just as mysterious as Spirals but in somewhat different ways. For instance NGC 4889 seen here fades imperceptibly into the sky; so where does it end and therefore how big and how massive is it? And why are Giant Ellipticals only found in Clusters? And where have the cold gas and the young blue stars gone that light up Spirals? And why do some of them, like this one, have colossal Black Holes in their cores? And how do these giant Clusters hold together when the gravitational forces required are hundreds of times too weak , if only visible material is responsible. Once again we run into speculations about “Dark Matter” which sound a bit like The Emperor’s New Clothes to me. In other words we are mired in mysteries which challenge anyone with Curiosity. By the way, this colossus is about 300 Million light years away, its light having set out towards us even before Dinosaurs evolved and 50 million years before the great Permian-Triassic extinction, which wiped out 90 percent of the the species on Earth. Yet in astronomical terms it’s almost next door, only seven times as far away as our Spiral friend NGC 7331.

We said most galaxies dwell in Clusters containing anything between a few and tens of thousands. Here is a very large Cluster Abell 1689, 2 Billion, not Million, light years away:

Galaxy Cluster Abell 1689 imaged with the Hubble Space Telescope (Courtesy ESA/NASA)

The further away we search , the further back in time, the greater cosmic mysteries become. For instance what you can actually see here is about one per cent of the Mass actually present. We know that because the galaxies in the cluster are whizzing about so fast that the cluster would have dispersed unless there are overwhelming amounts of “Dark Matter” holding it together [Or else there’s something even more mysterious going on.] This dramatic tendency of galaxies to cluster made it very difficult indeed for Tom Morgan and his friends to find “Hidden Galaxies” because the hidden ones would tend to get lost amid a crowd of ‘Visibles’, requiring great precision to get at the truth.

This, believe it or not, is the identical galaxy NGC 7331 to the one at the top of this post, though the image is flipped left to right..I have put it in for several reasons. First it is in colour because it was made up from several images taken through different colour filters with camera WFC- 3 ( Morgan & co.) on Hubble . This colour information paints a very different picture of the galaxy, which is evidently choked in smoke, so that much of it is hidden. Using the old photographic plates little of this was evident and astronomers were convinced galaxies were transparent. Morgan was practically the first astronomer to realise they were not, largely because he had early access to one of the first electronic cameras. Then there is the atmosphere which blocks off all the ultraviolet, and most of the infra-red radiation included in this picture taken from Space. The general point is that our understanding of the universe is very much constrained by the instruments we have to study it. Space astronomy has widened our spectrum by more than a billion and it may take generations to understand the implications. It’s all too easy to rush to judgement, and to see only what we want to see. Copyright ESA/NASA

When we professional astronomers talk to the public we tend, for sociological reasons, to emphasise what we do know, as against what we do not. Now that I’m retired I can admit that most of the time, at least in extragalactic astronomy, we have little idea of what is really going on. Yes there are fools only too ready to rush in with half-baked explanations such as “Dark Matter” or “Dark Energy”, but I doubt that many will stand the test of time because they ignore Ockham’s Razor, a very profound and vital principle of Common Sense [See my book Thinking For Ourselves or a post on this site entitled Fuzzy Thinking and Ockham’s Razor]. In the mean time they not only rob us of mystery and wonder but they can hold up the search for deeper truths. For instance the invention of fictional “Land Bridges” held back the discovery of Continental Drift by a century.

I hope this post encourages readers, especially the young at heart, to retain their sense of mystery because, as Einstein put it : ” The most beautiful thing we can experience is the mysterious. It is the source of all true art and science”.

You can look up hundreds of more wondrous images of galaxies by going either to stsci.edu, NASA’s Space Telescope institute, or eso.org the European Southern Observatory which runs the world’s largest optical telescope (The ‘VLT’) in the Chilean Andes. But beware of beautiful coloured images which look like pizza advertisements; real galaxies don’t look anything like that, they’re far more subtle and infinitely more difficult to decode.

