Book Club: A Universe of Dark Matter

The Science History Institute Book Club reads The 4% Universe by Richard Panek.

By Sarah Reisert | May 7, 2019
Drawing of outer space and planets from an advertisement from the Hercules Powder Company

Detail from a 1930 Hercules Powder Company advertisement, "Time, Space, and the Balance Sheet"

Science History Institute

The Science History Institute Book Club now has a Facebook group. If you read along with us at home, you can interact with Institute staff and other fans of books about science and the history of science. Join up and let’s talk!

Greetings from the Science History Institute Book Club. Our most recent book was Richard Panek’s The 4% Universe, which delves into one of the hot topics in science: dark matter.

What is dark matter? Good question: we don’t really know. Wait, what? you might say. But then how do we even know it exists? Well, using what we know about how the universe operates, scientists have realized there must be more matter and energy out there than we can see—a lot more. Dark matter makes up about 27% of our universe; its cousin, dark energy, makes up another 68% give or take. Everything else—all the things we can see or touch, what we once thought made up our entire universe—is only 4% to 5% of the total.

Panek details how scientists figured out dark matter was a thing and the many ways they tried to understand what it is and how it operates. But because the theory behind dark matter is still a work in progress, it could be another few decades before we gain deeper knowledge. In the meantime The 4% Universe offers a good historical overview of the concept of dark matter and what it means for the universe.

There are some things about physics I just can’t wrap my head around. (I’m looking at you, particle physics, relativity, and quantum mechanics!) But I love astronomy and took a few semesters of it in college, so I thought I’d be in good shape here. I was partially right (I understood all the terms Panek used) and partially wrong (I couldn’t decipher what he was trying to tell me, even though he used words I know). I felt a little better when a member of our group with a physics degree revealed she had trouble understanding the book. Other members had less trouble with the material, and many praised the clarity of his writing.

The 4% Universe doesn’t include any graphs, charts, or photographs, a decision that got a mixed response from the group: some readers said these elements weren’t necessary because Panek did a thorough job describing scientific concepts; others said visual aids are always helpful, particularly in nonfiction books. The conversation reminded me of an anecdote I’d heard about Stephen Hawking’s A Brief History of Time: his publishers warned him that every mathematical equation he included would halve the book’s sales, so he included only one. Maybe Panek’s publishers agreed.

We also talked about Vera Rubin and the obstacles women in science faced in the 1960s and 1970s, when Rubin was at the height of her career. She studied the rotation of galaxies and realized that they need a lot more matter to rotate as fast as they do and not fly apart. She theorized that some kind of unseen matter must be holding them together—dark matter. Early in Rubin’s career, though, teachers had encouraged her to follow a more “feminine” pursuit—painting—instead of astronomy. She couldn’t attend lectures at her husband’s university because wives weren’t allowed. She was the first woman granted access to observe at Caltech’s Palomar Observatory but arrived to find only a men’s bathroom. Rubin responded by cutting a piece of paper into the shape of a skirt and attaching it to the stick figure on the bathroom door. “Look,” she said, “now you have a ladies’ room.”

Today more male scientists get federal grant money than female scientists. Studies have repeatedly and consistently shown that work associated with a woman’s name is not rated as well as work of equal quality associated with a man’s name. A study by the American Association of University Women found “eight key research findings that point to environmental and social barriers—including stereotypes, gender bias, and the climate of science and engineering departments in colleges and universities—that continue to block women’s progress in STEM.” So on the plus side female scientists now have bathrooms; on the negative side a woman’s very name counts against her work in the eyes of reviewers. We still have quite a way to go.

Here are a few more of our points of discussion:

1. Did you have a favorite scientist in this book? “Big Dave” Schramm? Michael “Can’t we be exuberant for a while?” Turner? Vera Rubin, hanging out her bedroom window as a child watching the stars? Someone else?

2. Panek talks about a cycle of theory and observation: “Copernicus’s heliocentric theory anticipated Galileo’s observations of Jupiter and Venus, which inspired Newton’s theory of universal gravitation, which anticipated more than two centuries’ worth of moons, planets, and stars, which inspired Einstein’s theory of general relativity, which anticipated the observations of the expanding universe, which inspired the Big Bang theory, which anticipated the revival of Einstein’s theoretical cosmological constant, which anticipated the observations of Type Ia supernovae, which inspired . . . ,” and so on. Use this as a jumping-off point to talk a little about the interplay between theory and observation.

3. Despite the High-Z supernova search team deliberately trying to avoid an arrangement where postdocs do all the work and the lead astronomer gets all the credit, awards and prizes often go to the big guns. For example, a Nobel Prize can be awarded to only three people, despite the dozens or even hundreds of scientists working on a given problem. As the nature of scientific discovery has changed, should these prizes also change? In what ways?

Our next book club topic coincides with an important anniversary in the history of science: the 50th anniversary of the moon landing! We’ve picked two (yes, two!) books on this topic: Shoot for the Moon: The Space Race and the Extraordinary Voyage of Apollo 11 by James Donovan and the graphic novel T-Minus: The Race to the Moon by Jim Ottaviani. Read one or both, and we’ll talk about them in our Facebook group in mid-June.