My description of William Pickering is from my own observations (page 22)

Information about Vanguard came mainly from my interview with Mil­ton Rosen and was bolstered by articles and papers he gave me, including one by John Pierce describing how satellites might be used for telecom­munications, one that Rosen sent on 3 March 1955 describing the utility of the Viking rocket for a satellite launch vehicle, and a memo on the same date from John Mengel and Roger Eastman outlining Minitrack.

A considerable amount of useful information about Vanguard can also be found in Green’s and Lomask’s book and in the NASA History Office (see notes for the prologue). Green and Lomask give details of the costs and of the rival merits of the Projects Orbiter and Vanguard pro­posals, including details of the miniaturization to be found in Vanguard (page 26).

Milton Rosen told me that von Braun asked for a chance to make a sec­ond presentation of Project Orbiter to the Stewart committee, and of the anxiety with which he (Rosen) watched the presentation and the disbe­lief and elation felt by the NRL team when they learned that the com­mittee had backed Project Vanguard (page 26).

My interview with William Pickering and his oral history, given to Mary Terral for the archives of the California Institute of Technology, provide details of Project Orbiter and how it evolved from von Braun’s original proposal.

Information about the long playing rocket (the euphemism by which a rocket capable of reaching orbit was known), its costs, and the costs of the satellite program, as well as their acceptance by the USNC—IGY is found in the following minutes, located at the National Academy of Sciences: third meeting of the USNC executive committee (January 7, 1955), dur­ing which the technical panel on rocketry was asked to report on the technical feasibility of satellites; first meeting of the technical panel on rocketry (January 22, 1955) during which a subcommittee comprising William Pickering, Milton Rosen, and John Townsend was formed; first meeting of the subcommittee evaluating the feasibility of a satellite launch (February 3 and 4, 1955, in Pasadena). No minutes, though William Pick­ering remembers the first meeting. Fourth meeting of the executive com­mittee of the USNC, during which members were told that the technical evaluation of a satellite was ongoing; On March 5, 1955, there was a meeting between Joseph Kaplan and Hugh Odishaw, the administrative secretary of the USNC, to discuss security procedures surrounding the work of the subcommittee of the technical panel on rocketry. They con­cluded that the report would be classified but that the committee would prepare an unclassified report for the executive committee; On March 9, 1955, the technical panel on rocketry accepted a classified report on the feasibility of launching a satellite and prepared an unclassified version for the USNC’s executive committee; On March 8 — 10, the fifth meeting of the USNC executive committee discussed the rocketry panel’s report and debated whether to back the inclusion of satellites in the IGY. Unusually, the notes from this meeting are handwritten and hard to decipher. The most vocal discussants were Merle Tuve and Athelstan Spilhaus. Tuve expressed doubt about the inclusion of a satellite in the IGY; Spilhaus was strongly in favor. What caused Tuve concern was the classified nature of the project. In the end, the meeting agreed that if the long playing rocket were still classified by January 1956, then it should be dropped from the program. The seventh meeting of the USNC took place on May 5, 1955. An agenda item on the LPR refers to an attachment that is not included in the archives. This meeting was in the period following Quarles’ approach to the IGY and prior to Eisenhower’s public announcement that there would be a satellite program. Hugh Odishaw was writing and phoning the NSF at this stage, pushing for a decision on the satellite bud­get and seemingly unaware of the higher policy decisions in which the satellite program was caught.

Odishaw’s letters and Joseph Kaplans correspondence with Alan Water­man, the director of the National Science Foundation, and Detlev Bronk, the president of the National Academy of Sciences, are in the correspon­dence files of the IGY archives at the NAS.

Details of the curtailment of the satellite program (page 30) in the year following President Eisenhower’s announcement that it would go ahead are also to be found in the archives of the NAS. The USNC discussed the Earth satellite program at its tenth meeting on 13 July 1956. The minutes, classified as administratively confidential, say, “For reasons of economy, the Earth satellite program has been curtailed from 12 attempted launching to six.” Hugh Odishaw drew the committee’s attention to the need for con­fidentiality, “lest knowledge of the curtailment of the program should lead to an international loss of prestige by the U. S.”

The interaction between the IGY and national security policy comes pri­marily from R. Cargill Hall, “The Eisenhower Administration and the Cold War, Framing American Astronautics to Serve National Security,” in Prologue, Quarterly of the National Archives, spring 1996. It seems likely that the criteria that the Stewart Committee were given in order to decide between Projects Orbiter and Vanguard were chosen to ensure that the IGY could indeed be a “stalking horse” for the launch of a reconnaissance satellite.

Information about the Stewart Committee (page 25) can be found in the oral history by Homer Joe Stewart in the archives of the California Insti­tute of Technology and in Vanguard—A History (NASA History Series SP4202), by Constance Green and Milton Lomask. Milton Rosen also gave me information about the way the Stewart Committee voted and the reasoning behind their decision.

Homer Joe Stewart was interviewed by John L. Greenberg on October 13 and 19 and November 2 and 9, 1982, for an oral history, which is in the archives of the California Institute of Technology.

Details of how the scientists learned of the launch of Sputnik come from conversations with Walter Sullivan, William Pickering, and John Townsend (page 30).

Books consulted for chapter 2, as well as for the prologue and chapter 11 are Beyond the Atmosphere, Early Years of Space Science, by Homer E. Newell (SP4211—NASA History Series); Science with a Vengeance, How the Military Created the US Space Sciences after World War If by David DeVorkin (Springer-Verlag, 1992); The Viking Rocket Story; by Milton W. Rosen (Faber, 1955).