THE SCEPTICAL COSMOLOGIST

October 13, 2020

 

Somebody said, Einstein I believe: “The most beautiful thing we can experience is the mysterious. It is the source of all true art and science .” And no subject is so imbued with profound mysteries as Cosmology – despite what some glib professionals would have us believe

Think of Cosmology’s Big Questions:

1) Why is the sky dark at night – if the universe is infinite?

2)  Why do distant galaxies have highly red-shifted Spectra?

3) Is the universe changing, and did it have a beginning?

4) What is the source of the powerful cosmic background radiation which glows in all directions?

(5) How can that radiation be so uniform (To one part in a hundred thousand) if the speed of light is finite – which it definitely is?

(6) If the universe is expanding in a hot Big Bang – which so many professionals maintain – then how did flimsy structures like galaxies form out of it? Nascent galaxies should have been torn to bits by radiation pressure.

(7) When you slam the brakes on  in your car, why does your head jerk forwards ? It is being violently decelerated, but decelerated relative to what? It turns out that it is being decelerated  with respect, not to the Earth,  but to the distant stars. But how does it know that? ( ‘The Problem of Inertia’ ). In other words what is the physical mechanism that  must connect your head to the stars?

These are all profound and mysterious questions to which science has so far been able to offer only fumbling answers  –   despite what some cosmology-priests would like us to believe: “The universe is expanding,”  they say, “There was a Big Bang, Space – Time is curved, and we’ve got answers to all, or nearly all those other awkward questions too – Cold Dark Matter, Inflation, Dark Energy……”

Don’t believe them. Cosmology is an extraordinary difficult subject if only because it lies at the nexus of so many others: Astronomy, Physics, Mathematics, Philosophy, Sociology, Instrumentation, Computer -simulation…… Of the sixty different civilisations we know of, every single one has come up with a cosmology of sorts – it seems to be a necessity for the human psyche. And that leaves room for a priesthood only too eager to supply one.

To keep a sense of proportion it is worth recalling some recent cosmological follies:

Thinking of Time as linear: “We’re already back to within three minutes of the Big Bang” they say  – when, in the cosmological  context, Time is surely logarithmic. In logarithmic Time the Cosmos was completely opaque throughout the first 43 decades of its 60 decades of existence. Its origins will therefore be veiled  beyond our sight – probably for ever.

If galaxy redshifts are not the Doppler effect in action – which apparently they are not – then what causes them? Yes, they come out of the mathematics (the ‘Robertson – Walker – Metric’), but that is hardly Physics.

Once the impossibility of forming galaxies in a Big Bang cosmology was recognised, an ingenious new substance christened ‘Cold Dark Matter’(CDM) was conjured up to solve it. Elaborate computer  simulations were offered as proof that CDM works. But it doesn’t. Observed galaxies look nothing like the CDM variety; nothing like1. Yet the cognoscenti refuse to admit it.

Everyone agreed that gravity ought to slow expansion down but when the slowing was looked for it wasn’t there. On the contrary. Expansion had apparently accelerated – and in recent times too. This called for another improbable miracle: Dark Energy – whatever that is.

If expansion of the entire universe does seem  a mite implausible – we do have an acid test for it – the Tolman Test devised in the 1930’s [distant galaxies should dim as the fourth power of their redshifts]. But one glance at the Hubble Deep Field (below) demonstrates that there is no such dimming – it falls short of the required  amount by  a factor of no less than 10,000! But professional astronomers  won’t talk about that. Why not?

           In short Cosmology appears to have been regressing of late because some of its  most vocal proponents appear not to appreciate  a truly  fundamental principle of Philosophy – Ockham’s Razor. Every time you complexify a theory by introducing a new Free Parameter (such as Dark Energy) to solve one problematical feature of it, you fundamentally weaken that theory. So one is only justified in doing so if at the same time that Free Parameter illuminates other entirely new and favourable evidence which more than compensates for the weakening inevitably involved. CDM, Inflation and Dark Energy do not meet that criterion  – and so should be rejected.

