Book of the Week (27th February 2012)

Selenographia, sive Lunae Descriptio by Johannes Hevelius (1647)

Johannes Hevelius (1611-1687) was a German-Polish brewer, town councillor and astronomer.  Although he played a leading role in the government of Danzig throughout his working life, Hevelius loved to study the night sky.  He built his own observatory and acquired the very best astronomical instruments.  Between 1641 and 1647 he charted the topography of the moon’s surface, publishing the results in his Selenographia of 1647.  His engravings were so detailed and accurate that it was over 200 years before the next significant development in lunar mapping occurred when, during the ‘Space Race’, US and Soviet agencies vied to be the first to glimpse the far side of the moon.  Hevelius went on to discover four comets, and write further treatises on stars and the movement of heavenly bodies.  In 1679 his observatory was destroyed by fire, and he lost his precious notes and instruments.  The astronomer never fully recovered from the shock; although he rebuilt the observatory and refurnished it, he did not live to see the publication of his complete celestial map in 1690.

The Cathedral Library has a splendid edition of Hevelius’s Selenographia, printed in Danzig in the mid-seventeenth century.  Its frontispiece shows the figure of ‘Contemplatio’ holding a telescope.  The sun appears to her right and the moon to her left.

Inside the book there are engravings of Hevelius’s instruments, including this one of the telescope on the roof of his observatory.

The detail in the map of the lunar surface is outstanding for its time.  In addition to his topographical studies, Hevelius also charted the phases of the moon.