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Author: H. J. McCracken

Looking into (the) COSMOS with the James Webb Space Telescope

Looking into (the) COSMOS with the James Webb Space Telescope

With the imminent launch of JWST — we hope! — I am resurfacing an article I wrote earlier this year which appeared in a different form on the IAP front page. Next year I will be giving a public conference about this which will be streamed live.

Astronomers learned to read the patterns of stars in the starry night skies as clues to the shape of our own Milky Way. Powerful telescopes soon showed that galaxies themselves were spread out across the sky in a pattern that holds profound clues to the nature and eventual fate of the Universe itself. This is the history of astronomy: with each new instrument, scientists take a step towards a better understanding of our Universe. Very soon, using the James Webb Space Telescope (JWST), an international team of astronomers — my friends in the COSMOS project — will map out a vast unexplored region of the very distant Universe. A key prediction of current theories of the formation of the Universe is that stars and galaxies form hot ionised bubbles of gas in the early Universe. With JWST we will see for the first time the imprint of these bubbles on the large-scale distribution of the very first stars and galaxies. They will also help us to understand how mysterious dark matter helps galaxies to form at the earliest times.

Bubbles in the early Universe (from A. Loeb)

Over the past three decades, the Hubble Space Telescope has opened up vistas of the distant Universe only dimly glimpsed by ground-based observatories. However, charting out how galaxies are linked together across the sky seemed at first like an impossible task for Hubble. The telescope’s cameras can only see a tiny part of the sky in each exposure. But a team of astronomers ambitiously used Hubble to survey a region of the sky larger than the full moon — now known as the COSMOS field — making it the latest ever contiguous patch of the sky covered by Hubble. Since then, thousands of scientific papers have delved deep into the COSMOS field, drawing a detailed picture of how galaxies, dark matter, gas, and dust interact on large scales and how they have changed over cosmic time. Since those first Hubble observations, COSMOS has been covered by every major telescope and this data has been shared in a remarkably open and productive collaboration between all the world’s astronomers.

The original COSMOS Advanced Camera for Surveys HST mosaic

The COSMOS catalogues have become an essential reference point for the evolution of galaxies over cosmic time and an invaluable starting point to ask any new questions about the Universe. The papers describing them are among the most highly cited in astronomy. COSMOS catalogues have also played a crucial role in preparing for Esa’s Euclid mission.

Of course, astronomers would always like to see further. Data from COSMOS has hinted at another Universe of very distant, massive galaxies just out of reach of current surveys. The finite speed of light is a wonderful time-machine which means that these most distant objects lie, in fact, at the very beginnings of the Universe. But the expansion of the Universe means their light becomes redder and redder as it speeds towards us. To see so very far back, one needs a not only a telescope with a mirror large enough to collect these lonely photons arriving from the edge of the Universe — but also one sensitive to the infrared light bringing messages from these distant galaxies. An even greater challenge is that every ordinary object also emits infrared photons; these would drown out the faint signal from such distant galaxies. To detect this ancient light, the telescope must be cooled to a few degrees above absolute zero and placed far from terrestrial sources. The ten-billion-dollar James Webb Space Telescope (JWST), with its golden 6.5 meter foldable mirror, due to be launched and sent to one of the coldest places in the solar system, is just such a telescope. It is optimised for the study of these faint distant objects. A single exposure from JWST will see deeper than the decade-long ground-based infrared surveys that we in the COSMOS team have been carrying out.

Let’s hope that it will look like this in a few months…

JWST is a remarkable instrument, perhaps the most sensitive telescope ever constructed. Its cameras can record light from objects infinitely fainter than anything we have ever observed before. But where do you point such a beautiful and sensitive machine if it is looking deep into a country that no-one has ever visited before? The best thing to do, right at the start, is to survey a wide swath of this new territory to guide future scientist-explorers. But once again, such a survey seemed an impossible task with the tiny field-of-view of the JWST cameras. Nevertheless, we proposed a highly ambitious program — now called COSMOS-Web — to cover one third of the COSMOS field with JWST’s infrared and near-infrared cameras. Such a survey would require more than 200 hours of observations, an enormous amount for the highly competitive first year of Webb’s operations. Astronomers around the world requested more than four times the amount of time than were actually available. The results of this competition were announced earlier this year: the COSMOS-Web proposal was accepted, making it the largest survey to be carried out during the first year of JWST’s operations. We call it COSMOS-Web because it will map out the web of large-scale-structure of the Universe at the earliest epochs.