           I have been an enthusiastic follower of Cosmology since I was a boy. I even taught  myself Tensor Calculus at age fifteen in order to read Einstein’s original papers. I’ve been a professional extragalactic astronomer for much of my life and have been to some of the big cosmology conferences – including one in the Vatican ( see my book Crouching Giant),  even taught it at university when nobody else would  – but have  become gradually more and more sceptical of the subject as the years roll by. Yes there are some strong arguments in favour of  Big Bang Cosmology – but there are even more against. To come to a measured  view of the whole subject one  needs to weigh them against one another  using Common Sense. When I do so the Odds come out at over hundred to one against Big Bang Cosmology being  broadly right( See another post here entitled  The Scientific Method.) Some aspects of it are probably sound, but which ones?

I’m not suggesting we should abandon  Cosmology as a subject  –  on the contrary. We should study its mysteries with ever more ingenious techniques and instruments. Equally though we need to be  alert  to the crippling weaknesses of the current paradigm. If we close our ears to them, as so many professionals at present do, we could miss some subtle but tremendous secret the real universe is trying to whisper in our ear. As Daniel  Boorstin wrote in The Discoverers: “The greatest obstacle to discovery is not ignorance – it is the illusion  of knowledge.” I believe we all need to become sceptical cosmologists now; most especially professionals.

Hubble Ultra Deep Field. Courtesy ESA/NASA

If you examine this extremely deep image taken with the Hubble Space Telescope almost every object on it is a galaxy . The small images are much further away and have high redshifts. But if those redshifts were due to expansion of the universe then those small images should be so dim as to be invisible. But as you can see they are nothing of the kind. This is a complete shock. On the face of it at least Cosmic Expansion has failed the classical test set for it — ‘The Tolman Effect’ by a factor of 10,000!

On the face of it then the Universe cannot be expanding! After all such dimming was the classic test for expansion proposed by Richard Tolman back in the 1930s when we didn’t have the means to apply it. But now we have, and the universe has spectacularly failed it. But nobody, at least no professional, wants to talk about it, Umm.

There is another more recent post on this site entitled “Big Bang Cosmology is Wrong” under the “Astronomy” Category

I go into the stories behind the Hubble deep pictures in the last 2 books in my quartet ‘Written in the Stars entitled’ : Crouching Giant and Beyond the Western Stars. [See under ‘my books’ Category on this site.

NB You can see hundreds of HST images at stsci.edu, nasa.gov. or eso.org.

Ref 1: Disney M J et al: 2008, Nature, 455, 1082-4, Galaxies appear simpler than expected.

If you want to see the author talking about Cosmology and galaxies there is a 45 minute Youtube video of him being interviewed by the Physicist and Author Alexander Unzicker about 3 years ago at:

https://www.youtube.com/watch?v=KskJrJmfr34

THE PARKES RADIO TELESCOPE

October 8, 2020

Parkes Radio Telescope New South Wales

The Parkes Radio Telescope in New South Wales Australia after it had been fitted with the new Multi-beam receiver system designed to pick up the Hydrogen signals from galaxies with about a thousand times the speed of any previous instrument. It has 13 separate dual-beams and 26 receivers cooled down close to absolute zero (minus 273 degrees C) up in the receiver cabin which is the size of a small house. Up there the very weak signals are mixed with a maser and the lower frequency output signals are sent down to the tower where they are processed by specially designed and very powerful digital correlators to look for the characteristic 21- centimetre wavelength signal of Cosmic Hydrogen. With it Morgan and his Australian colleagues surveyed two thirds of the sky and found over 5,000 such sources among which they hoped to find Dark Galaxies.[See Written in the Stars quartet of novels under ‘My Books’ Category]

The Dish has a romantic background. It was built by Taffy Bowen who, together with Hanbury-Brown, devised the night-fighter radar system which put an end to the Nazi blitzes in 1942. Starting at Bawdsey Manor in 1936 they devised means to cram radar systems into aircraft — which was fiendishly difficult to do in those days when radar waves were 10 metres long. But somehow, supported by Air Marshall Dowding, the head of RAF Fighter Command, they eventually did so.

