On 29 June 1985 King Juan Carlos of Spain inaugurated the international observatory at the Roque de los Muchachos, high on the volcanic island of La Palma in the Canaries. He was accompanied by his family, the heads of state of all but one of the participating nations, the Queen of Denmark, King of Sweden, Queen of the Netherlands, President of Ireland and President of West Germany. The United Kingdom was represented by the Duke and Duchess of Gloucester. The presence of these monarchs and presidents raised questions of precedence, including that of the way their flags should be flown. The solution was simple, not to fly the flags at all. Instead a well known local artist César Manrique was commissioned to design the Flags of the Undiscovered Planets. Here are three of the designs, brought back and donated to the Institute by Sir John Kingman, who had been present as Chairman of the Science and Engineering Research Council.