Planet Quest: The Epic Discovery of Alien Solar Systems
by Ken Croswell
The Free Press, 1997
hardcover, 324pp., illus.
ISBN 0-684-83252-6
US$25/C$34

The Quest for Alien Planets: Exploring Worlds Outside the Solar System
by Paul Halpern
Plenum, 1997
hardcover, 294pp., illus.
ISBN 0-306-45623-0
US$27.95

Over the last two years the discovery of extrasolar planets -- planets orbiting other stars -- has captured the imagination of scientists and ordinary people alike. Combined with tantalizing hits of past or present life on Mars and Europa, it has raised the hope that the development of life, and perhaps intelligent life, may be commonplace in the universe. Two books that provide an account of recent planetary discoveries and how they have shaped our views of the universe and the chance of life in it are Planet Quest by Ken Croswell and The Quest for Alien Planets by Paul Halpern.
     Ken Croswell's Planet Quest takes the reader on a tour of the history of planet discoveries, from the discovery of the outer planets in our own solar system through the alleged discoveries of planets around Barnard's Star and other stars, which were later refuted, to the confirmed discoveries of pulsar planets and the wealth of new extrasolar planets found in the last two years.
     Croswell explains the science and the observational techniques at a level easily understood by the layman. Moreover, his interviews with dozens of scientists involved in the search adds an extra, human dimension to the subject, as we find out about the ups and downs, the cooperation and the conflicts, researchers in the field have encountered. The book includes a detailed glossary of terms and names used in the book, along with a bibliography that includes general works and scientific papers, that make the book a good reference work in addition to its strengths as a tale of discovery.
     The Quest for Alien Planets by Paul Halpern takes a somewhat different tack to the subject. His focus is as much on the "alien" aspect of the title as planets, as he starts with a history of our studies of Mars, a planet that had been "discovered" by the ancients but long thought to harbor alien, possibly intelligent, life. From there he takes us through the discovery of planets within our own solar system and the new extrasolar worlds. He then returns to the search of alien life in the cosmos, after an odd detour into the subject of missing and dark matter.
     Planet Quest is a good book for anyone looking for the scientific and human tale of planet discovery. Halpern's The Quest for Alien Planets has a slightly different focus: it does not tell the story of the discovery of new planets as well as Croswell's book, but goes into far more detail on how these worlds, or others like them, might harbor intelligent life. For those looking to learn more about the search for extrasolar planets, though, it will be hard to beat Planet Quest.

Destination Mars: In Art, Myth, and Science
by Martin Caidin and Jay Barbree, with Susan Wright
Penguin, 1997
hardcover, 228 pp., illus.
ISBN 0-670-86020-4
US$29.95

Mars: The Living Planet
by Barry E. Digregorio with Dr. Gilbert V. Levin and Dr. Patricia Ann Straat
Frog. Ltd, 1997
hardcover, 365pp., illus.
ISBN 1-883319-58-7
US$25

It's been months after the successful landing of Mars Pathfinder and more than a year since scientists announced evidence of possible past life on Mars, yet Mars still remains of interest to people around the world. Two books examine Mars: one studies the impact Mars has had on human culture throughout history, while the other presents a highly alternative account of why life on Mars has not yet been discovered.
     Destination Mars by Jay Barbree and the late Martin Caidin takes a multidisciplinary approach to the Red Planet. Not just an account of our scientific studies of Mars, it looks it how it has shaped, and has been shaped, but human arts, literature, and culture. While giving some accounts of ancient history and the Renaissance, the book focuses on the 19th and 20th centuries, when telescopes, and later, spacecraft, were able to provide more detail on the planet, stimulating our intellect and our imaginations.
     Caidin and Barbree provide roughly equal time to both the scientific study of Mars and its changing role in popular culture. The book covers both the science of Mars missions and the Mars-related science fiction, and includes mention of ALH 84001 and the current Mars missions (still discussed in future tense in the book, as it went to press before the Pathfinder landing.) The pictures in the book, ranging from Viking images of Mars to illustrations from late 19th-century Mars science fiction, are also quite enlightening.
     Mars: The Living Planet makes a bold, but poorly-supported claim: that life has been discovered on Mars, by the Viking spacecraft, but its existence has been covered up, or simply not accepted, by NASA. He claims that the "Labeled Release" (LR) experiment on Viking, designed by Gilbert Levin and Patricia Straat (who contribute to the final chapters of the book) did detect evidence of microbial life on Mars, even though other experiments on the spacecraft turn up no such evidence. He also pushes other evidence, such as claims of "green" spots on images of Martian rocks, which seem to appear to be gray to just about everyone else.
     But why would NASA cover up a discovery as monumental as present life on Mars, when it could be so beneficial to the space program (witness the upsurge in interest in space after ALH 84001 last summer)? Digregorio claims NASA wanted a dead planet since the Viking times to pave the way for a sample return mission without fear of contamination -- even though no sample return mission was being seriously considered in the mid-1970s and even today is still years away. Digregorio's other hypotheses, which bring in everyone from Congress to the Pope (!), are even harder to swallow.
     Mars: the Living Planet is a disappointing study of life on Mars which, while far from being a closed case, almost certainly does not resemble the string of conspiracy theories Digregorio spins in his book. Destination Mars, on the other hard, is a far more enlightening, and enjoyable, account of the powerful role the Red Planet has played in our science and culture.

