3.7 — The Ones Who Were Nearly Left Out

Every field has a set of people whose work is standard and whose names had to be argued back into the record. The pattern is consistent enough to be worth studying on its own: the person doing the observing is separated from the person doing the interpreting, and credit follows the interpretation.

Astronomy

Who worked out what stars are made of?

Cecilia Payne, in a doctoral thesis in 1925, and she was persuaded to say she was probably wrong.

The accepted view was that the sun has roughly the same composition as the Earth — mostly rock-forming elements, with iron prominent. Payne applied new work on how atoms absorb light at high temperature to stellar spectra and found the opposite: the sun is overwhelmingly hydrogen and helium, by a factor of about a million for hydrogen relative to the metals.

Henry Norris Russell, the leading American astronomer, reviewed the thesis and told her the result was "clearly impossible". She added a line saying the hydrogen abundance was almost certainly spurious. Four years later Russell reached the same conclusion by another route, published it, and is often credited with the discovery — although he did acknowledge her.

Her thesis was later described by another astronomer as the most brilliant PhD thesis ever written in astronomy. The fact that stars are mostly hydrogen is the starting point of all stellar physics, nuclear fusion, and the origin of the elements. She spent years at Harvard doing the work of a professor while formally employed as a technical assistant, and became Harvard's first female full professor in 1956.

Who discovered pulsars?

Jocelyn Bell, as a graduate student in 1967, and the Nobel Prize went to her supervisor.

She had spent two years helping build a radio telescope out of poles and wire across four acres, and was then analysing its output — about 30 metres of chart paper per day, by eye. She noticed a small recurring smudge she described as "a bit of scruff", which was easy to dismiss as interference.

She followed it up, found the signal pulsing with extraordinary regularity every 1.337 seconds, and then — the crucial step — found three more, in different parts of the sky. The team had briefly labelled the first source LGM-1, for Little Green Men, since an artificial signal was one hypothesis; four sources in four directions ruled that out. They were neutron stars, spinning several times a second and sweeping a beam past the Earth like a lighthouse.

The 1974 Nobel Prize in Physics went to Antony Hewish and Martin Ryle. Bell Burnell has consistently declined to complain about it, arguing that supervisors do carry responsibility for their students' work. In 2018 she received a $3 million Breakthrough Prize and donated all of it to fund physics scholarships for women, ethnic minority and refugee students.

Who were the Harvard Computers?

A group of women employed from the 1880s at Harvard College Observatory to examine photographic plates of stars, at a fraction of a man's wage, because the work was considered clerical.

They produced some of the most important results in astronomy.

Annie Jump Cannon classified around 350,000 stars by hand and devised the classification scheme — O, B, A, F, G, K, M — that is still used, ordering stars by temperature.

Henrietta Swan Leavitt studied variable stars in the Magellanic Clouds and found that a particular kind, the Cepheids, pulses more slowly the brighter it actually is. That relationship converts an observation into a distance, because comparing true brightness with apparent brightness tells you how far away something is. It is the first rung of the ladder by which every cosmic distance is measured, and Hubble used it to show that other galaxies exist outside our own and that the universe is expanding. Leavitt died in 1921; a Swedish mathematician tried to nominate her for a Nobel Prize in 1925 and discovered she had been dead for four years.

Williamina Fleming had been Edward Pickering's housemaid. The story is that he became exasperated with an assistant and said his maid could do better, then hired her. She discovered the Horsehead Nebula and catalogued over ten thousand stars.

Physics and chemistry

Who proved that the universe distinguishes left from right?

Chien-Shiung Wu, in an experiment she designed and ran in 1956, and the Nobel Prize went to the two theorists who had asked the question.

Physics had assumed parity was conserved: that any process would look equally possible in a mirror image of itself. Tsung-Dao Lee and Chen Ning Yang argued this had never been tested for the weak nuclear force and asked Wu, the leading experimentalist on beta decay, whether it could be.

The experiment was extremely difficult. She had to cool cobalt-60 to within a hundredth of a degree of absolute zero, align the nuclear spins with a magnetic field, and count the direction in which electrons came out. They came out preferentially in one direction. The mirror image of the process does not occur equally. The universe, at the level of the weak force, is not symmetric under reflection.

Lee and Yang received the 1957 Nobel Prize. Wu did not. She had also worked on the Manhattan Project, solving a problem that had stalled the first reactor, and she was the first person to confirm the electron-positron annihilation predicted by Dirac.

Who else has been left off a Nobel Prize?

Enough people that the pattern is structural rather than accidental, and much of it comes from one rule: a Nobel Prize may be shared by at most three people, and cannot be awarded posthumously. Modern science is done by teams of dozens.

Lise Meitner — nuclear fission, in 3.2.

Rosalind Franklin — DNA structure, in 3.3, where the posthumous rule genuinely applies.

Oswald Avery, who showed in 1944 that DNA rather than protein carries genetic information — the result that made the structure worth solving — and was nominated repeatedly without success.

Fred Hoyle, who worked out how the elements heavier than helium are made inside stars. His collaborator William Fowler received the prize; Hoyle did not, and it is generally assumed his public attacks on the Big Bang theory, a term he coined dismissively, did not help.

Nikola Tesla and Thomas Edison were reportedly considered for a shared prize and, according to a persistent story, each refused to share with the other. The story is not well documented, and neither ever received one.

