Welcome to the Universe: An Astrophysical Tour
by Neil deGrasse Tyson, Michael A. Strauss & J. Richard Gott
Thanks to Cosmos: A Spacetime Odyssey, the 2014 television show inspired by the 1980 Carl Sagan classic, Neil deGrasse Tyson is probably the best-known of the trio of leading astrophysicists presenting this book. But all three share a passion for their subject as well as a long history of helping non-scientific audiences understand the wonders of the universe.
Apart from his television career, Tyson is director of the Hayden Planetarium at the American Museum of Natural History in New York, while Strauss and Gott are professors of astrophysics at Princeton University. Billed as a “personal guided tour of the cosmos”, this book is both a wonderful starter pack on astrophysics for newcomers, as well as a charming excursion for the more knowledgeable.
In fact, it is something of a reprise for Tyson, Strauss and Gott, who once co-taught the introductory astronomy course for non-science majors at Princeton (and what a treat that must have been). That series attracted so many students it had to be moved to the biggest lecture hall on campus.
The division of labour in that course saw Tyson teaching “Stars and Planets”, Strauss covering “Galaxies and Quasars” and Gott (the author of the wonderfully baffling Time Travel in Einstein’s Universe) taking on the challenging “Einstein, Relativity and Cosmology” segment. And the book keeps those specialities in place as it moves through three parts, each with its individual author lending his own style to proceedings. (They’re all good, but Tyson, with his more practised hand at public outreach, might just have the populist edge.)
The tour they take us on is a comprehensive one, not just unlocking the mysteries of the universe but celebrating the human journey through the years as mankind has grappled with the concepts involved in the cosmos, from Newton to Einstein and Stephen Hawking.
Gott, in particular, is eager for us to see not just the majesty of creation, but the stunning human achievement that has led us to understand as much about the cosmos as we do today.
We should be proud to be members of the human race that in such a short time has learned how gravity works, how stars evolve and just how old the universe is. As he writes: “We are not very powerful, and we have not been around for very long. But we are intelligent creatures and we have learned a lot about the universe and the laws that govern it… It is a stunning accomplishment.”
They marvel that we have measured the quantity and density of dark matter in the universe without ever having even seen it
Tyson, Gott and Strauss are each careful at painting a picture of the head-swimming concepts involved, whether that is the basic matter of trying to get our heads around the sheer scale of the universe (“This leaves many people thrilled, but feeling tiny and insignificant at the same time”) to finding a contextual point to imagine the density of the neutron star (100 million elephants in a thimble, they say).
Since the three scientists taught the Princeton course, our knowledge of the universe has exploded. Tyson’s once-controversial views of the nature of Pluto have been justified, thousands of new planets have been discovered in distant solar systems with the intriguing possibilities that some may harbour life and the Higgs boson and gravitational waves have moved from theory to fact, with the exciting detection by the Laser Interferometer Gravitational-wave Observatory.
The tour takes in all this along with close encounters with quasars and black holes, an explanation of the Big Bang and an introduction to the leading edge of modern theoretical physics – multiverses, superstrings and M-theory. Our guides also introduce the more speculative, in wormholes and time travel, and explain how scientists have, thanks to observations by the Hubble Space Telescope and the Sloan Digital Sky Survey among other tools, developed the standard cosmological model to unprecedented accuracy. They marvel that we have measured the quantity and density of dark matter in the universe without ever having even seen it!
While you don’t need to know any science to take the tour, there is plenty here for those who do, with the entertaining narrative bringing new insights to the landscape of the universe and how it formed.
Nor does it talk down to the reader or shy away from some of the trickier and more sophisticated concepts about how the universe works. That said, the mathematics, when it is required, is well and clearly explained and adds to the enjoyment of this weighty volume.
Asked the one thing he wishes more people understood about the universe, Tyson nominates “the incomprehensible depths of time and the mind-stretching depths of space”, which “conspire to leave the human mind all but incapable of grasping the entire universe in one thought”.
Welcome to the Universe is more than a breathtaking guide to the cosmos. It is a unique bridge between popular science and textbooks, admirably achieving Tyson’s goal to “empower you to understand the operations of nature”.