The key ideas

Astrophysics for People in a Hurry

Neil deGrasse Tyson, 2017

The whole universe once fit inside a space smaller than the period at the end of this sentence. So why is anything left in it at all? With humor and without a single formula, Neil deGrasse Tyson takes you from the Big Bang to dark matter and shows you honestly where knowledge ends and mystery begins.

Who it is for

For anyone curious about space who has no time for textbooks: from the first second of the universe to dark energy in a single subway ride.

The universe is under no obligation to make sense to you.

What the book is about

The book opens with a sentence that is hard to imagine. Nearly fourteen billion years ago, all the space, all the matter and all the energy of the known universe fit inside a volume less than one trillionth the size of the period that ends this sentence.

Neil deGrasse Tyson wrote this book for people in a hurry: twelve short chapters gathered from his magazine essays. You can read each one while you wait for your coffee. In the preface he warns you honestly: the universe is under no obligation to make sense to you.

The chapters look separate, but one thread runs through them. It stretches from the first second of the universe, through the laws of physics and the stars, to the atoms of your own body. Where it leads will become clear at the end.

Idea 1. A billion and one

We were not supposed to be here.

In its first moments, the universe was a hot soup of particles and their twins. Those twins are antimatter: an antiparticle has the same mass as its particle, but the opposite charge and some other opposite properties. When a particle meets its antiparticle, both vanish in a flash of energy. Had there been equal amounts of each, they would have wiped each other out and left nothing but light.

But by the estimate Tyson gives, for every billion particles of antimatter there were a billion and one particles of matter. Everything grew out of that tiny surplus: the stars, the planets, and you.

Status: the picture of a hot beginning, known as the Big Bang, is accepted science. Why matter outweighed antimatter is still not known for sure.

A Livria analogy: a billion couples leave the dance floor in pairs, and the hall empties. One extra person is left standing, and the whole next show is about them.

A world that feels solid can rest on a difference of one part in a billion. And everyone reading this line is made of that very surplus.

Read in Livria

About the author

Neil deGrasse Tyson is an American astrophysicist, director of the Hayden Planetarium at the American Museum of Natural History in New York, a science communicator, and the host of the series Cosmos: A Spacetime Odyssey.

All books by this author: Neil deGrasse Tyson

Terms from the book

  • Wilson
  • Newton
  • Rubin
  • Dark matter
  • Dark energy
  • Helium
  • Big Bang
  • Penzias
  • Cosmic microwave background
  • Antimatter
  • Essays: Short pieces of writing that reflect on a single subject. The chapters of this book grew out of Tyson's columns in Natural History magazine.
  • Radio astronomers: Scientists who study space not through visible light but through radio waves, using large antennas called radio telescopes.
  • Zwicky: Fritz Zwicky, a Swiss astronomer who worked in the United States. In 1933 he was the first to notice that the visible matter was not enough to hold a cluster of galaxies together, and he called the missing part "dark matter".
  • Coma Berenices: A constellation of the northern sky. In its direction lies a huge cluster of more than a thousand galaxies, the one Zwicky studied.
  • Spectrum: The rainbow that light splits into when it passes through a prism. Every chemical element leaves its own lines in a spectrum, like a fingerprint.
  • Periodic table: A table of all known chemical elements, arranged by their properties. Its foundation was laid by the Russian chemist Dmitri Mendeleev in 1869.
  • Cosmic perspective: Tyson's phrase for looking at life with the scale of the universe in mind. It is the author's view of the world, not a scientific term.

All terms

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