Secrets of the Hoary Deep: A Personal History of Modern Astronomy

SIX: The First Orbiting X-Ray Observatory: Uhuru

SIX A Slow Start—Design Concept—The Moment of Truth: Launch, December 12, 1970— First Flush: Initial Uhuru Results The First Orbiting X-Ray Observatory: Uhuru 77 A Slow Start Although the concept for the first orbiting x-ray observatory was already included in the strategic blueprint submitted to NASA in 1963 (described in Chapter 5), the formal proposal,“An X-Ray Explorer to Survey Galactic and Extragalactic Sources,” was submitted to NASA on April 8, 1964.1 The proposal was approved shortly thereafter by a NASA Reviewing Committee of Astronomers. The proposed launch date was December 1965, 18 months after the start of the contract that we expected to receive in June 1964. We were jubilant and most anxious to start work. But conflicting institutional interests came into play, so that NASA delayed the program and its launch by five years. We proposed to build both the experiment and the spacecraft.Though the spacecraft we needed was not complicated or expensive,it was different from any other in the NASA program; we proposed a design almost identical to that of the Television and Infrared Observational Satellite (TIROS).The new requirement was that it should rotate slowly in a controlled manner; this feature was uniquely suited for our research, but it meant that the craft would not fit the mold of OAO, OSO, POGO, or any other series of NASA space- craft. Although I did not realize it at the time, I was entering into a philosophical conflict with NASA that was to last throughout my scientific career. The conflict had its origin at the formation of NASA,when a decision had to be made on the selection process for the scientific research to be undertaken by the agency. Should the responsibility to select the science be entrusted to the Space Science Board of the National Academy of Sciences? Or should NASA itself make the scientific decisions? John Naugle (one of the best science administrators NASA ever had) described this early struggle in the book First among Equals, a 1991 publication of NASA’s History Office. He outlined how NASA had wrestled the power of making science decisions fromtheNationalAcademyof Sciences,andhowthesystemhadsubsequently worked. When he sent me a complimentary copy of the book, I congratulated him on his scholarly approach but asked whether he still thought that NASA’s victory had ultimately been in the best interest of science. Making NASA responsible for the scientific program favored a system standardized at the top (the spacecraft level) rather than at the bottom (the component level). For ease of management, NASA preferred to plan a small number of missions, which its centers could manage. For these missions, a NASA contractor would build identical spacecraft that would be flown in a series. The scientific community was then asked to submit instrument proposals that would fit within the pre-established design characteristics of the series. While worrying about this uniformity at the top, NASA never paid attention to the standardization of electronic components common to all spacecraft , such as batteries, solar cells, power systems, transmission systems, aspect systems,and recorders.If standardization at this level had been pursued, it would have allowed the assembly of custom-designed spacecraft from offthe -shelf items, with little need for specially built subsystems. It is difficult to fathom why this standarization of electronic components was not institutionalized at NASA. But an essential element of the decision was that the diversity implied by this approach entailed decentralized control of the process of design and integration;it would have rested in the hands of the experimenters themselves,with concomitant loss of control and power by the NASA bureaucracy.No matter how attractive the concept might be for the proposed X-Ray Explorer, the AS&E scientists could not be allowed to have responsibility for the spacecraft and its integration.A NASA center willing to manage the program had to be found, but because it consisted of only a single spacecraft, no NASA center was interested. It was not until the X-Ray Explorer became the prototype for a new series of small astronomy satellites that it became acceptable. S E C R E T S O F T H E H O A R Y D E E P 78 My own opinion was that NASA was there to enable scientists to carry out their work and not to establish scientific direction (a...