by Kit Chapman
Christian was in the office because she had dared to switch majors. She had initially signed up for applied art, but one of the required courses had been home economics chemistry, a subject she had never encountered before. The professor, Nellie Naylor, was an inspiration. ‘I found myself more interested in chemistry than anything I had ever studied,’ she later recalled in The Transuranium People. ‘[The lecturer] made it all seem so beautifully logical as well as relevant to a host of everyday problems.’ Screw home economics: Darleane Christian was going to be a chemist.
Her counsellor disagreed and had summoned Christian to set her straight. ‘Do you really think chemistry is a suitable profession for a woman?’
Christian smiled sweetly. ‘I’m quite sure it is,’ she replied.
Christian had graduated from her high school with the highest grades the institution had ever recorded. In her spare time, she had breezed through advanced mathematics and trigonometry correspondence courses, taken up the saxophone and played basketball for her school (which, given her height disadvantage, was a feat unto itself). Her heroine was Marie Curie, a scientist who had discovered elements, explored radioactivity and won two Nobel Prizes all while raising two children. Darleane Christian was a real-life Lisa Simpson, with the cartoon character’s same stubborn streak and tenacity. If Curie could do it, why couldn’t she?
The counsellor was prepared for Christian’s attitude and played a trump card: even if Christian made it as a chemist, there was no way she’d find a job in the chemical industry. She’d end up a chemistry teacher – and female teachers were expected to resign if they married. Christian was far too interested in boys to end up a spinster. The counsellor expected her to give up and stick to art.
Christian didn’t flinch. ‘So,’ she decided with a defiant grin, ‘I’ll just never teach. I’m going to follow Marie Curie’s model. I’ll marry if I want and I’ll have children if I choose.’
The counsellor had run out of objections. That was fine for Christian: she wasn’t asking permission anyway. For the rest of her undergraduate course she was usually the only woman in the chemistry lectures, even though the Second World War had plucked a generation of fighting men from their classes. She excelled, of course.
Short on money, Christian paid her way through college working summers as a waitress and then as a bank teller. By 1947 she was sick of doing boring summer jobs and applied for a research position at ‘Little Ankeny’, the Ames Laboratory at Iowa State. This was a clutch of small, single-storey buildings on the edge of campus, and college legends spoke about secret experiments and strange, late-night flashes of light sparking from inside. The stories were true: Ames had been another of the Manhattan Project’s satellites and was focused on improving uranium production. Christian applied and, like Al Ghiorso before her, got a job building Geiger counters. Unlike Ghiorso, Christian loved it – she was being paid $170 a month for something she’d have happily done for nothing.
Figure 7 Darleane Christian at the Ames Laboratory, 1950.
At Ames, barriers were thrown in her career path – barriers that seemed conveniently forgotten for men. Security passes, for example, required a person to have three initials. Christian had no middle name. But if the lab workers thought that was going to deter her, they didn’t know who they were dealing with. With a shrug, she put ‘DXC’ on the form and told them she now wanted to be called Darleane Xanthasia. Nobody was dumb enough to argue.
Christian was soon heading to be a nuclear chemist. But the roadblocks only became harder. Two years into her course, her father died. Despite her grief, she plucked up the composure to head to the university and ask if she could be excused from the next day’s quantum chemistry exam to arrange the funeral. Her professor – in an act of cruelty masked as compassion – forced her to take the test on the spot. Tears in her eyes and mind elsewhere, Christian still got a B.
Without her father’s income, Christian’s family were destitute. Their home was lost and possessions auctioned. Christian was the only breadwinner in the family and arranged for her mother and younger brother to live with her on campus. After graduation she started to complete her doctorate but found that her cramped quarters weren’t ideal for study. Instead, she spent time each evening with Marvin Hoffman, a man who had exactly what a woman like Darleane was looking for: late-night access to a synchrotron for photonuclear-induced Szilard–Chalmers reactions. In December 1951 she finished her PhD and married him.
