As I’ve sorted through the many intricacies and surprises associated with double stars over the last several years, I’ve accumulated a stellar amount of respect for the remarkable efforts of our 18th and 19th century forerunners. They not only literally labored in the dark, but figuratively as well.
Consider William Herschel’s mirrors with speculum coatings, the 3.9 inch refractor used by James South and John Herschel in the heart of smokey London for their 1824 catalog, the bifilar micrometers used by all of them to measure position angles and separations that were illuminated first with candles and later with kerosene lamps, the absence of comprehensive printed double star catalogs, and of course, lengthy communication times, limited research facilities, and no fancy electronics. Nevertheless, they persisted out of sheer dedication and love for the endeavor, coaxing unbelievable performances from crude instruments — performances that many of us have great difficulty coaxing from vastly improved instruments.
The one 19th century observer I consistently run into time after time during my double star excursions is Sherburne Wesley Burnham, whose name is associated with approximately 1500 double star discoveries. I’ve learned not only to respect and admire his observations, but I repeatedly turn to the many publications he left behind when I’m searching for information about observations made by his predecessors or associates. So when Neil English, author of numerous books on astronomy, recently asked if I would like to join him in writing an essay on Burnham, I didn’t hesitate. You can read our combined effort on his web site, which can be found at this link.
Enjoy the essay, and Clear Skies! :cool:
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