America had been forced to play a catch-up role following the Soviet Union's preemptive strike with Sputniks 1 and 2, but this did not mean that the USSR was resting on its laurels. The West's habit of publishing scientific results in the open literature, coupled with America's wish to portray its capabilities in the emerging field of space science, produced immediate improvements in Soviet spacecraft.

An attempt was made on 27 April 1958 to launch what the Soviets called Object D , but resonant vibrations in the launch vehicle caused it to break up and the satellite was lost ^[26]. When the third artificial satellite , later named Sputnik 3, reached orbit on 15 May 1958, it incorporated two technological features which first appeared on American satellites. The first was a complement of instruments to detect the Van Allen belts discovered by Explorer 1; the second was a solar energy collection system ^[33]. Given the former aggressive launch policy of the Soviets, and the fact that six months had passed since the launch of Sputnik 2, it seems likely that Sputnik 3 was delayed to fit these instruments ^[34].

Figure 3.7: The United Kingdom's Jodrell Bank radio telescope was used to track many of the early spacecraft, including the Sputniks, since it was larger and more sensitive than any other deep space antenna of the time [Mark Williamson]

Continuing the Soviet trend towards ever larger spacecraft, Sputnik 3 was a 3m high aluminium-alloy cone measuring 1.73 m...