The roadblocks continued. Now Darleane Hoffman, the young chemist worked for a time at Oak Ridge, before moving to Los Alamos to lead a nuclear chemistry group. On arrival, the staff at the personnel office looked at her with barely hidden contempt. ‘There must be some misunderstanding,’ she was told. ‘We don’t hire women in that division.’ It took a month of waiting around trying to sort out the paperwork before she ran into her supposed supervisor at a cocktail party. The supervisor immediately contacted the personnel office and got things straightened out. Yet still the roadblocks continued. Now at least acknowledged as being supposed to be at Los Alamos, Hoffman’s clearance was mysteriously lost. After another three months on the sidelines, Hoffman grew tired of waiting and called in the FBI. The ‘lost’ credentials turned up almost immediately.
While Hoffman had been trapped in bureaucratic hell, she missed out on the discovery of two elements. Los Alamos had been the first stop in the US for the filters collected from the Ivy Mike hydrogen bomb test (see Chapter 6). By the time Hoffman was cleared, the filters had been analysed and passed on to other labs – which had resulted in the discovery of elements 99 and 100. It was, for Hoffman, an unforgivable slight that had cost her a place in history. ‘I missed being a discoverer of einsteinium and fermium … while I was sitting in a small apartment in Los Alamos raging against the system,’ she later wrote in in The Transuranium People. ‘I will never again trust personnel offices, not just for saying “we don’t hire women in that division”, which was untrue, but for their general insensitivity, incompetence and bias.’
It would be a lie to say it got easier. Jacklyn Gates remembers Hoffman telling her of times she walked into machine shops where Playboy pin-ups had been left on walls deliberately to intimidate her; of casual sexism from people who assumed she was a secretary; of times she was underestimated because she was just a ‘sweet little lady’. Anyone who thought Darleane Hoffman would be a pushover or would back down soon thought twice. Thanks to her, any notions the Los Alamos personnel office had about women in science were quickly dispelled.
Hoffman’s abilities matched her iron will, silencing critics with some of the most brilliant chemistry of the twentieth century. She became an expert in fission, in new isotopes and in how bacteria interact with metals. She would also become a tireless activist for women in science (although her greatest pleasure was winning awards as a chemist, not just because she was a woman). Ask any of the latest generation of US nuclear chemists working today, male or female, who helped them the most and Darleane Hoffman’s name will come up time and time again. For a decade, despite being 13 years his junior, Hoffman’s picture was hung on Glenn Seaborg’s office wall as a source of inspiration (eventually he replaced it, no doubt to Helen Seaborg’s annoyance, with a picture of him meeting the movie star Ann-Margret).
By 1971 Hoffman had 20 years of chemistry experience behind her, and was a brilliant researcher who wore distinctive cat-eye glasses as she oversaw some of the most painstaking research in nuclear chemistry. By this time, the superheavy element searches were raging across the world. Hoffman set her sights far lower: she just wanted to prove that there was something from when the Earth formed that was heavier than uranium. For this, the obvious target was plutonium-244 – the isotope first detected by Los Alamos after the Ivy Mike tests, with a half-life of 80 million years.
Hoffman’s plan of attack was simple. She would obtain a sample of an ore that had an unusually high concentration of heavy elements and test it. Searching across America, her team foun
d a pre-Cambrian bastnäsite, a 4.6 million-year-old lump of rock, being processed by the Molybdenum Corporation of America to make magnets, lasers and parts for self-cleaning ovens. The rock was being mined for cerium oxide, as it had 500,000 times the normal quantities of CeO2 than normally found on Earth.
A diligent chemist, Hoffman knew that if plutonium was going to be anywhere, the bastnäsite was it. Better still, the way the CeO2 was extracted wouldn’t remove any of the precious plutonium. She called up the Molybdenum Corporation and asked if she could have all their waste material. The company were happy to oblige. Hoffman partnered with another researcher, Francine Lawrence, and began the delicate task of processing the sample. This was painstaking, careful chemistry – as tricky as anything Stanley Thompson had pulled off during the Manhattan Project.
Once finished, Hoffman shipped the sample off to General Electric in Schenectady, New York, where a friend had one of the most sensitive mass spectrometers (a piece of kit that weighs the different components of a sample) in the world. If plutonium was there, they would find it.
