Mapping the Heavens: The Radical Scientific Ideas That Reveal the Cosmos is an excellent guide to the many radical discoveries that are remaking our understanding of the cosmos. The author, Priyamvada Natarajan is a theoretical astrophysicist at Yale who maps dark matter by observing how light is bent by “potholes” as it travels from its source to where we see it. These potholes reveal the mysterious dark matter whose effects we can map (Well, Natarajan can map.) even while we don’t have a clue what it is.

There is a poem that I used to include in my syllabus as a history teacher. It’s by Thomas Bailey Aldrich and begins, “My mind lets go a thousand things/Like dates of wars and deaths of kings” and then goes on to recall the very hour the wind shook loose two petals from a flower. I think of it often when reading historical overviews. Authors are always in a double-bind. If they don’t include the thousand things, they will be perceived as unserious, and if they do, they risk losing their readers before they get to the good stuff when those petals start falling. For me, when I read the overviews, I just tell myself, it will get better and it usually does.

The book begins with an extensive overview of the history of cosmology from the earliest observations recorded in cuneiform more as statistical tabulations without any attempt at explanation though the centuries. Natarajan makes some effort to remind readers that cosmological exploration was not isolated to Europe, reminding us of the invention of the compass by the Chinese, the mapping advances from India and the critical role of Arabs in creating the mathematics that formed the foundation for advanced cosmology. She also reminds us that the Flat-Earth Society has been a collection of anti-science cranks since Ptolemy, not Columbus – though not in those words.

One of the central points she makes is that science is provisional and self-correcting. Throughout the history of science, new technologies enable the collection of new data, new data creates new insights and discoveries, and meanwhile old ideas resist change. There is a clash of ideas, sometimes people suggest a middle way, but ultimately, the best data and explanations win out because science chooses what is replicable and empirical even when it is uncomfortable.

It is unfortunate that this overview must come first, but it must because all the rest of the book is built on its foundation, but it is far less exciting and interesting than the meat of the book that beings in the second chapter and then just keeps building. The tone of the writing changes dramatically after the first chapter, becoming more conversational, more engaging and far more fascinating. Natarajan adds lots of interesting information such as Poe presaging Hubble’s discovery of the expanding universe in a poem eighty years before Of course, Poe had no evidence, it was a dream of an idea, but it was true and Hubble confirmed it with science. The expanding universe upends everything, after all literature is full of the constancy of the heavens and Hubble broke it. It makes this science so much more accessible for the general public when she makes this connections with other disciplines like literature and poetry.

I love how Natarajan reveals the humanity of the scientists who shape our worldview. Einstein’s resistance to the expanding universe, his “fudge” as she calls it, a final attempt to hand onto the static universe model in the face of new evidence and his eventual confession he was wrong. It’s kind of reassuring to know that even Einstein hung onto belief over evidence for a while before coming round. Because he did come around. Perhaps those who cling to denial of climate change and evolution will do the same. Maybe not, but the idea that Einstein fudged for a bit makes me feel more optimistic about those who doubt science today. She also describes how Sitter’s wrong explanation while being totally, bizarrely wrong, contained a nugget of an idea that helped jumpstart another direction that led toward the right solution (or at least, since science is provisional, what we believe now is the right solution.) Equally fascinating, it is something so simple as photographic plates that enabled the real breakthroughs in observation that advanced the radical theories we have now come to accept.

Natarajan brings the same enthusiastic passion to revealing the nonlinear push and pull advancements that led to the discovery of black holes, dark matter, background radiation, the accelerating universe and will, I am certain, the discovery of other worlds and other sentient, curious, imaginative and creative beings. Full disclosure: I began volunteering my background computer capacity to SETI back when I had a Apple Mac Classic. But when Natarajan talks about other worlds, she does not mean just habitable planets with sentient life out there somewhere lost in the stars, but also other worlds in the multiverse and whether there could be life where the cosmological parameters necessary for the universe as we know it are different. This is radical stuff, revealing that scientists are some of the wildest and most radical thinkers on the planet.

But isn’t that what science is? Taking what we know, what we can observe and then getting freaky with it? Always presuming of course, the evidence backs it up.

4paws I recommend this book highly. Natarajan has a way of taking theory and all its complexity and explaining it so this non-scientist can easily understand it. She effectively explains the ideas that develop and the historical and technological waves that eventually erode those past explanations and replace them with new constructs, new ideas. She makes the process of interesting, human and fun, with little tidbits of gossipy details that bring revered scientists to life. I have always loved physics, took one astronomy class in college and worked at a planetarium (As an usher, believe me hearing the same presentation 6 times a weekend for 3 months ingrains those particular ideas forever,) so I am not intimidated by science, but I have no real science background, no expertise, and yet never felt overwhelmed by the science.

I like her holistic approach, combining literature and cultural information as ways of showing how radical some of these new concepts are. There are wonderful illustrations. It took me a few weeks to read this, but that is generally how I read nonfiction. I read until I come to a concept I need to think about and internalize and switch to some fiction, coming back when I have chewed it over a bit and am ready to learn something new. My mind still lets go a thousand things, but this book is full of falling petals and they are beautiful in their mystery and magnificence.

To see just how engaging Natarajan is, here she is giving a short talk about her work.

Mapping the Heavens will be released on April 26th. I received an electronic advance copy from the publisher via NetGalley.