Spacecraft News The Remarkable Syncom

Press, Volume CII, Issue 30286, 12 November 1963, Page 24

Spacecraft News The Remarkable Syncom

Somehow, the communications satellite Telstar caught the public eye. Perhaps there was some magic in its name, or maybe the publicity it received by being the first comsat to relay live TV between continents was responsible. Much less has appeared in print concerning another comsat, Syncom 11, which has probably made a more significant contribution to world communications than either or both of the Telstars. In the first place Syncom 11, from its hovering position 22,300 miles above Brazil, is capable of linking the old world and the new for a full 24 hours every day, unlike the Telstars which are available for only 20 minutes at a time. Since it was placed in orbit iast July, Syncom II has accumulated more message-handling time than all other comsats put together. Another advantage of Syncom is that its high orbit permits very long communications links, such as, for example, recent microwave telephone conversations between California and Nigeria, a distance of 7700 miles. Although Syncom can only be used for very limited television transmissions it has proved the practicability of high - altitude synchronousorbit satellites and paves the way for the Advanced Syncom, now under development, which will permit continuous TV links between continents. Both Syncoms are produced by the Hughes Aircraft Company—an aircraft company which builds no aircraft. The outstanding achievement of Syncom II has been the precision control of its orbit. Syncom is orbiting around the earth in perfect synchronism with the earth’s rotation, a state of affairs resulting from numerous spurts of thrust

from control jets following the firing of a rocket motor on board the satellite which converted its orbit from an ellipse to a circle'. A measure of the orbital precision is the fact that the difference between the highest and lowest points of Syncom’s orbit is less than 10 miles—an accuracy of better than one part in 2500.