That night, Hoffman went to the open-air opera in Santa Fe. She cast her eye to the cosmos, up to the glittering sparkle of alien suns, each furiously creating elements and ready to scatter them across the worlds. ‘As I looked out at the bright stars in the clear New Mexico sky behind the stage,’ she later wrote in The Transuranium People, ‘I somehow had the feeling that this time we would find remnants of the elusive Pu-244 remaining from the last nucleosynethesis of heavy elements in our galaxy, some five billion years ago.’
She was right. When she returned to the lab the next day, the results sent back from New York were unmistakable. The sample contained 8 femtograms of plutonium – a sample that would be invisible under even the best microscopes of the time. It was a dot of pure metal that dated from the very origins of our planet, arriving from a supernova explosion somewhere near our solar system and caught in the moment a cloud of gases coalesced and cooled to create our home.
The small-town Iowa girl, through skill and smarts, had achieved something her idol Marie Curie would have been proud to claim as her own. She had found the heaviest rock on Earth – and with it, she had touched the origins of us all.4
Perhaps unsurprisingly, after her success Hoffman found herself surrounded by scientists asking why she didn’t follow up her success of detecting natural plutonium for the first time by looking for superheavy elements in nature. Her reply was easy: finding plutonium was difficult enough. Trying to find an element whose atomic number, weight and chemistry could only be guessed at? That was nearly impossible.
Notes
1 This is only the tip of nuclear physics: like a series of Russian dolls, the models become increasingly intricate as you get smaller and smaller. The good news is that this is as complicated as we need to go.
2 The peninsula of stable nuclei doesn’t directly correspond with filled shells, and there are even nuclei with filled proton and neutron shells way off the peninsula (such as tin-100, which has a half-life of about one second). Science is complicated.
3 Grams per gram (so you could find 10-23g of something hidden per 1g sample).
4 It wouldn’t be heavy element science if this weren’t disputed. Later research has been unable to reproduce Hoffman’s achievement, and there are questions over whether her experiment worked at all. There’s also some debate (it’s impossible to be sure) as to whether the plutonium she found was the result of cosmic rays, or really dates to the formation of Earth. It may not be very scientific, but after all she went through, I’m going to give Hoffman the benefit of the doubt.
CHAPTER TWELVE
Life at the Edge of Science
Lab life has rhythms, riding its own beats and twisting in its own revolutions as people come and go. By the 1970s Berkeley Lab had escaped the shadow of anti-Communist sentiment and evolved into an eclectic mix of experiments that had won eight Nobel Prizes. Under Lawrence and McMillan (who finally retired as director in 1972), the house on the hill had become the undisputed king of experimental physics, computing, energy and even cutting-edge biology. HILAC was gone, metamorphosed into Super-HILAC (the team would have preferred something even more powerful, but the Vietnam War meant funds went elsewhere). Now, Al Ghiorso was running the heavy element show, the lab inflected by his own, unique brand of crazy brilliance. In place of Seaborg’s detailed notes, the lab’s logbooks were home to the group leader’s doodles – abstract, vivid, swirling kaleidoscopes of colours reminiscent of Wassily Kandinsky or Henri Matisse. Ghiorso’s voice was regularly heard down the hall, yelling out liberal gripes in protest at how the military had sucked up all the funding for his research.
Below the Berkeley Hills was much the same: a hive of excitement that was alive with a healthy anti-establishment vibe still lingering from the Summer of Love. Music from David Bowie and John Lennon to Roberta Flack and Stevie Wonder filled the streets; and the nearby Oakland Athletics baseball team won the World Series three times. Across the Bay, you could see the old federal prison on Alcatraz, covered in graffiti after a 19-month occupation of the island by Native Americans in protest at the treatment of certain tribes. Beyond, the Golden Gate Bridge was a world-famous landmark. Things around San Francisco were looking up – and being a scientist was finally cool.