In 1941 Bowen was sent to the US with his notorious ‘Suitcase Full of Secrets’ to teach the Americans how to build effective radars [See my book ‘History of the Brits‘ for that story ]. Later Bowen came to Sydney to direct the CSIRO Radiophysics Lab and the grateful Americans gave him half the money to build the Parkes dish which was completed in 1961. In 1962 Cyril Hazard from the University of Sydney used it to locate the first Quasar when the radio source 3C-273 passed behind the Moon. The disappearance and re-appearance of the radio-signal enabled Hazard to get a very precise position for it — which corresponded to that of a moderately bright star. An optical spectrum of that star showed it to have a high redshift and so to be an enormous distance away. The first Quasar Stellar Radio Source, or ‘Quasar’ had been discovered — starting off a whole new branch of Astrophysics — leading eventually to the discovery that they are Super Massive Black Holes.

Hanbury-Brown — after whom the term “Boffin” was coined, also made his name later as an astronomer in Australia. He it was who completed the night-fighter radar system which did for the Blitz and saved Britain [He features extensively in my Second World War scientific novel ‘Strangle‘ described in ‘My Books’ Category] .

The main weakness of radio telescopes is the non-existence of a ‘radio-camera’ which can look in more than one direction at once. The big box you can see at the focus was the first successful attempt at one. It has got 26 receivers looking in 13 adjacent but different directions at once — which allowed us to survey two thirds of the entire sky for Hydrogen gas in deep space — in the hope of locating Hidden Galaxies (see our Post ‘Hidden Galaxies‘). Unfortunately we then totally cocked things up by mis-identifying all the 5000 such sources we found with conspicuous optical galaxies , which is all too easy to do when galaxies are so highly clustered together in Space. Actually many of the Parkes sources are indeed dim or dark galaxies or gas clouds. Astronomy is hard….but very exciting!

ABOUT MY BOOK ‘THE WHISPERING SKY’

September 29, 2020

A novel about astronomical research

The Whispering Sky is the second of a quartet of self-contained novels relating the saga of two astronomers, originally boyhood friends, caught up in humankind’s endeavour to explore the Universe from Space. Thanks to his feud with Bellfounder – the machiavellian Astronomer-Royal [See ‘Against the Fall of Night’, first in the quartet], Tom Morgan has been thrown out of British Astronomy. Cheated out of the post he had been promised he struggles precariously in Europe to try and prove that his theory of Hidden Galaxies is right. That takes him to far flung observatories from the peaks of the Andes to the Cape of South Africa. Meanwhile the US is building the Shuttle to launch a large telescope into orbit but demands European participation in the venture. Frank Cotteridge, by now Bellfounder’s protégé, is tasked with lighting the European fuse. At conferences and in laboratories across the Continent the struggle begins to try and build the first electronic camera, to act as the great telescope’s eyes. In the 1970’s that looked impossible. And yet without such eyes the telescope will be blind. The race against the clock, and with rivals in California, begins. Personal and professional tensions drive wedges between the two friends while the race for Space forces them to rely ever more closely upon one another. Morgan rashly plans his revenge on Bellfounder, a battle only one of them can possibly survive.

This illustration shows the NASA/ESA Hubble Space Telescope in its high orbit 600 kilometres above Earth. Morgan and Cotteridge began working on its design back in 1977, 13 years before launch. Courtesy ESA/NASA.

At the same time Morgan is struggling, as a single parent, to bring up his son Curly and hold on to him in a bitter custody battle. When he loses, Curly is whisked away to Australia but then escapes and gets hopelessly lost in the bush.

