The Inimitable Caroline
The sister of British astronomer William Herschel was herself a capable and pioneering celestial observer
"I Am Hooked!"
Herschel was still completely unknown in astronomical circles, so that early announcements of his discovery carried many misspellings of his name, and there was general misapprehension as to who he was. Still, as the finder it was his right to name the new planet. He decided to name it Georgium Sidus ("George's Star") after the king of England, young George III. (Never popular with foreign astronomers, the name was changed to Uranus, a Latinized version of the Greek god Ouranos, in the years after Herschel's death.). The King already had a former tutor who served as the King's Astronomer (as distinct from the Astronomer Royal, the latter being defined as the head of the Royal Observatory at Greenwich), but that person was elderly and in the background. In fairly short order, thanks mostly to friends in high places, William was invited to become the King's Astronomer.
It was a mixed blessing. The new position meant a reduction in income and required the Herschels to live near the palace and be available on any clear night the King felt like being entertained astronomically. However, it allowed William to pursue astronomy without distraction. And so the professional musical careers of both William and Caroline came to an end. They moved house to be close to the King at Windsor Castle, and William soon developed a thriving telescope-making business that enabled him to continue his nighttime observations. Caroline managed the flow of data, reducing each night's observations to a usable form, making legible copies and often carrying it to London for publication. This being the 18th century, she was also responsible for keeping house and providing meals.
One pictures the brother and sister in their small house eating dinner, only to have a knock on the door reveal some lackey announcing that the King and his entourage would be arriving shortly at the Herschel house to be entertained by the view through the new 40-foot telescope. (Forty feet referred to the instrument's focal length, not its aperture, as it would in today's terminology.) This remarkable instrument had been paid for by the King, who felt no hesitation demanding its use. On one such occasion, the royal party included the elderly Archbishop of Canterbury, who viewed the huge telescope with its ladders and struts with some consternation. As the story goes, the enthusiastic King held out a helping hand to the Archbishop and cried, "Come, my Lord Bishop, I will show you the way to Heaven."
Caroline soon began to pursue her own observations. William built a telescope for her that was smaller than the massive 40-footer, but powerful enough for her to discover a number of comets. More importantly, she joined him in sweeping the skies for nebulae. Through their individual efforts, the number of known nebulae grew from about 100 to more than 2,500 by the time they finished.
At other times Caroline assisted with the big telescope. On a bitterly cold night at the end of 1783,
"My brother . . . directed me to make some alteration in the lateral motion, which was done by machinery. . . . At each end of the machine . . . was an iron hook such as butchers use for hanging their joints upon, and having to run in the dark on ground covered a foot deep with melting snow, I fell on one of these hooks which entered my right leg about 6 inches above my knee; my brother's call "Make haste!" I could only answer by a pitiful cry "I am hooked." He and the workman were instantly with me, but they could not lift me without leaving nearly 2 oz. of my flesh behind. The workman's wife was called but was afraid to do anything, and I was obliged to be my own surgeon."
In 1788 when she was 38, Caroline's life fell apart. William, nearly 50, married a rich widow, upsetting the collegial relationship between the two siblings. The bride, it seems, made considerable effort to soothe and placate her new sister-in-law, but to no avail. Caroline soon moved to new lodgings and began a new journal to express her feelings. Many years later, when she finally made peace with herself, she destroyed every page of that journal and adopted a much more benign view of her sister-in-law. But even prior to this reconciliation, Caroline took great delight in her young nephew, William's son John. Nevertheless, when William died in 1822, she immediately left England and returned to Hanover, a decision she later regretted. Her good spirits returned, however, and she lived to the remarkable age of 98, her mind lively to the end.
- Hoskin, M. 2003. The Herschel Partnership: As Viewed by Caroline. Cambridge: Science History Publications, Ltd.
- Hoskin, M., ed. 2003. Caroline Herschel's Autobiographies. Cambridge: Science History Publications, Ltd.