A Lunar-Based Analytical Laboratory
by Charles W. Gehrke, Mitchell K. Hobish, Robert W. Zumwalt, Michel Prost and Jean Desgres (eds.)
A. Deepak Publishing, 1997
hardcover, 331pp., illus.
ISBN 0-937194-41-7
US$60

A Lunar-Based Analytical Laboratory is a collection of papers presented at a 1993 conference on France on the scientific and engineering challenges of establishing a base on the Moon. Although the title suggests a discussion of scientific issues only, the papers in the book, contributed by experts from the United States, Europe, Russia, and elsewhere, cover many aspects of a lunar base, from transportation and habitation issues to the use of a base for mining, life science, astronomy and more. The one drawback to this book is that it is based on papers presented more than four years ago, and thus is not as up to date than one might like it to be. Otherwise, A Lunar-Based Analytical Laboratory is a concise, scientific look at the issues of establishing a human presence on the Moon.

After Contact: The Human Response to Extraterrestrial Life
by Albert A. Harrison
Plenum, 1997
hardcover, 363 pp.
ISBN 0-306-45621-4
US$28.95

Making Contact: A Serious Handbook for Locating and Communicating with Extraterrestrials
by Bill Fawcett (ed.)
Wm. Morrow, 1997
hardcover, 370 pp., illus.
ISBN 0-688-14486-1
US$23/C$30.50

Although there exists no concrete evidence for the existence of extraterrestrial intelligence, either through radio communication or direct visits, many people claim to have seen aliens (or abducted by aliens, etc.), driving continued interest in the subject. Two books take on the subject of contact with extraterrestials, one seriously and one far less so.
     Despite the subtitles, After Contact is the far more serious of the two books. Written by a University of California psychology professor with a long interest in SETI, the book picks up where many other studies of SETI leave off: what happens after contact is made with an extraterrestrial intelligence. What impact would knowing that other intelligences (most likely superior ones) existed in the cosmos? Harrison dismisses accounts of UFOs and focuses instead on how human culture might be irrevocably altered by contacting and sharing information with another species, drawing analogies with the culture shock that has come when vastly different human cultures have met for the first time.
     Making Contact, on the other hand, is a collection of articles by a number of UFO experts and science fiction writers on the techniques one should follow should an alien show up in your backyard. The experts write in all earnestness about talking with aliens ("If you blow it, the repercussions could be unimaginably terrible, perhaps an interstellar war that could annihilate humanity," one writer warns) and dealing with those pesky local, state, and federal authorities, among other subjects Accounts of UFO sightings are interspersed among some more credible articles, such as discussion of what shapes life might take on distant worlds (written by science fiction author David Brin).
     After Contact is a good book that serves as a logical counterpart to other books written on the search for extraterrestrial intelligence. It takes a serious look at what might happen to human culture should we do find another intelligence. Making Contact, though, serves a combination of rehashed UFO accounts and half-serious, half-silly discussions of what to do should an alien show up on your doorstep. While the truth might be out there, it's most likely not in there.