America had barely recovered from the launch of Sputnik 1 when, just 1 month later, on 3 November 1957, the Soviet Union did it again. The second Sputnik was a much larger vehicle: its total mass was 508.3 kg, six times that of Sputnik 1. What was not widely realised at the time, however, was that the Sputnik 2 spacecraft remained attached to the central core stage of its launch vehicle, the two being thrown into orbit together. This meant that the total mass injected into orbit was some six-and-a-half tonnes ^[18], a staggering capability to those who realised it. That, however, was only part of Sputnik 2's achievement.

To the amazement of a world already fascinated or, in many cases, frightened by the advent of Sputnik 1, Sputnik 2 delivered a dog called Laika to orbit, thus arguably opening the field of veterinary space science. If Sputnik 1 had conducted science by default, Sputnik 2 was a true space science platform. In addition to its radio transmitter and a pressurised cabin for Laika, it carried a package of solar UV and X-ray detectors, mounted on a frame within the nosecone, and a cosmic ray experiment mounted on the body of the rocket itself.

The solar radiation experiment consisted of three photo multipliers mounted 120 apart and equipped with filters to separate the X-ray bands and the hydrogen line in the solar UV spectrum ^[19]. Photons striking the photo multiplier tubes produced electrical signals which were...