The May 1973 issue of Ebony illustrated how science and style mixed. There were glossy photos full of screaming flares and excessive collars, copious adverts for cigarettes and wonderful, lavish typefaces. The cover star of the month was jazz singer Nancy Wilson. The main feature was on Sammy Davis Jr. singing at the White House. But its profile was a man its staff writer described as ‘relatively obscure, unpretentious yet supremely self-confident […] a sort of hip, scientific [individual].’ His name was James Harris. And he was the first African American to discover an element.1
In 1955 Harris had been a 23-year-old army veteran searching for a job. He was born in Waco, Texas, raised by his mother in Oakland, California (his parents divorced when he was young) and had a degree in chemistry from Huston-Tillotson College in Austin, Texas. Harris knew it would be tough walking back into civilian life but hadn’t appreciated just how ingrained racism in science would be, even in the liberal haven of the San Francisco Bay. He was turned down a dozen times by interviewers shocked when he walked in, or by secretaries insistent he was applying to be the janitor, not a skilled chemist. Once, he was given an aptitude test so simple a child could pass it – basic addition and subtraction. Harris had looked at the sheet, passed it back to the secretary and, firmly but politely, told her he didn’t need a job that badly.
Eventually he found work as a radiochemist for a company in the Bay Area, before moving to Berkeley Lab five years later and joining Ghiorso’s team. Harris was an oddity – like Ghiorso, he never had time to get more than a bachelor’s degree – but he was the man chosen to clean the team’s targets, a process that took 22 arduous chemical separations playing with a mere 60mg of radioactive metal. It was the most delicate part of the Berkeley operation. That meant Harris had to be one of the best chemists in the laboratory and, by extension, one of the best in the world.
Another face found in the Berkeley Lab was Glenn Seaborg. The elder statesman of elements had been away in Washington for 15 years and had become of the most eminent scientists in the world – his biography was the longest entry in Who’s Who. During his Washington tenure, he had also completed his transformation into a consummate politician. During one of his final government hearings, a Louisiana senator had tried to corner Seaborg with a coup de grâce: ‘Dr Seaborg, what do you know about plutonium?’ A younger Seaborg might have retorted that he’d discovered it; older and wiser, he merely smiled and promised the senator he knew a little.
Seaborg was content to let Ghiorso run the element hunt. Instead, he fell into a comfortable routine. Each morning, he would walk up and down his infamous steps. Next, he would return to his office, keeping the door open for any student who popped by. If on
e did, Seaborg would immediately drop whatever he was working on – often replies to the president of the United States – to help answer their question. If a student suggested a wild, fantastic idea that Seaborg knew wouldn’t work, he still told them to try it; the experiment would fail, but the student would get a chance to understand why. Once his charges were set for the day, Seaborg would then tour the lab, his head poking through the hallway doors and asking in a gruff Midwest voice: ‘So, what’s new?’ Berkeley Lab’s staff ensured there was always something to tell him.
Often the news came from Matti Nurmia. By now, the Finnish researcher was firmly entrenched as Ghiorso’s closest associate. In 1968 Nurmia had also brought over two students from his group at the University of Helsinki, the wife-and-husband duo Pirkko and Kari Eskola, who took over the painstaking work of analysing the endless stream of data from the laboratory computers. The Finnish outnumbered the Americans three to two. Matti Leino, another Finn who later joined the Berkeley team, joked that it took a Nordic scientist (and later, Japanese scientists) to keep pace with Ghiorso.
Figure 8 The Lawrence Radiation Laboratory, Berkeley team, April 1969. From left to right: Matti Nurmia, James Harris, Kari Eskola, Pirkko Eskola, Al Ghiorso.
As with Darleane Hoffman, Pirkko Eskola found the science culture of the US tainted with sexism. ‘Women scientists were not that common, at least not in the US,’ Nurmia recalls. ‘Mrs Eskola was a lovely blonde lady. She’d encounter all kinds of things. She’d call up another lab about scientific matters, and people would ask “Are you a secretary?” A woman in nuclear science was a rare thing.’ Eskola was more than a match for them. She had no trouble standing up to Ghiorso either; while he constantly wanted to try something new, Eskola usually took the scientific high road and wanted more data. The result was, according to Nurmia, ‘rapid-fire discussions’ between the two, often with Eskola walking away the victor.