Tonight is the annual Twilight at the Museums, where the consortium of Cambridge museums stays open to the witching hour of, um, half past seven (visit
the webpage, here).
Never mind. It is a nice idea, a little transgressive (museums are day-time places designed for rational enquiry), and a little magical (museums are repositories of significant objects in talismanic arrangements which, viewed by night, etc. etc.).
And what better emblem of this marriage of the rational and the arcane, the cerebral and the eerie, than William Herschel’s telescope, at the Whipple Museum of the History of Science.
William Herschel was the great Germano-British astronomer (and musician – he was in his youth a notable composer and performer on the oboe) who discovered the planet Uranus in 1781. He also identified various of the clouds of dust in the Messier catalogue as star clusters, discovered in turn over 2,400 deep-sky objects which he identified as ‘nebulae’ (many of which would later and more properly be identified as galaxies by Edwin Hubble), made a systematic catalogue of binary stars, and discovered various small moons of Saturn and Uranus.
He also designed and made his own telescopes, so-called Herschelian telescopes, over four hundred of them, the largest with a forty-foot focal length and a 49.5 inch primary mirror. He gave one of his creations to his sister, Caroline, and she went on to discover various heavenly bodies, notably eight comets.
In truth, Hershel’s connection with Cambridge was nodding at best. He was born in Hanover, lived in Bath, and died in Slough. However, it was the acquaintance of a former professor of Mathematics at Cambridge, the Rev. John Michell, made through their shared musical interests, which stimulated his enthusiasm in astronomy. And the Whipple has one of his telescopes. So I’m claiming him.