The author was himself a professional astronomer, and a single parent, throughout this epoch. From 1976 until 2010 he was a key member of the Hubble Space Telescope team. Hubble’s story, our story, which he has been preparing to write for 20 years, is packed with dreams, heroes, shocks, villains, and the odd rare triumph. Like one of Magellan’s crew he saw great wonders and has tall tales to tell; the fight to get born, the Challenger disaster, the crippled mirror, the astronaut repair-missions, cancellation following the Columbia tragedy, renaissance, the race to prevent the space-craft dying, the huge discoveries… he was there; he was there; he was there. He knew the people, felt the pain, drank the wine. ENTIRE QUARTET ‘ called ‘Written in the Stars’ comprises: ‘Against the Fall of Night’ (1964 – 1974), ‘The Whispering Sky’ (1976 – 1983) , ‘Crouching Giant’ (1985 – 1995), ‘Beyond the Western Stars’ (1997 – 2012). All four paperbacks – each about 400 pages long – are out on Amazon, (2020), £12.99 or e-version £3.99.

ABOUT MY BOOK ‘AGAINST THE FALL OF NIGHT’

September 29, 2020

A novel about astronomical research

  Against the Fall of Night is a story about astronomical research, of one man’s battle to prove that there is another universe out there, hidden below the light of the night sky. It is centred in that glorious epoch between 1960 and 2010 when mankind at last broke free from Earth’s atmosphere and had to confront the Cosmos as it truly is: vast, mysterious  and very likely beyond his puny comprehension. But will he realise that, or seize on comforting fairy stories that will only serve to conceal the truth?  

Tom Morgan the protagonist, often facing starkly contradictory evidence, is suspended between exultation and despair. Half heroic and half tragic, his quest becomes an obsession which drives him round the world in search of the killer clue, forces him into confrontation with a highly sceptical Establishment.

Starting in the swinging London of the mid-sixties  the action moves on to remote observatories in Arizona, Australia, Africa, the Soviet Union, the Andes, Hawaii, …..and culminates on the launch pad at Cape Canaveral, for Morgan’s quest eventually leads him to become one of the designers of the Hubble Space Telescope.

Where so much of our story really began. This is Steward Observatory perched atop Kitt Peak, a mile above the Sonora Desert in Arizona. The 36-inch telescope left was used to find the Crab optical pulsar, and in the cylindrical 90-inch (centre) Morgan first started to think about Hidden Galaxies. Observers like him from the University of Arizona slept in the small buildings bottom right. The monster ‘4-metre’ was added later.

Morgan is no scientific cipher. An emotional single parent, he needs friends, comrades and lovers. He climbs, flies a glider, sails his boat and forges Van Gogh’s. Worse still he enjoys fighting a growing phalanx of enemies led by Sir Adrian Bellfounder, the unscrupulous Astronomer Royal. He is an extreme type: individual, competitive, irascible, passionate, imprudent. Throughout what will be a quartet, each part completely self-contained, but with the same central characters and spine plot, (see below) he is contrasted with his opposite, and lifelong friend and rival Frank, who has his own astronomical tale to tell. Frank  is the attractive, balanced, unselfish character who can get men and women to work together to build dreams beyond the reach of any single one. The story starts with the two friends leaving their universities, with very different prospects before them.

The author was himself a professional astronomer throughout this epoch. From 1976 until 2010  he was  a key member of the Hubble Space Telescope team. Hubble’s story, our story, which he had been preparing to write for 20 years, is packed with dreams, heroes, shocks, villains, and the odd rare triumph. Like one of Magellan’s crew he saw great wonders and has tall tales to tell; the fight to get born, the Challenger disaster, the crippled mirror, the astronaut repair missions, cancellation following the Columbia tragedy, renaissance, the race to prevent the space-craft dying, the huge discoveries… he was there; he was there; he was there. He knew the people, felt the pain, drank the wine.

ENTIRE QUARTET: ‘Written in the Stars’

  ‘Against the Fall of Night’ (1964 – 1974)  .

  ‘The Whispering Sky’ 1976 – 1983) ,

  ‘Crouching Giant’  1985 – 1995,

  ‘Beyond the Western Stars’ 1997 – 2014,

All four – each about 200 thousand words, i.e. 400 pages long have come out on Amazon, almost simultaneously (2020), as paperbacks £12.99 or as e-books £3.99 (2021)