Complex sentence: In Britain the Sputnik crisis was much less visible and reaction to the launch suggested an appreciation of the novelty of the space age, but became part of the Cold War narrative when the Soviets launched a dog into space in November 1957.
Split into simpler sentences: In Britain the Sputnik crisis was much less visible and reaction to the launch suggested an appreciation of the novelty of the Space Age. It eventually became part of the Cold War narrative when the Soviets launched a dog into space in November 1957.