"So much of our understanding about uranium focuses on our fears around it"

Interview: Historian and author Lucy Jane Santos on scientific discoveries, nuclear fission, and her latest book, Chain Reactions: A Hopeful History of Uranium.

Specialising in the late 19th and early 20th century Lucy Jane Santos is a freelance historian and consultant examining the crossroads of health, leisure and beauty with science and technology. Lucy’s debut book was Half Lives: The Unlikely History of Radium (Icon: 2020, Pegasus: 2021) and was shortlisted for the 2021 BSHS Hughes Prize, for books that bring scholarship to new readers by capturing the public imagination while conforming to rigorous standards of academic research. We speak to her about her latest book, Chain Reactions: A Hopeful History of Uranium is out in July in the UK and November in the US.

What drew you to write a history of Uranium?

Partially it was the same impulse as why I wrote the first book – because I kept coming across these really intriguing historical tit bits like adverts for Geiger counters and clothes for ‘uranium hunters’, Elvis Presley being billed as ‘the atomic powered singer,’ and Las Vegas tourists watching bombs exploding from their hotel swimming pools. I just became fascinated with it all. Before I had even finished writing the radium book I was already thinking about the next one.

What is Uranium?

It’s an element that is all around us – it is embedded in the earth’s crust (there are over 200 known minerals that contain uranium) and can even be found in sea water.

When did humans first start using it?

Because it is so abundant and often very visible – many of those uranium minerals are lovely bright oranges and yellows – it is likely that humans have always used it in some form or another. We just don’t know very much about how until around the 18^th century when it was properly identified as one of many components of the mineral pitchblende.

Pitchblende

Can you tell us about Martin Heinrich Klaproth, Eugène-Melchior Péligot and the discovery and naming of the element?

Klaproth was an analytical chemist who was very keen on investigating minerals. In 1789 he analysed pitchblende, a black mineral that was considered rather a nuisance by miners as it usually only appeared when the good stuff – gold, silver, tin – had run out. Klaproth found that it contained a substance that nobody had identified before and reported that he had unearthed a new metallic element, which he named uranium, a name that was a tribute to the discovery of the planet Uranus a few years earlier. However, as it later turned out, what Klaproth actually had was uranium oxide, a compound of uranium and oxygen. It was Eugene Melichot Peligot who isolated the pure element in 1841.

How was Uranium’s link to radioactivity discovered?

In 1895 Wilhelm Roentgen discovered X-rays and the world went rather wild for anything to do with invisible rays. This led to a drive to see whether they existed in nature and Becquerel, who came from a long line of scientists interested in luminescent materials (substances that emit light when hit by sunlight), decided to experiment with samples of uranium placed on photographic plates to see if he could recreate the X-ray effect. Rather unexpectedly he found that uranium was capable of producing images on the plates – even when there was no external light – and identified what became known as the phenomenon of radioactivity. Simply put this means that some minerals naturally emit a penetrating radiation. From there other known elements that had the same property were confirmed and Marie Skłodowska-Curie isolated two brand new radioactive elements – radium and polonium.

One of the things that is most closely linked to uranium in popular imagination is nuclear power. How and why did scientists first understand its nuclear capabilities?

The discovery of radium in particular was a sensation not only for the public (as I focus on in my first book Half Lives: The Unlikely History of Radium) but also for scientists. The early twentieth century was a very exciting period for science in any case – in 1911 the nucleus was discovered, the proton in 1919, the neutron in 1932- fundamentally scientists came to understand the basic structure of the atom. Whilst that was groundbreaking in itself, it was then theorised (and proven true) that neutrons could be used to create new elements, ones that didn’t exist in nature. And added to all that it was discovered that when the heavy and unstable uranium was bombarded with a neutron its nucleus split into two - a process that was given the name fission. These fragments then, in turn, released additional neutrons which were then absorbed by nearby atoms, which then split and released neutrons, and on and on in a chain reaction.

Lise Meitner with Otto Hahn in 1912

Can you tell us about the role of Uranium with regards to the Manhattan Project and the Cold War?

When scientist Lise Meitner first correctly identified and explained the fission process (other scientists thought something else entirely was happening) it was 1938. This was really not a good time to be a Jewish born Austrian living in Berlin and Meitner, was forced to flee the country. She wasn’t the only one and many European scientists had moved to the UK and the US seeking both safety and the ability to continue their work. Whereas previously the scientific community had been used to working collaboratively across countries, the rise of Nazi Germany and the eventual declaration of war caused the shutters to be drawn down. Those exiled scientists who had been working on nuclear projects collaboratively and openly were now worried about what the German’s were doing – one question in particular caused a lot of angst – had they worked out how to use the energy that was released in the chain reaction process to create a uranium bomb?

There were enough scientists on both sides of the Atlantic who thought that this was an entirely feasible scenario and were worried what effect this incredibly powerful weapon would have on the war effort. The Manhattan Project was born out of fear but also the calculation that given enough money, expertise and military support the Allies could beat German scientists. Because Britain was under bombardment it was decided to centre the mission in the US. And it was there, in secret locations and cities, that scientists confirmed how to generate a sustainable chain reaction, developed the processes that could efficiently ‘enrich’ uranium to increase the proportion that would fission, learnt how to bombard uranium with neutrons to ‘breed’ the newly discovered and very dangerous element plutonium, and to build their own atomic bombs.  

What do we get wrong about the history of Uranium?

For me it is that the history of uranium is just about bombs and disasters. I called the book ‘A Hopeful History’ because so much of our relationship with uranium has been about hope – hope for medical treatments, hope for a better world and hope for low carbon energy. So much of our understanding about uranium focuses on our fears around it, whether they are real or imagined, but there is such a rich history beyond that which I really wanted to explore.

What can people expect from Chain Reactions?

People can expect a lot of science of course, but as someone who doesn’t have a scientific background, I put lots of effort into making sure that it is all easily understandable. There is also lots of non-science stuff as well because so much of the book is about how members of the public experienced uranium – from beautiful glassware to the uranium hunting craze of the 1950s to quack medical treatments and the development of nuclear energy.

Do you have an element in mind for your next book?

Actually, my next book is on an entirely different subject – it is a behind the scenes look at the filming of a movie and the complex relationships between its stars and director. It’s my favourite movie, my favourite director, my favourite actress and my favourite actor so it has been an absolute joy to work on this project. I don’t think am meant to say any more information on it yet, but it will be out in early 2026. 

Even with such a different topic on the go I couldn’t leave my beloved elements behind and, along with two friends, have set up The Cosmetica Repository to look at how elements like lead, mercury and arsenic to name a few have been used historically in cosmetics. It is another topic where there is a lot of misunderstanding around the motivations of users, and we are having a great time uncovering new stories.

Lucy Jane Santos is on Substack and can be found on X and on Instagram. Chain Reactions: A Hopeful History of Uranium is out now in the UK.

Back in 2022, Lucy Jane Santos explored the surprising history of science and beauty in the first of HistFest’s History Perspectives series.