Peter Paul Rubens, Flemish painter (Siegen, 1577 - Antwerp, 1640), leading exponent of the Baroque period.
The canvas depicted on this stamp measures 181 x 244 cm and is kept in the Prado Museum. It alludes to the Greek myth of the origin of the Milky Way: Heracles (Roman Hercules), the love child of Zeus (Roman Jupiter) and a mortal, Alcmene, is taken at the age of 8 months to suckle the goddess Hera (Roman Juno, wife of Zeus-Jupiter) while she sleeps, in order to make him an immortal god; Hera wakes with a start, pushes him away and a jet of milk escapes into the firmament, creating the Milky Way (needless to say, Hera had already tried to kill the bastard son of her unfaithful husband).
A sketch of the same canvas, entitled Juno suckling Hercules, 26.5 x 34 cm, is in the Royal Museums of Fine Arts, Brussels.