SECRETARY’S REPORT 101 
rocket of the Vanguard sphere, 1958 Beta One. This tracking system 
has demonstrated its ability to acquire as many as three photographs 
of satellites per day over a long period of time, in spite of bad weather 
and mechanical breakdowns. This rate of photography exceeds the 
original expectation by about 50 percent. 
The Moonwatch program, under the supervision of Leon Campbell, 
Jr., depends on 218 teams comprising 5,000 volunteer observers, in the 
United States and abroad. Worldwide interest in the program con- 
tinues, as evidenced by requests for affiliation from groups in North 
and South America, Africa, England, Spain, and the Middle Kast. 
Since the program began, Moonwatch has communicated 9,825 observa- 
tions to the Cambridge headquarters. Arthur S. Leonard, leader of 
the Sacramento, Calif., team obtained improved values for the orbital 
elements of Satellite 1958 Beta One, which was believed “lost.” These 
values led to the recovery of the satellite, which was then photographed 
by the Smithsonian camera stations. 
These unprecedented accomplishments of the satellite-tracking pro- 
grams prompted the executive director of the International Geophysi- 
cal Year to congratulate the Director of the Observatory and his staff, 
on behalf of the U.S. National Committee and the Earth Satellite 
Panel. 
The computation and analysis of optical observations continued 
under the supervision of Richard Adams as chief and Dr. Whitney as 
scientific supervisor. Refinements of techniques and programing 
methods have yielded gratifying results. 
The Cunningham integration methods for the machine programing 
of satellite orbits, together with Dr. Don A. Lautman’s equations for 
the osculating elements, have greatly facilitated the handling of satel- 
lite data and the graphing of perturbations of the orbital elements. 
A limited variety of orbits can be studied at present; for an orbit 
similar to that of Satellite 1957 Alpha the methods show separately the 
perturbational effects of drag and of the earth’s oblateness. 
Drs. Jacchia and Kozai derived new values for the second and fourth 
order coefficients of the earth’s gravitational potential. 
Dr. George Veis has initiated a differential] corrections program 
which is being used to revise the orbits of Satellite 1958 Alpha and 
to obtain accurate elements for all satellites, in particular for 1959 
Alpha One and 1959 Beta One. This program has also produced 
an ephemeris for 1958 Delta Two, during the period September 1958 
to May 1959. 
~ Jack Slowey has developed a program which makes it possible for 
the Baker-Nunn cameras to photograph satellites successfully over a 
long arc. The preliminary results have yielded much valuable in- 
formation, and the Slowey Long-Are Ephemeris will greatly increase 
