Today, we ask what the sun's made of. The University of Houston's College of Engineering
presents this series about the machines that make our civilization
run, and the people whose ingenuity created them.
Ray Bradbury's lyrical short story, "The Golden Apples of the Sun"
imagines a research spacecraft, passing through the fringe of the sun -- close enough to
scoop up a sample of its substance. He takes his title from a stanza by Yeats,
I will find out where she has gone
And kiss her lips and take her hands;
And walk among the dappled grass,
And pluck till time and times are done
The silver apples of the moon,
The golden apples of the sun.
What indeed would be the composition of those golden apples; what is the sun made of?
That question soon formed in the mind of young Cecilia Payne, after she'd gone to
Cambridge University in 1919. Payne was brilliant, and she had to both smart and
tough in that male bastion. Earnest Rutherford bullied her and role-modeled rudeness
among his male students. But Payne had aces up her sleeve. She was powerfully
curiosity-driven and self-assured.
Although the quiet Quaker astrophysicist Arthur Eddington encouraged her, graduate
study was then out of the question for a woman at Cambridge. So she went to America,
to Harvard, to study with Harlow Shapely who was studying the sun's composition.
Historians David Bodanis and Owen Gingerich both tell her story -- how the common
wisdom then said that the sun, like any other star, was largely iron. That was what
spectroscope lines appeared to be telling them. But reading the spectroscope lines was
a lot like trying to read words without spaces. The word notable, for example,
might in reality be no table, or not able. Others were reading what
they expected to read in spectrographs.
Cecilia Payne realized that spectrography revealed a sun made of largely of hydrogen
with some helium, not iron. It would eventually become clear that the sun, owing to
its immense mass was a great fusion reactor constantly generating energy. It was not
at all molten iron, cooling down.
In 1925, she finished one of the great doctoral theses ever written. The Chairman of
Physics wouldn't approve her thesis for a physics PhD, but he agreed to sign it for
another department. In a strange academic arabesque, they called it an astronomy PhD,
thus creating a de facto Harvard astronomy department.
Payne then worked in astronomy at Harvard without a position for eleven years, then
finally gave her the title astronomer. She became Harvard's first female tenured
professor in 1956 and later, the first woman department chair. Three years before
she was tenured, Bradbury published his short story. Of course we then knew what
the sun was made of.
We knew that it was far stranger than a cooling iron lump. And the reason we knew was
because Cecilia Payne's unwavering patience and curiosity had been able to
... pluck till time and times are done, ...
The golden apples of the sun.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
Cecilia Payne married Russian astronomer Sergei I. Gaposchkin in 1935 and was known at
Harvard as Mrs. G. thereafter. Owen Gingerich's fine biographical article about her
may be read online at:
Cecilia Payne.
D. Bodanis, E=mc2: A Biography of the World's Most Famous Equation. (New York: Walker and Co., 2000): Chapter 14.
Other Payne-Gaposchkin online articles:
Wikipedia article on Cecilia Payne.
Carleton College article on CeciliaPayne.
Click here to read
Bradbury's The Golden Apples of the Sun online.
My thanks to listener David Bergt for suggesting Cecilia Payne as a subject.
Below: period images of a spectroscope and the image produced by it, from W. J. Rolfe
and J. A. Gillet, A Handbook of Natural Philosophy. (Boston: Woolworth, Ainsworth, & Co., 1868).
The Engines of Our Ingenuity is
Copyright © 1988-2006 by John H.
Lienhard.