"I've always been a visual thinker, as well as being someone who's interested in the technical details," says Jack Challoner, "and I've always appreciated the power of the image to capture the interest, to inspire and to make people curious." The author of 'Seeing Science' explains that his new book provided him with "the opportunity to investigate this a bit more". Rather than "just presenting images", here was an excuse to "think about why they are so important" to enabling our understanding of the world.
Author of more than 40 books aimed at promoting the public understanding of science, Challoner explains that much of his career has involved working intensively with visuals. He says he jumped at the chance to produce 'Seeing Science', which combines and balances both approaches. While the book is clearly a pictorial tour of the history and future of science, it is illuminated throughout by a crisp text that shows why Challoner is one of today's more respected science writers.
The subtitle of his latest is 'The Art of Making the Invisible Visible'. And while this might at first glance sound like a publisher-driven slogan issued from an industry that so underestimates its readership that it can barely produce a book these days without explaining the title, in this case it earns its keep creditably. The use of the word 'art' not only allows Challoner to reinforce the benefit of creative speculations in futurology, but it's also an important acknowledgement of the increasing influence of art in the technology space.
Not only does it put the 'A' in STEAM, but it underlines that there is more to revealing the functions and operations of the world around us than just deploying technology such as microscopes, or producing graphs. Data and numbers, Challoner reminds us, are cognitive challenges until we visually interpret them; in a figurative sense again making the 'invisible visible'.
'Seeing Science'
So much of the world around us is hidden from the naked eye that for centuries one of the most consistent challenges of scientific discovery has been to make 'the invisible visible'. This can be as obvious as presenting small things as bigger using optical instruments, or from a more sophisticated 21st-century standpoint, it can be about how to present data graphically. With its fast shutter speeds and ability to create time-lapse imagery, photography has played a vital role in helping us explore the scientific process, while speculative art can assist the imagination in visualising undiscovered phenomena. How science is presented pictorially is the subject of Jack Challoner's superb new book. 'Seeing Science' is richly illustrated, opening the reader's eyes to how much easier it is to absorb complex ideas – ranging from the mathematical to the microscopic – when we can see them for ourselves.
'Seeing Science' is divided into four sections that cover what Challoner identifies as the cornerstones of visualising the universe we live in. The first is mostly about the technology that allows us insight into the physical world beyond the limitations of our senses. This is where he covers historical scientific instrumentation, before moving along the timeline to photography and electron microscopes, looking beyond the visible spectrum, as well as fields and particles. The second is concerned with data, information and knowledge, examining how we visualise numbers and communicate information. In the second half of the book, he moves on to mathematical models, simulations and computational fluid dynamics as ways of expressing reality. In the fourth section, he analyses the relationship between science and art from the prehistoric to the sci-fi future.
This last section is important to Challoner, not least because of its potential to surprise in a discipline that has all the outward appearances of not being receptive to subjectivity. "At first I thought this section would concentrate on artistic impressions, which tend to be about the distant past or things deep in space that we can understand scientifically, but never really see." Challoner soon arrived at the realisation that "art has another role in science, technology and engineering, which is to have an emotional effect in passing on knowledge or inspiring people. Artistic visualisations can put forward ideas in a way that scientists and engineers can't."
For all the credibility of Challoner's text, his words will inevitably be seen by some as the support act for the images, while it is equally certain that others will skim the captions in favour of admiring the images. It's not something you could blame even the most careful reader for, because 'Seeing Science' is a feast for the eyes, whether you're looking at a Santiago Ramón y Cajal's 19th century 'Drawing of Stained Neurone' or Nasa's 'Digital Astrophotograph of Part of the Hubble Legacy Field'.
On nearly every page there is pictorial confirmation that, when it comes to the broad church that is science, in terms of sheer interest value very little approaches it. In the field of photography, there are plenty of old favourites, including Harold Edgerton and Kim Vandiver's superb shot of a bullet passing through an apple, in which the shutter speed is measured in billionths of a second. There's also the poorly staged 1953 black and white shot of molecular biologists James Crick and Francis Watson looking at a Heath Robinson-esque model of the DNA double helix.
These camera-recorded moments are only part of the story. And where photography using visible light tails off is where other genres of illustration kick in, such as graphics, manuscripts, cartography, drawings and digital artworks. There are also quite a few images related to the area of computational fluid dynamics that add much to the visual appeal of the book: "They're really eye-catching and beautiful," says Challoner. Whether done on a computer or otherwise, these are based on the unsolved Navier-Stokes differential equations that were developed in the first half of the 19th century, "and so to have approximations that can be simulated on a computer and then visualised is a really powerful tool. The images they produce are arresting and intriguing."
Without Challoner's words, 'Seeing Science' would without doubt be an aesthetically pleasing, well-curated guide to how we visually respond to science. With them, the book becomes a valuable explanation of how these scientific pictures came about and what they contribute to our depth of understanding. "I wanted to look at why these images are so powerful and so useful," says the author. This examination extends from the starting point of the aphorism credited to New York Evening Journal editor Arthur Brisbane more than a century ago: "Use a picture. It's worth a thousand words."
While Challoner agrees that images are often easier to commit to memory than words, they don't satisfy the curiosity of the enquiring mind in quite the same way. With 'Seeing Science', it's a good idea to have the best of both worlds: the 160-odd pictures and the thousands of words that go with them.
'Seeing Science' by Jack Challoner is from the MIT Press, £28.
The eyes don't always have it
Human eyes are remarkable, but they have three key limitations that render much of the world around us invisible. The first is that eyes are, by definition, only sensitive to a tiny part of the electromagnetic spectrum. The second is that they can only detect light above a certain level of brightness. Only about six thousand stars are visible to the naked eye although many, many dimmer stars are present. A telescope has an aperture larger than the pupil of the eye, and so has greater light-gathering capability. In 1610, Galileo Galilei was able to see "a host of other stars, which escape the unassisted sight, so numerous as to be almost beyond belief".
The third limitation involves "acuity", the ability to resolve detail. This means that very small things, or things that are very far away, are invisible. One cause of this limitation is diffraction – the way in which light spreads out as a result of its wave nature. Light passing through the pupil spreads out from the pupil's edge, just as water waves spread out when they pass through a gap in a harbor wall. As a result, when it falls on the retina, the light from any point of an object forms a small, blurred disk rather than a sharp point. In the retinal image, the Airy disks of any two points that are very close together will merge, and those two points cannot then be resolved.
Visual acuity also depends on the density of the light-sensitive cells in the retina – just as the resolving power of a digital camera depends upon the number of light-sensitive elements in its image sensor. The total number of light-sensitive cells in the retina is close to 100 million. The visual acuity of the human eye is highest where the cell density is highest, in a small region called the fovea. At the center of the fovea, there are more than 150,000 cells per mm2.
Edited extract from Seeing Science by Jack Challoner, reproduced with permission.
Letters to the editor: volume 17, issue 11
In the December 2022 issue of E&T, readers discuss how we should assess the success of technological progress, the economics of hydropower, and more.