Computing and mathematics

Who were the human computers of the space programme?

Before computer meant a machine, it meant a person who computed, and NASA's predecessor employed hundreds of them — including, from 1943, a segregated unit of Black women mathematicians at Langley known as the West Area Computers.

Katherine Johnson calculated trajectories for the first American in space and for John Glenn's orbital flight. By 1962 the calculations were being done by IBM machines that nobody entirely trusted, and Glenn asked specifically that she check the numbers by hand before he would fly. She worked through the equations over a day and a half and confirmed them. She also worked on the Apollo lunar module rendezvous.

Dorothy Vaughan saw the machines coming, taught herself FORTRAN, taught it to her group, and moved the whole unit into programming rather than letting it be made redundant. Mary Jackson fought a legal process to attend segregated classes and became NASA's first Black female engineer.

Their work was known internally and essentially unknown outside until the book and film Hidden Figures in 2016. Johnson received the Presidential Medal of Freedom in 2015 at 97 and died in 2020 at 101.

Who wrote the software that got Apollo to the moon?

Margaret Hamilton led the team at MIT that wrote the onboard flight software, and she is the reason the phrase software engineering exists — she coined it, partly to get the work taken seriously in a field where it was treated as an afterthought to the hardware.

Her team's most consequential decision was covered in 2.6: the computer was built to handle being overloaded by shedding low-priority work rather than failing. During the Apollo 11 descent it did exactly that, and the landing continued.

She had also identified a specific pre-launch error case — an astronaut selecting the wrong program at the wrong moment — and asked to add a guard against it. She was told astronauts are trained not to make mistakes. She was permitted to add a note to the documentation instead. On Apollo 8, an astronaut made exactly that error, wiping the navigation data, and the ground team spent nine hours reconstructing it from her notes.

Who was Sophie Germain?

A French mathematician who did significant work in number theory and elasticity while being denied any formal education in either.

Germain (1776–1831) taught herself from her father's library during the Revolution. When the École Polytechnique opened she could not enrol, so she obtained lecture notes and submitted work under the name of a former student, Monsieur LeBlanc. Lagrange was impressed enough to ask to meet the author and was startled by what he found; to his credit he became her supporter.

She corresponded with Gauss for years under the same pseudonym on number theory. When Napoleon's army invaded Prussia, she used a family connection to ask a French commander to ensure Gauss's safety — and that is how he learned who LeBlanc was. His reply is worth quoting in substance: he wrote that a woman who overcomes the obstacles placed in her way to master the abstruse parts of mathematics must have the noblest courage and extraordinary talent.

She won the Paris Academy's prize for a mathematical theory of elastic surfaces, the first woman to win it, after three attempts across six years. A prime p such that 2p+1 is also prime is still called a Sophie Germain prime. She died of breast cancer at 55; her death certificate listed her occupation as unmarried property holder, not mathematician.

Medicine and biology

Who was Barbara McClintock?

A geneticist who discovered that genes can move around within a chromosome, was disbelieved for over thirty years, and won the Nobel Prize alone in 1983 at 81.

Working with maize from the 1940s, she noticed patterns of colour in the kernels that could not be explained by genes sitting in fixed positions. She concluded that some genetic elements transpose — physically relocate — and that others switch neighbouring genes on and off, which also implied that gene regulation exists at all.

The reception was cold enough that she stopped publishing her main results in 1953 and circulated them privately. Molecular biology in the 1970s found transposable elements in bacteria and then everywhere, including in humans, where they make up a substantial fraction of the genome. She had been right for three decades in a field that had moved on without her.

Who was John Snow's opposite number — the man who was wrong for the right reasons?

Worth including because being wrong honestly is part of the record too.

Max von Pettenkofer, a distinguished German hygienist, believed cholera required both a germ and a specific soil condition, and rejected Koch's simpler germ explanation. In 1892, at 73, he drank a flask of cholera bacteria in front of witnesses to prove his point.

He survived with mild symptoms, which he took as vindication. He was almost certainly protected by prior exposure or by stomach acidity, and the bacterium was the cause regardless. He was wrong on the science and right on something else — his sanitation work in Munich, driven by his soil theory, cut the city's death rates dramatically because clean water and drainage work whatever your theory says they do.

The pattern

Is there something general here?

Yes, and it is worth naming rather than treating each case as bad luck.

Credit tends to follow whoever states the conclusion, not whoever produced the evidence. Payne had the data and Russell got the credit. Franklin had the photograph and the modellers got the prize. Bell had the signal and Hewish got the Nobel. The person who does the measuring is treated as technical staff and the person who explains it is treated as the scientist, even when the measurement was the hard part.

Credit also follows whoever is already in the room. A supervisor, a professor, a man with a chair. This is not a claim that those people were frauds — most of them did real work, and several of them, like Lagrange and Gauss and Hilbert, actively pushed against the exclusion. It is a claim about where the default lands when nobody is paying attention.

The practical use of knowing this is not indignation about the past. It is that when you are reading about a discovery, the honest question is always: whose hands were on it?

What comes next

That is the end of the lives. The next Part goes back to the world itself — the physics you can point at from where you are sitting, starting with why the sky is the colour it is and why the answer is not "because it reflects the sea".