74 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1957 



for these instruments to photograph a highly reflecting sphere the 

 size of a tennis ball at a distance of more than 200 miles. 



The popular interest and cooperation generated by the Moon- 

 watch program have far exceeded the expectations of the Astro- 

 physical Observatory. In the United States alone there are 90 reg- 

 istered Moonwatch teams comprising more than 1,500 voluntary 

 observers, many of whom are amateur astronomers of considerable 

 experience in the observation of the sky. A regular series of Moon- 

 watch bulletins has been initiated by the Smithsonian Astrophysi- 

 cal Observatory, published in Sky and Telescope, with reprints fur- 

 nished to all registered observers. The bulletins are regularly 

 translated into Spanish for distribution in South America and Spain, 

 while the English edition is mailed to many parts of the world. 

 Moonwatch stations have been established also in Japan, Iran, Korea, 

 Argentina, Peru, Chile, Australia, Union of South Africa, Pakistan, 

 and India. One aspect of the Moonwatch program which should not 

 be underestimated is its contribution to the creation of interest among 

 the public in scientific matters. Moonwatch teams provide oppor- 

 tunity for serious people without specific scientific training to partici- 

 pate in the IGY program and to render a definite scientific service. 



The computation and analysis division of the program is now pre- 

 pared, through the use of electronic calculators, to handle orbital com- 

 putations from the raw data furnished by the precision stations 

 as well as the Moonwatch stations. International Business Ma- 

 chines Corp. has made possible the use of their 704-computer instal- 

 lation at Massachusetts Institute of Technology. The Observatory 

 will receive up to 1 hour a day of machine time until June 30, 1959, 

 for satellite computations. IBM will also supply one or two program- 

 ers for technical assistance. 



Such computations will furnish the immediate ephemerides for 

 satellite positions, so that the precision tracking stations can be 

 properly alerted, and the Moonwatch teams and public in general 

 informed of the satellite's immediate whereabouts. The long-range 

 purposes of the computation and analysis division, however — and its 

 most important aspect — are the detailed analyses of the changes in the 

 various elements of the satellite orbit. These orbital calculations are 

 essential to the proper use of the satellite as a scientific vehicle for 

 geodetic and geophysical purposes. 



In support of upper- atmospheric studies by satellite methods Dr. 

 Sterne has completed a theoretical research on the gravitational motion 

 of a particle of small mass near a planet flattened by rotation. He dis- 

 covered a novel Hamiltonian function that led to an exact analytical 

 solution for the motion of a particle in very nearly the correct field of 

 force. Dr. Sterne also developed special mathematical procedures for 



