PLANET QUEST: The Epic Discovery of Alien Solar Systems

Chronicles the momentous ten month period of discovery between 1995 and 1996 that revealed no less than five new solar systems, with profound implications for the search for extraterrestrial intelligence

Astronomers have discovered the first planets circling sunlike stars, proving that our solar system is not unique...Ken Croswell takes a charming, historical approach, beginning with Giordano Bruno's vision of a multitude of worlds and continuing through the personalities and techniques involved in the latest findings.

A lively, timely history of the search for extrasolar planets- -today's hottest astronomical game. Croswell, an astronomer and journalist (The Alchemy of the Heavens, 1995), relates how, beginning with William Herschel's 1781 discovery of Uranus, the search for new planets became a holy grail for astronomers; Neptune, Pluto, and the asteroids followed in due course. (``Planet X,'' believed by some astronomers to account for perturbations in the orbit of Uranus, remains undiscovered.) But planets beyond our own system seemed too remote for even the best telescopes to spot--the nearest star system being 25 trillion miles away, and others millions of times farther than that. At that distance, only indirect methods can apply, in particular, measuring minute fluctuations in the motions of stars, which a sufficiently large planet would cause. Such fluctuations have been reported, and ascribed to distant planets, since the 1940s. But until very recently, better observations have usually deflated the discoverers' claims. (One prominent astronomer's claim of periodic motions of Barnard's Star was finally explained by a periodic wobble in his telescope.) The space age made newer techniques available. A large planet would be expected to emit large amounts of infrared light, and when the bright star Vega was found to be unexpectedly energetic in the infrared, it was taken by some as evidence of planets. (A ring of dust is the more likely answer.) These and other false alarms were the entire story until 1995, when two Swiss astronomers reported a large object in orbit around 51 Pegasi, now considered the first observation of an extrasolar planet. Croswell provides engaging portraits of the astronomers (from Giordano Bruno through Geoffrey Marcy, one of those who discovered 51 Pegasi's planet) as well as a clear, lively summary of the scientific material. A thoroughly readable addition to the astronomy bookshelf. (illustrations) -- Copyright ©1997, Kirkus Associates, LP. All rights reserved.

Croswell, following his story of the Milky Way (The Alchemy of the Heavens, 1995), addresses a most popular topic in astronomy, the planets beyond Pluto. Although Croswell was beaten in the publishing race by Donald Goldsmith (Worlds Unnumbered ), his book is distinctive from Goldsmith's in two respects: a fourth of its text concerns our solar system, and it offers somewhat more technical detail about the hunt for extrasolar globes, showering the reader with tables, graphs, and diagrams. The graphics depict the behavior of neighboring stars from which astrometers (astronomers who specialize in distance measurements) would infer the presence of planets; indeed, proving a detection is so difficult that there were several false claims before the first confirmed extrasolar planet was announced in 1993. The next frontier, finding an earthlike planet, induces Croswell to muse on the requirements of interstellar travel, a futuristic prospect that concludes this informative explanation of why contemporary astronomy is so exciting. Gilbert Taylor

After summarizing the history of the discovery of the outer planets in our solar system, science writer Croswell (The Alchemy of the Heavens, LJ 4/15/95) moves on to the exciting?and apparently authentic?recent discoveries of planets revolving around stars other than our Sun. He tells of a variety of premature "discoveries" that could not be confirmed and of more soundly based findings in the 1990s. He explains well the scientific basis of the search for remote planets and is candid about the rivalries and disagreements among the ambitious researchers in this field. Despite a speculative last chapter on the prospects for interstellar travel, Croswell wisely concentrates in general on the science (not the science fiction) of planetary searching. Highly recommended for both public and academic libraries.?Jack W. Weigel, Univ. of Michigan Lib., Ann Arbor
Copyright 1997 Reed Business Information, Inc.