Simulated image of the JWST-COSMOS field

Our program comprises 206 hours with JWST’s NIRCAM instrument and 80 hours taken simultaneously with the longer-wavelength MIRI camera. Together, in COSMOS-Web these instrument will produce a new map of the very distant Universe. All data will be public. The new data will contain tens of thousands of very faint and distant galaxies, signposts for follow-up observations with JWST’s other very sensitive instruments. Astronomers will see, for the first time, the structure and form of galaxies in the early universe. And we will see, we hope, things we do not expect to see. Over the years observations in COSMOS has turned up countless interesting and peculiar objects and I am certain JWST observations will continue this tradition!

Images in the 21st century: some thoughts on Andre Rouillé’s: “La photo numerique, une force neo-libérale”

Images in the 21st century: some thoughts on Andre Rouillé’s: “La photo numerique, une force neo-libérale”

I recently read an excellent book about photography in the 21st century, Andre Rouillé’s ”La photo numerique, une force neo-libérale”, published by editions “L’échappée” (who are publishing many interesting books about society and technology). It is probably the most lucid text about modern images I’ve read so far: to me, it describes accurately the current state of affairs. Most classic texts about photographic theory (Sontag, Barthes) have been hopelessly outdated by the arrival of the internet and the profusion of digital images. But this one is right up-to-date (published last year) and is the clearest look so far at the role of images in our modern world. The scope of the book is large: not only does it describe how new technology has changed image-making, but how digital images have become essential to the modern economy.

Let’s start by considering a definition of terms. In English, to describe the two ways we have of making images there is ”analogue” and ”digital” but Rouillé prefers the terms photo-argentique (”argentique” is silver) and photo-digital. This emphasizes that they are really different in kind and nature. Analogue images are fixed and immutable, digital images are constantly changing and are defined by computer code and digits. And most, importantly of all, they can be transmitted instantly anywhere around the world and effortlessly duplicated.

This is about where we are now.

Now, consider how images are captured using with film photography (I’m paraphrasing Rouillé here; he is obviously thinking about rangefinder cameras): one looks through a viewfinder and one decides where to put the frame around an object in the physical world. Now think about capturing digital images with a smartphone, because that is how most digital images are created: one looks at a screen on a rectangular object held at arm’s length. The whole body is involved, not just the eye. The notion of the frame enclosing the physical world has disappeared, and in deciding to frame the photograph one moves the arm and not the head. In the first case, you see the world and not the image; in the second, you see the image and not the world. With a smartphone, it is easy to take multiple images, but you can’t always see the screen in bright light. The result, in the second case, is a profusion of images which do not conform to the conventional idea of photography as a document and an accurate representation of the world. This leads, naturally, to a new aesthetic, one in which crucially images are not at all intended to be a faithful reproduction of reality. The usage of photography today is clearly very different from it was in the 20th century, and by way of example he cites the examples of certain 21st century Magnum photographers whose images turned out to be a less than faithful representation of reality.

So the point to be understood is not at all simply a response to the tired ”film versus digital” question, which after reading the book really seems to me to be missing the point. One can certainly use a digital camera (and here I mean I camera, not a smartphone) in the same way as a film camera, carefully setting the shutter speed, aperture, framing the subject, just as you can also use a film camera like a digital camera — he cites Gary Winogrand as someone who did just that, who took film photographs ”in a digital way”. But today, almost all images are created with smartphones, and these multitudes of images are destined to be shared and distributed on social networks. The way in which these images are captured, and the malleable nature of the object used to take them (a smartphone is no more a camera than it is a telephone, a notebook or a record-player) lead to this radically new aesthetic. I think this is quite different from ”snapshot photography” from the start of the 20th century when the first small portable film cameras appeared; those images were never generated in such large quantities and neither were they circulated so widely around the world.

