American Scientist

Giant Telescopes: Astronomical Ambition and the Promise of Technology. W. Patrick McCray. viii + 367 pp. Harvard University Press, 2004. $45.

As an arriving student at Harvard more than 30 years ago, I sought out some famous astronomers at a reception to welcome newcomers. As I approached them, planning to introduce myself, I couldn't help overhearing the end of a conversation that shocked me: A visiting astronomer was telling the observatory director heatedly, "Your observatory is getting too damn big!" He glanced at me with disdain and walked away. Welcome, indeed, to the big leagues of astronomy.

The visitor that day was Jesse Greenstein of Caltech, a powerful champion of small, elite academic programs designed to serve only a few astronomers, giving them private access to the biggest telescopes. And the recipient of his ire was Leo Goldberg, whose Harvard College Observatory took a team approach to astronomy and space science; Goldberg often supported drives to build national telescopes for use by all astronomers.

Greenstein's jab at Goldberg that day typifies a cultural battle that still rages. The controversy is especially heated among optical astronomers, who are more contentious than any other group of scientists I know. They regularly bicker over whether astronomy should be practiced by small groups using private telescopes or by large teams at open-
access national facilities. It's a classic confrontation of "haves" and "have-nots," but a complex one, because when it comes to owning powerful telescopes, rich East Coast institutions like Harvard are among the have-nots.

In Giant Telescopes, science historian W. Patrick McCray addresses this cultural divide, especially the professional rivalry between private and national observatories. In the first few chapters, he uses the careers of Greenstein and Goldberg to illustrate it, describing the many clashes that took place between the two men in the 1960s and 1970s as it became increasingly hard for solitary astronomers to practice traditional modes of investigation as individuals. The general reader is likely to find McCray's account of the "astropolitics" of this era amusing, although the narrative suffers somewhat from a lack of intimate detail because he didn't know these colorful characters personally.

The middle chapters of the book highlight a debate that occurred in the 1980s about the design of big telescopes (ones larger than the archetypal 5-meter Palomar device in California). Should the new mirrors be single, monolithic pieces of polished glass? Or should they be clusters of smaller, less expensive mirrors working together? McCray relates well the sad story of the inability of the National Optical Astronomy Observatory to bring together the astronomy community as the consortium struggled for survival. It scaled back its plans first for the 25-meter Next Generation Telescope and then for the 15-meter National New Technology Telescope, finally settling on twin 8-meter Gemini telescopes, one in each hemisphere. This part of the book will be slow going for the general reader—there are few diagrams or illustrations to help the uninitiated, and McCray's close probing of the record does not make for a very exciting read.

The final chapters chronicle the ordeal of building the Gemini national telescopes in the 1990s, each smaller than the private Keck telescopes in Hawaii and a good deal less powerful than Europe's Very Large Telescope in Chile. The Gemini observatories, although originally conceived as an American undertaking, became an international endeavor, and the telescopes are now available to any astronomer from any of the countries that collaborated on their construction (the United States, the United Kingdom, Canada, Chile, Australia, Argentina and Brazil). In his account of the policy, politics and engineering leading up to the actual building of the observatories, and throughout the book, McCray relies on archived correspondence, technical documents and interviews with some of the principals involved. This saga will likely interest most those who lived though the troubled project; I was mostly on the sidelines and thus had a tough time staying with this section of the text.

The most insightful and readable part of the book is the short concluding chapter. Here, McCray weighs the question of whether the astronomy community today is becoming more like the high-energy physics community, with its big budgets, huge teams and pipeline data collection. He also wonders whether European optical astronomers, who are more unified than their fragmented American counterparts, are about to achieve the same sort of dominance as European high-energy physicists.

My impression is that in books of this type, historians often write, without knowing it, a kind of revisionist history. McCray was not a player in, or even a witness to, any of the decisive events he describes. That may make it easier for him to be objective as he assesses the record, but it also means that he lacks an insider's view, however subjective. Specifically, the interviews he conducted years after the key events unfolded have in some cases yielded little more than self-serving statements. Accordingly, the book does not capture particularly well the daily pressures, regular infighting,peculiar culture, methods and triumphs of today's optical astronomers doing big science in a golden age of astrophysics.—Eric J. Chaisson, Astrophysics, Tufts University