The astronomer's universe is almost unbelievably immense. "One hundred billion stars in the galaxy have evolved through processes of star birth similar to that of the Sun. Far beyond the Milky Way there are perhaps another 100 billion galaxies, each containing a similar quota of stars."
The astronomer's universe is incredibly complex. Forever fleeing their own beginning at the Big Bang, each galaxy recedes from the rest into the nothingness. In each of these "island universes," this intricate star evolution is repeated countless times in endless variations. A star's mass determines which of many bizarre destinies awaits it: red giant, white dwarf, supernova, or, strangest of all, a black hole -- a star so massive that it has effectively removed itself from the universe. All around us, radio astronomy reveals a violent x-ray and gamma ray sky, ablaze with oddities such as antimatter and quasars. Further out on the frontiers of our knowledge -- more in the realm of speculation -- are gravity waves and perhaps other intelligent life forms.
The astronomer's universe is a constantly changing one. "The science of astronomy was celestial mechanics; astrophysics did not emerge until the end of the nineteenth century." In the twentieth century, astrophysics itself has been radically transformed, and has been supplemented by dramatic advances in scientific instrumentation and exploration. And the astronomer's universe has continued to change in the 11 years since this book was published, with new theories and instruments coming ever faster. Written just before the Hubble Space Telescope was launched, this statement is a heartbreaking reminder that its tragedies (and subsequent triumphs) were still in the future: "...the 2.4-meter primary mirror of the HST is the finest ever produced."
In spite of all this, the astronomer's universe is reassuring in its comprehensibility. The clockwork of the heavens is open for our inspection. And, as this book quotes the novelist Aldous Huxley, "...the more we know the more fantastic the world becomes and the profounder the surrounding darkness."
The Astronomer's Universe is Herbert Friedman's comprehensive and clearly-conveyed summary of modern cosmology. Prior to his death last year, Friedman's long and distinguished career made him one of our nation's most-honored scientists. In an especially interesting chapter of this book, Friedman relates his personal role in putting the first scientific instruments into space, aboard V-2 rockets captured from the Germans after World War II. This was when astronomy entered the space age, and Friedman was there. As with any book, a few mistakes creep in. There is a reference to that old misconception, "Galileo's invention of the telescope," and in the glossary we learn that a light-year is equal to 186,000 miles -- that's actually a light-second. But overwhelmingly, this an authoritative and important overview; the universe in one book, if you will. The astronomer's universe would be an emptier one if Dr. Friedman had not been here to study and explain it.