In the second part of his book, he underlines how important digital images have become for the enormous corporations that have become an integral part of our lives. These digital images created in such great quantities have become an enormous source of wealth for these industries — but not, of course, for those who create the images. These images contain all the attributes of the neoliberal world: instantaneous, constantly changing form and present everywhere. Digital images have become crucial in maintaining the economy of surveillance capitalism.

Reading Don DeLlio’s “The Silence “

Reading Don DeLlio’s “The Silence “

I’ve been reading DeLillo’s books for a long time now. The first time I heard his name was when I struck up a conversation with a man on a train in England at the end of the 1980s. He told me that I should really read DeLillo. But it was not until I was a summer student in New Mexico in 1991 that I came across White Nose and its ”airborne toxic event”. And then Underworld when it was published in 1997. I remember carrying around that heavy brick of a book with a photograph of the World Trade Center in the foggy background and St. Marks’ church in the foreground. There was a tiny bird high the photograph, superposed on the towers, that looks to us now like an airplane. DeLillo to me has always been a constant steady background presence. He has always been writing about how conspiracy and terror have such a large place in our contemporary consciousness. So when on one of my walks around town I saw his new book The Silence on the shelves at Shakespeare and Co. I immediately bought it. DeLillo finished this book just before our ”current situation” started.

It is a very slim volume, not more than 100 pages set in a mono-spaced font like it was bashed out on a typewriter. The events in the book take place over the space of a few hours. There’s a catastrophic event but the consequences are not an explosion or widespread destruction. Instead, almost every electronic device stops working. Screens turn dark. And here the event is not seen from the perspective of governments or nations but simply that of a few friends gathered around to watch a football game on TV; there’s a faint echo of the magnificent stadium scene at the start of Underworld. This time, however, people are at home.

DeLillo offers no clear explanations. Perhaps it’s a coronal mass ejection. They’re called ”Carrington Events” after the 19th century scientist who realised what was electrocuting telegraph operators around the world and lighting up the night sky was a big blob of charged particles coming in from the sun. Such an event would have had minimal impact 150 years ago, but today of course it would be catastrophic. Satellites observing the sun would give us a few minutes warning but there would be not much else we could do other than save the files and close the applications. But in DeLillo’s book there are hints that it’s not a natural event.

This is what the silence looks like now

You see, he is not really interested in explaining what happened. His question: what would we do if the screens went dark? What would happen to human consciousness when the current stops flowing? This being a DeLillo novel our friends speak in a complicated stream-of-consciousness diction comprising waves of technical language and terms. Sentences are pared down to a string of nouns. Almost all events take place in a single room; he’s not interested in outside. But what’s happening outside? “You don’t want to know,” a character informs us. One of our friends happens to be an Einstein scholar, a convenient person to have around in an an event like this in a DeLillo novel. And at one point, an uncanny prophecy:

“What comes next?” Tessa says. “It was always at the edges of our perception. Power out, technology slipping away, one aspect, then another. We’ve seen it happening repeatedly, this country and elsewhere […] But remaining fresh in every memory, virus, plague, the march through airport terminals, the face masks, the city streets emptied out. […] Are we an experiment that happens to be falling apart, a scheme set in motion by forces outside our reckoning? This is not the first time that these questions have been asked. Scientists have said things, written things, physicists, philosophers.”

Since Underworld DeLillo’s focus has narrowed right dow. There is no sweep of event, and the voices speaking are only echoing sounds that we have heard before. There’s no resolution, of course. We leave the book still waiting for the TVs to come back on again and for the smartphone screens to light up. And we start to imagine, just a little, what life without these devices might be like.

Bob Giraud’s Le Vin des rues and Patrick Cloux’s Au grand comptoir des halles

Bob Giraud’s Le Vin des rues and Patrick Cloux’s Au grand comptoir des halles

There is a certain segment of time and space here in Paris that fascinates me. It’s that period just after the second world war. Now, a few months ago, just before the portcullis gates swung down (on st. Patrick’s day of all days) I bought Robert Giraud’s Le Vin des rues. A few weeks before that, I discovered by chance the “Librairie Le Piéton de Paris” and following the excellent recommendations of the shop’s owner I bought Patrick Cloux’s “Au grand comptoir des halles“. Over the next few weeks of the lock-down I read both books very closely. They both describe postwar Paris lucidly and entertainingly.

