It was a space problem of sorts for the new British prime minister: where to put the minuscule sample of the lunar dust that America’s Apollo 11 astronauts had scooped from the surface of the moon in their giant leap for mankind?

The answer was a cupboard in the prime minister’s residence at 10 Downing Street, where the four moon specks, a gift to Britain from the United States, languished for several years in the 1970s.

The moon dust’s fate was revealed recently by the British National Archives, which released 178 pages of correspondence on the subject from the prime minister’s office dating back 30 years.