The BBC World Service Radio Witness History podcast Laika, the first dog in space contains a short audio clips from some vintage 1950's British news. At
02:30 in a recording replete with exciting music in the background is heard to say:
Sputnik the second has been launched. A multi-stage rocket with a fuel more powerful than anything the West has in stock, put its final stage into around-the-world orbit.
Two things are astonishing about Sputnik the second; its weight, more than half a ton, and its live passenger Laika the most famous husky in the world, or strictly speaking, (unclear final word).
The narrator goes on to explain that Laika was incorrectly identified as a husky.
Question: What "fuel more powerful than anything the West (had) in stock" put Laika in orbit aboard Sputnik 2?