76 ANNUAL REPORT SMITHSONIAN INSTITUTION, 195 7 



Whipple, Fred L., Davis, R. J., and Zikker, J. B. The orbit of a small earth 

 satellite. In "Scientific Uses of Earth Satellites," pp. 1-22. University of 

 Michigan Press, 1956. 



. Time available for the optical observation of an earth satellite. 



Ibid., pp. 23-28. 



Whipple, Feed L., and Jacchia, L. G. The Harvard photographic meteor pro- 

 gramme. In "Vistas in Astronomy," vol. 2. Pergamon Press, 1956. 



. The orbits of 308 meteors photographed with Super-Schmidt 



cameras [abstract]. Astron. Journ., vol. 62, pp. 37-38, 1957. 



. Reduction methods for photographic meteor trails. Smithsonian 



Contr. Astrophys., vol. 1, pp. 183-206, 1957. 

 Whipple, Feed L., and Wright, F. W. Methods for the study of shower radiants 

 from photographic meteor trails. Smithsonian Contr. Astrophys., vol. 1, 

 pp. 239-243, 1957. 



OTHER ACTIVITIES 



A conference on Constants for Orbital Calculations was held at 

 the Astrophysical Observatory on January 25, 1957. On February 

 15, 1957, a conference on Solar Measurements was held at the Smith- 

 sonian Institution, Washington, D. C. The Smithsonian Astrophysi- 

 cal Observatory and the Harvard College Observatory acted as co- 

 hosts at the meetings of the American Astronomical Society, May 8-11, 

 1957. The Astrophysical Observatory was host to the international 

 Third Cosmical Gas Dynamics Symposium, June 24-29, 1957. 



Various staff members attended meetings of the American Astro- 

 nomical Society, the American Physical Society, and the Third Cos- 

 mical Gas Dynamics Symposium. 



Dr. E. L. Fireman attended the National Academy of Sciences con- 

 ference on Nuclear Geology and the Gordon Conference on Nuclear 

 Chemistry. 



Dr. John S. Rinehart participated in the Third International 

 Symposium on High Speed Photography in London, September 1956 ; 

 the Institution of Mechanical Engineers Conference on the Properties 

 of Materials at High Rates of Strain in London, May 1957 ; the Air 

 Force Office of Scientific Research and Naval Research Laboratory 

 Symposium on Hyper- velocity and Impact Effects, May 1957; and 

 the National Academy of Sciences Symposium on Tektites, Wash- 

 ington, June 1957. 



In the interest of obtaining optical tracking sites for the Satellite 

 Tracking Program, Dr. J. Allen Hynek traveled to South America, 

 Visiting Montevideo, Uruguay; Santiago, Chile; Lima, Peru; 

 Antofagasta, Peru; Arequipa, Peru; and Curasao, N. W. I., during 

 January 1957. He also traveled to Teheran, Iran; Delhi, India; 

 Tokyo, Japan ; and Hawaii during the latter part of May and early 

 June of 1957 to inspect optical tracking sites. Dr. Karl G. Henize 

 traveled to Spain and South Africa between March 20 and April 7, 

 1957, to inspect optical tracking sites. 



