The Universe in a Mirror: The Saga of the Hubble Space Telescope and the Visionaries Who Built It (New in Paper) [Paperback]

Quick: name a satellite. If you can think of one name, it is probably the Hubble, officially the Hubble Space Telescope, and the reason you might know of it by name when all those other communications and positioning satellites are up there (and also the International Space Station) is that images from Hubble are part of popular culture as well as scientific culture. Hubble has been an amazing success, but often just barely. It took a long time in coming, and might at any point in the planning stage have been shifted aside for other space goals. The complicated story of how Hubble got planned and launched and repaired is told with enthusiasm and detail in _The Universe in a Mirror: The Saga of the Hubble Space Telescope and the Visionaries Who Built It_ (Princeton University Press). Hubble is not just beloved by the public, it has been an extraordinary research tool, and deserves this fine biography, which tells a great deal not only about the gadget but about the boffins who made it all happen.

There are good reasons to have a telescope in space, mainly the avoidance of the distortion and filtering of the Earth's atmosphere. An orbiting telescope got a realistic proposal in 1946 with a paper for RAND by Lyman Spitzer, an astronomer who was ending up some sonar research after the war. Spitzer remembered thirty years later, "Most astronomers didn't take it seriously. They thought I was sort of ... wild-eyed or wide-eyed, one or the other." Zimmerman details the scientific and engineering planning and also the lobbying and horse-trading that had to go on to get the Hubble built and launched. It is a confusing tale, reflecting the peculiar mindset of the bureaucracy. Hubble might have been bigger (a bigger telescope lets more light in so it can see more), might have been put up faster, and might have been more broadly useful if politics and budget games had not gotten in the way. A case could be made, too, that such difficulties forced the mirror-building firm to skip quality control steps that would have noticed that the mirror, which should have been corrected to within ten billionths of an inch, was not ground into the correct shape. The Hubble once in orbit could only send back blurred pictures; it could have been, Zimmerman says, "the greatest catastrophe to hit American astronomy ever," and it is agonizing to read about the astronomers who slowly realized that the telescope they had so long championed was going to be useless. It proved to be a big embarrassment, of course, but after a while, an engineer, inspired by the design of the showerhead in his hotel room, found a solution which was deployed on a flight of the Space Shuttle in 1993.

Since then, the telescope has been sending back lots of information. Hubble data has been the foundation of 35% of all the scientific output from NASA, including information on extra-solar planets and a confirmation of the time of the Big Bang to 13.7 billion years ago. And then there are the pictures, some of them magnificent pictures. There are popular classics, like the towering pillars within the Eagle Nebula, or the astonishing "Ultra Deep Field" pictures that look like a patch of sky with an extreme number of stars in it, only further resolution shows that each star is not a star, but a galaxy full of its own stars. The pictures can be found in elementary classrooms, as wallpaper on personal computers, and in music videos. They account for the public interest in Hubble and in further construction of space and land telescopes. There was also public revulsion when NASA planned no longer to service Hubble so that it would lose power and die. Hubble won't last forever, but it has been given a reprieve, and so more pictures are coming (there are 25 color plates in this book). One important lesson that Zimmerman shows we have learned is that a robot camera is a splendid tool as an observatory, but that humans must be available, too; only the teamwork of robot and humans could have brought about this success story. There is also more than a hint that the procurement and planning systems described here are far from perfect, and have not only caused financial and efficiency costs but also have ruined careers and personal lives of some of the scientists who are part of this story. It is a dismal lesson, but Hubble has been a glorious success, and Zimmerman's book is a useful history and a reminder of how much popular support there is for scientific efforts.

The Universe in a Mirror: The Saga of the Hubble Space Telescope and the Visionaries Who Built It
This book describes the Hubble Telescope Program and its predecessors in a most thorough and beautifully written exposition of NASA's efforts and problems in constructing the telescope. Unfortunately, in accordance with NASA's policies, it only contains the activities and decisions made by NASA management.

As I was Chief Engineer at Itek Optical Systems for the competing Large Space Telescope Program, the Hubble's predecessor, many technical problems were created by NASA's program management and convoluted approach to budget management, as explained by Mr. Zimmermann. The Large Space Telescope was a 3 meter aperture telescope very similar to the Hubble excepting for its much larger size. There were no 3 meter test facilities available in the country for full aperture high vacuum testing of the primary mirror. The projected cost of the 3 meter aperture LST far exceeded the amount that NASA thought was available. The NASA management opted for a null lens testing arrangement for the primary mirror construction which, as explained in Zimmermann's book, led to grinding and polishing the primary mirror to an incorrect prescription.

Furthermore, the aperture of the Hubble Telescope was reduced to 2 meters to take advantage of a classified test facility. A colleage of mine who had formerly worked for Perkin Elmer, the maker of the Hubble, told me of the testing failures that had occurred there, and his subsequent role explaining the problem to Congress in an investigation of the program. Perkin Elmer had a back up knife edge testing program, also run by an engineer that had once worked for me. The knife edge testing showed that the Hubble mirror had been polished incorrectly. Another Company had access to the 2 meter classified test facility, and was awarded contracts to polish "back up" mirrors--these were tested at full aperture and were made perfectly to the correct prescription. Therefore, Perkin Elmer and NASA management had prior knowledge of the error in figure of the Hubble but refused to believe the test results. Since the correct mirrors had been made by a competitor, it apparently was politically untenable for NASA to install the "backup" mirror set.

If I were to criticise, Mr. Zimmermann's book, it would be to say that by following the NASA information line solely, he missed an important set of events that affected the telescope program. Nevertheless, his exposition of the troubled program was accurate, and detailed, and politically correct.
Roger Lee

This book is excellent on the politics, including pictures of the players. And it has a decent section of Hubble color images. But it is curiously lacking on information about the completed instrument. Just a few more pages would have been extremely informative as a complement to the political wrangling. There is no photograph of the completed telescope, either on the ground or as deployed in space. Worse, there are no diagrams that show how it works. And after much discussion of the Vidicon versus CCD battles, we get no confirmation as to the final size of the CCD (was it 2000 x 2000 pixels in an array of four sensors?) and how the light gets from the mirror to the CCD. In an era where digital cameras embodying CCD technolgy are widespread, where many readers are conversant in talking about pixel dimensions of their home images, where many personal cameras have more than 2000 x 2000 pixels, this seems a strange omission. Apologists will say the information can be found elsewhere, but all it would have taken is a handful more pages (10?) to include it here and make the book less skewed to the politics. Even if Zimmerman, as a journalist, didn't see the need for this, I wonder why an editor didn't insist on it?