322 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 64 



Late in October 1958, observations of Satellite 1958 Alpha had fallen 

 off to such an extent that accurate predictions for the Baker-Nunn 

 stations could not be prepared. Consequently, no Baker-Nunn pho- 

 tographs were being made, and the satellite was in danger of being 

 lost. Twenty-five Moonwatch teams in the United States were asked 

 to make a special effort to find the object and were sent rough predic- 

 tions derived mainly from "best guesses" and extrapolations. Moon- 

 watch observations began to come in again, finally in sufficient number 

 to generate good predictions for the Baker-Nunn stations. There- 

 after the satellite was photographed on a regular basis. The "lost" 

 satellite was found. 



In May of the same year, Professor Arthur S. Leonard, leader of 

 the Sacramento, Calif., Moonwatch team, derived the orbital elements 

 of the carrier rocket of the first Vanguard satellite from observations 

 obtained at Albuquerque, N. Mex., and at Sacramento. These data 

 were then used by the Observatory to make Baker-Nunn predictions 

 that resulted in photographs of the object on May 11 by the station 

 at Organ Pass, N. Mex., and on May 12 by the station in Hawaii. 

 Confirming visual observations were made by Moonwatch teams in 

 China Lake, Whittier, and Walnut Creek, all in California, on 

 May 11. 



One of the most elusive objects was Vanguard I itself, a 6-inch 

 sphere orbiting between 409 and 2,453 miles from the earth. In July, 

 Moonwatch reported that the teams in Yuma, Ariz., and Alamagordo, 

 N. Mex., had observed the satellite passing some 2,000 miles above the 

 earth over a point as much as 1,000 miles south of them. Thereafter, 

 few observations were made of the satellite either by Moonwatch teams 

 or by Baker-Nunn cameras. A special search undertaken by Moon- 

 watch teams in the fall of 1958 failed to locate the satellite. Early 

 the following year. Dr. Henize developed a new search pattern for 

 another attempt. Some 42 Moonwatch teams having special experi- 

 ence and capabilities were selected to participate in the search begin- 

 ning April 1 and to extend for about 6 weeks. The plan utilized 

 a network of teams in pairs separated north and south about 15 

 degrees. The basic idea was to find some search area in the meridian 

 plane of the observing teams through which the satellite must pass 

 within some given time interval and to concentrate the search within 

 this area for the required time so as to ensure that the satellite would 

 not slip through the net. Using an observation made on May 6 by 

 the two Moonwatch teams in Albuquerque, N. Mex., Professor Leon- 

 ard in Sacramento modified the orbital elements of Satellite 1958 

 y82. Using the resulting predictions, his team observed the satellite on 

 May 10. From new predictions several other Moonwatch teams in 

 the West and Southwest were able to observe the satellite, and by May 

 12 the Baker-Nunn camera stations could once more begin to photo- 



