Visions of the Universe cover, 'The Launch of Explorer I' Prestige Booklet Pane, London W1 Postmark

Visions of the Universe cover, ‘The Launch of Explorer I’ Prestige Booklet Pane with 2^nd class Enceladus has geysers of water ice and vapour, 1^st class Black holes are super-dense regions of space, £1.55 Gravitational lensing occurs when gravity bends light & £1.60 Cygnus A Galaxy is a powerful source of radio waves stamps and London W1 first day of issue postmark dated 11 February 2020