Cecilia Payne

When you study physics, every great discovery comes attached to a name.  The lessons are almost as much about the history of the field as they are about physics itself.  You learn about Schrodinger's Equation (and cat), Heisenberg's uncertainty principle, Einstein's theory of relativity, Feynman's diagrams, Kepler's laws, Galileo's equations, the Copernican model of the universe, Bohr's model of the atom, Newton's laws, Maxwell's equations, etc.

But you've probably never heard of Cecilia Payne.

I hadn't, until I stumbled across this article about her.  Cecilia was born in Britain in 1900 and came to America to study astronomy at Harvard in 1923.  At the time, it was thought that the sun had roughly the same composition as the Earth, but no one knew the exact proportions of the elements.  Ms. Payne was tasked with determining this and used the latest advances in ionization theory and spectral analysis to do so.  She concluded that the sun is, in fact, mostly hydrogen.

Her conclusion was controversial at the time.  It flew in the face of the accepted wisdom that the sun was mostly made of heavy metals, just like the Earth.  She was shunted into a different field and it was a few years before the work she had done was verified and finally accepted.  She continued to contribute to astronomy in the field of variable stars (stars whose brightness, as seen from the Earth, appears to vary over time) and wrote several books.

As a side note, Cecilia was the first person to earn a PhD in astronomy from Harvard.  Not just the first woman, the first person.

So why don't we learn about her?  Why was she never mentioned in any of my physics classes?  We did an experiment similar to her's in a lab course.  Her name should have been included in that experiment description, but it wasn't.  I thought she might have been discussed in the actual astrophysics course, which I never took.  A scan of my boyfriend's astrophysics text book debunked this theory.  It contains a 20-page section on Cecilia Payne's work.  Her name isn't mentioned once.

I wanted to write about her here, get the word out.  She deserves some recognition.  She should be as famous as Newton, Galileo, or Einstein for discovering such a crucial and fundamental fact about our universe.  But she's not.

Note:  Apparently it is International Women's Day.  I didn't know that when I wrote this post, but it seems fitting.  If you can think of any other women who don't get enough love, let me know and I'll write about them.  This was fun.