Les halles in the 1960s (Robert Doisneau)

The back-story is well known: for centuries Les Halles was the beating heart of Paris with an enormous market which attracted vast crowds at all times of the day and night. It was at Les Halles that food and produce was bought and sold for all of France. Eventually the narrow streets proved too limiting for the endless deliveries and in the 1970s the wrought-iron 19th century marché was destroyed and operations were moved to a more modern and convenient location at Rungis. The destruction was filmed and photographed; a quick tour on YouTube and you’ll find it all. As well as the above-ground wrought-iron market halls, Les Halles contained enormous subterranean cellars and by the time all that was excavated and removed an enormous hole was left gaping at the centre of Paris, the famous trou des halles.

For quite a few years nobody quite new what to fill it with. There was even a western adventure movie about Custer’s last stand made featuring the hole and surrounding wreckage. Well, of course later there would be a underground railway exchange for the new rapid train nework (the RER) but what else? A shopping centre, Forum des Halles, which is universally unloved. Meanwhile, the parking lot where the produce trucks idled was transformed into the Centre Pompidou. To a person walking around Les Halles today there is almost no trace of the past life. The ouside of the shopping centre looks a little better than it did when I arrived in Paris; it is now covered by the ‘canopée’. In an interesting bit of architectural short-shortsightedness for a city with Paris’ climate the canopé is not actually waterproof. There is at least much more space there than there was before; it is is now open on both sides.

These details you could have found on the interwebs. What Cloux’s book aims to bring back are the people, the conversations, the circumstances, something that is lost in a bare rendering of facts. It is wonderfully evocative. I’ve already written about Jack Yonnet. Girard and Yonnet, togethether with the humanist photographer Robert Doisneau, are probably amongst the better-known characters from that period. But there are many others in there too. There is Claude Signolle, an expert on the occult. Signolle meets a shady character, a man claiming to be practising witchcraft, who shows him the book that he uses to make sure his incantations work. It is one of Signolle’s own books!

Reading Giraud’s Le Vin des rues just after Cloux’s book I understood why this text was so important as a description of that epoch. Reading Giraud is like listening to him talking to you in the Parisian argot of the 1950s (which is not always easy to follow). A simple as a conversation, colloquial, slangy. You could indeed imagine him in front of you on the other side of the bar with a glass of wine in his hand. Giruad describes how hard life was in Paris in the early 1950s and all the characters he met during his walks across the capital. He must have known every homeless person in the centre of Paris, all the people on the fringes of society that polite people would hurry past. It was Giraud who introduced these people to Doisneau who then photographed them with such success.

Robert Giraud, 1950 (Robert Doisneau)

Everybody in Giraud’s book is trying to turn a trick to stay alive. There is the man, for example, who lives in a tiny narrow apartment on the roof and who catches pigeons to sell to fancy restaurants, telling the buyers that they were were caught on country estates. Similarly, once the tourist boats have left, a group of shady characters make night trips onto the Seine to catch fish with explosives which are then brought right to les halles to sell. The there’s the blind girl Girarud helps by collecting cigarette butts for her which she sells on to another character who reassembles them into full cigarettes. Then there is a Giraud himself, who hangs around les Halles at midnight because that’s the best time to look for work, they always need a helping hand unloading the produce trucks and it’s good money, even if you have to work straight until the dawn. (Both he and Yonnet were casually brave during the war. Yonnet led groups of men around Paris into buildings where they would set up clandestine radio antennae to broadcast information to the resistance. An incredibly dangerous activity in occupied Paris and Yonnet had to kill one of his own men who was on the point of betraying them all the the Nazis. Giraud only escaped his Nazi death-sentence when the town where he was being held was liberated by the resistance; he went on to edit a newspaper for them.)

The end: le trou des halles

The worlds that Giraud and Cloux and Yonnet describe are a vast distance from the established literature of the time, even if the you could walk in less than fifteen minutes from Giraud’s bars in the rue de Buci and rue de Seine to the Boulevard St. Germain. I don’t know if Cloux’s book will be ever be translated into English. it’s a dense, lyrical text that took me long enough to read. It felt strange to read these books and to know that, while I was reading them, not a single bar or cafe was open anywhere in Paris.