¹ Cover ltr, James A. Van Allen to Joseph Kaplan, 28 Sept 1955, and enclosure,"A Proposal for Cosmic Ray Observations in Earth Satellites," Satellite Experiments file, folder 32.1, Archives of the National Academy of Sciences: IGY USNC (hereafter cited as NASA Archives: IGY USNC).

³ "A Proposal for Cosmic Ray Observations in Earth Satellites," encl to ltr, Van Allen to Kaplan, pp. 2-11; min 6th mtg TPESP, 7-8 June 1956, p. 11.

⁴ S. Fred Singer, "Measurement of Meteoric Dust Erosion of the Satellite Skin," 20 Oct 1955, Satellite Experiments file, folder 322, NAS Archives: IGY USNC.

^{5 "}Project Vanguard Scientific Research Program," p. 2, attachment 4 to min 2d mtg, TPESP, 21 Nov 1955; interview, Homer Newell, 19 Dec 1967.

⁶ Min 2d mtg TPESP, 21 Nov 1955, attachment 4, pp. 2-3.

⁷ Ibid., pp. 2, 4.

⁸ lbid., pp. 3-4.

⁹ James A. Van Allen, ed., Scientific Uses of Earth Satellites (Ann Arbor: Univ. of Michigan Press, May 1956).

¹⁰ Papers presented at the symposium, 26-28 Jan 1956.

¹¹ Min 1st mtg WGII, 2 Mar 1956, pp. 1-3.

¹² See n. 10 and chapter 9, pp. 155f.; min 3d mtg TPESP, 29 Jan 1956, p. 3, and attachments C, F, and G; Cosmic Ray Observations, proposed by James A. Van Allen, 20 Jan 1956, Satellite Experiments file, folder 32.1, NAS Archives: IGY USNC.

¹³ Min 1st mtg WGII, 2 Mar 1956, pp. 4-8.

¹⁴ Ibid., pp. 5-8.

¹⁵ Interview, John W. Townsend, 12 Mar 1968.

¹⁶ Satellite Experiments file, folders 32.1, 32.2, 32.4, 32.6, 32.7, and 32.8, NAS Archives: IGY USNC; min 1st mtg WGII, 2 Mar 1956, pp. 5-7, and 5th mtg 6 Feb 1957; min 6th mtg TPESP, 7 Jun 1956, p. 7.

¹⁷ Folder 32.3, Satellite Experiments file, NAS Archives: IGY USNC; min 2d mtg WGII, 4 Jun 1956, pp. 5-11; min 6th mtg TPESP, 7 Jun 1956, pp. 4, 7. For fuller description of the experiments that received financial support see Lloyd V. Berkner, ed., "Manual on Rockets and Satellites," vol. 6 of Annals of the International Geophysical Year (New York: Pergamon Press, 1958), pp. 310-343; and IGY Report 21, pp. 593-624.

¹⁸ Min 2d mtg WGII, p. 4; min 6th mtg TPESP, 7 June 1956, p. 7.

¹⁹ Min 4th mtg TPESP, p. 6; 5th mtg 20 Apr 1956, p. 3; and 6th mtg, 7 June 1956, pp. 4, 7.

²⁰ See J. G. Reid, "Status of Internal Experiments for Satellites," 23 Oct 1956, general correspondence file on Internal Instrumentation, 32; Satellite Experiment file, 32.9, NAS Archives: IGY USNC; min 4th mtg WGII, 3 Dec 1956 (p. 4), and 5th mtg, 6 Feb 1957 (p. 17); min 9th mtg TPESP, 3-4 Dec 1956, p. 13; Robert W. Stroup, "The Vanguard Satellite Experiments," Naval Research Laboratory, 4 Feb 1958, pp. 7-8.

²¹ Min 4th mtg WGII, pp. 7-8; min 9th mtg TPESP, pp. 9-10; Stroup, op. cit., pp. 8-9.

²² Ibid.; Verner E. Suami, "Radiation Balance of the Earth," Satellite Experiments file, folder 32.11, NAS Archives: IGY USNC; min 4th mtg WGII, 3 Dec 1956, p. 11, and 5th mtg, 6 Feb 1957, pp. 19-21.

²³ Min 5th mtg WGII, pp. 15-21; min 9th mtg TPESP, 3-4 Dec 1956, pp. 9-10, and 10th mtg, 7 Feb 1957, pp. 4-6.

²⁴ Satellite Experiments file folders, 32.2, 32.3, 32.10, 32.12, NAS Archives: IGY USNC; see also IGY Report, 21, pp. 565, 598, 600, 615, 621; min 11th mtg TPESP, 1 May 1957 (p. 7), and 16th mtg, 12 Feb 1958 (p. 9); Richard Porter notes on draft of this chapter. See also chapters 1, pp. 15-16, and 3, pp. 45-46.

²⁵ Min 9th mtg TPESP, 5 Dec 1956, p. 12; 10th mtg, 7 Feb 1957, pp. 8-9; 11th mtg, 1 May 1957, p. 9.

²⁶ Interviews, John Townsend and Robert W. Stroup, 12 Mar 1968.

²⁷ Interview, Robert C. Baumann, 13 Mar 1968; report on conference at NRL, 24-26 April 1957; attachment A to min 11th mtg TPESP.

²⁸ Richard Tousey, "Visibility of an Earth Satellite," Astronautica Acta, vol. 2, 1956, p. 2; interviews, Tousey, 28 Mar 1968; Whitney Matthews, 14 Mar, and Milton Schach, 27 Mar 1968; report on conference, 24-26 April 1957.

²⁹ Interviews, Townsend, 12 Mar, and Milton Schach, 27 Mar 1968.

³⁰ Report on conference, 24-26 Apr 1957; IGY Report 21, pp. 625-626; interviews, John Townsend, Robert Stroup, Whitney Matthews, Robert Baumann, 12 Mar 1968, John Hagen, 19 Mar 1968, Milton Schach, 27 Mar 1968, and Richard Tousey, 28 Mar 1968.

³¹ Report on conference, 24-26 April 1957; IGY Report 21, pp. 625-626; and min 11th mtg TPESP, p. 8, and attachment B, pp. 2-3.

³² Ltr, Hagen to Porter, 4 Sept 1956, attachment G to min 7th mtg TPESP, Sept 1956; conf rpt, 24-26 Apr 1957.

³³ Private communication to the author.

³⁴ Funding History of Project Vanguard, encl 2 to NRL 3001-18, NHF.

³⁵ Interview, Thomas E. Jenkins, 6 Mar 1967.

³⁶ Senate, Committee on Appropriations, Hearings on Supplemental Appropriation Bill for 1958, 85th Cong., 1st sess., 2 Aug 1957, p. 98.

³⁷ Ibid., 98-99, 110-117.

³⁸ Interview, Milton Rosen, 17 Nov 1966.

³⁹ See chapter 10.

⁴⁰ Interview, Odishaw, 4 Oct 1967; min 12th mtg TPESP, 3 Oct 1957, pp. 3-4.