Isaac Herschel, an oboist in the Hanoverian Foot Guards Band, a military band in Hanover, Germany, and his wife Anna raised a large and close knit family in a very modest environment in the early 1700’s. Though a musician by profession, Isaac had a variety of interests including math, science, and astronomy to which he exposed his children. His son Friedrich Wilhelm, born in 1738, was very receptive to this stimulation and eager to learn. His aptitude for learning led him to become quite vocal and argumentative and sometimes heated philosophical discussions in the Herschel house began at dinnertime and dragged on into the night.
Friedrich Wilhelm also became an oboist and violinist in the same band as his father. His older brother Jacob and sister Caroline were also musically inclined. But enlisting in the military band required that band members follow the infantry into battle. After a series of transfers and relocations due to the Seven Years War, Friedrich Wilhelm, at 19 decided to abandon the band and quietly moved to England. He anglicanized his name to Frederick William (known as William) and set up a music business with Jacob. He missed his family, especially Caroline, then a household drudge back in Hanover. William sent for Caroline to join him in England; she was eternally grateful.
Caroline had despaired of having a meaningful life. She contracted small pox (some sources say typhus) as a child causing disfiguration in her body. But William, a compassionate man, was always willing to keep her company. Giving up a singing career, Caroline became a housekeeper and assistant to William, now a performer, composer, and tutor.
William pursued music with fervor, a workaholic by nature; his music influenced by the German composer, Franz Joseph Haydn. (A few of his compositions can be found on Youtube and are really quite pleasant listening). Herschel was indeed a contemporary of Mozart and wrote several symphonies. Despite his success and accomplished composing, he felt unchallenged in his musical career and at age 35 began looking for diversions.
Remembering his exposure to astronomy as a child, William bought a book on optics by Isaac Newton, apparently very well written and piquing his interest. He rented telescopes and spent many hours observing the night skies even though music was a full time job.
In 1781, eight years after becoming an amateur astronomer he observed a large apparent disk in the constellation Gemini. A few days later the disk had changed position and William thought he had found a comet. After announcing his discovery it was determined by other astronomers that the object was really a planet. He called it “Georgium Sidus” (George’s Star) after King George III of England. Though George III was also an amateur astronomer, continental scientists convinced William to change the name to a classical deity, Uranus.
Invigorated, Herschel began building his own telescopes, not satisfied with the ones he rented. Possessing exceptional patience and endurance he ground mirrors for weeks before succeeding in making a 5 inch reflector on his 200th attempt. The cost of building large ones, however, was still a bit beyond his means. He succeeded in creating a 20 foot focal length telescope with which he did most of his important work. Making telescopes was not always a dull process. In one occurrence William, Jacob, and several assistants were pouring a cast when the mold suddenly broke. Molten metal spilled onto the cold wet floor and spattered in all directions sending the men scrambling. William tripped and fell on a pile of bricks. His telescopes were arguably the best in the world at that time; certainly among the largest. He built a 40 foot, 48 inch diameter telescope that was cumbersome and awkward to use requiring several men to move it. The mirror also distorted under its own weight. When the instrument was almost finished William could not contain himself and climbed up to the not yet completed observing platform. The supports collapsed and William fell, injuring himself. Caroline later was also seriously injured when she caught herself on a large hook while descending from the platform. William, oblivious of her predicament, still shouted orders to her as she struggled.
Herschel began a systematic study on the construction of the heavens. In 1782 he published the first double star catalog; not all were binary stars, just stars that appeared close together. His career in music also ended that year. In 1784 he conducted an investigation concerning the structure of the Milky Way and concluded, incorrectly, that the solar system was located somewhere in the center of the vast conglomeration of stars. Herschel, like other astronomers, sometimes jumped to conclusions. In 1788 he married a wealthy widow of a brewer, Mary Pitt (to the chagrin of Caroline) and could now afford to build even larger and more precise telescopes. They had one son, John, who is also recognized in history as an accomplished astronomer. Mary and Caroline eventually became friends and convinced William to take a holiday from time to time. Caroline would carry on the observations in his absence. In 1789 he published his nebula classification and in 1800 discovered infrared rays in the solar spectrum.
Most of William Herschel’s accomplishments were from his tireless efforts and ability to go without sleep. Caroline would write of his habit of dashing out of concerts during intermissions to take advantage of clear skies. His discovery of Uranus is no doubt due to the amount of time he spent observing. He was knighted in 1816 and recognized as one of the greatest stellar observers. He died in 1822 at age 84.
Caroline became an accomplished astronomer, as well, discovering at least six comets and becoming an excellent lens grinder. She organized and kept her brother’s records for almost 50 years. She died in 1848 at age 98. A crater on the moon in Mare Imbrium is named in her honor.
(This article was first published in the Johnson Space Center Astronomical Society newsletter Starscan 1988 by Jan W. Railsback; modified for 2010).
Sources and recommended reading:
1. The Discovery of Our Galaxy, by Charles A. Whitney
2. Astronomers Royale, by Colin A. Ronan
3. The Astronomers, by Colin A. Ronan
4. The History of Astronomy from Herschel to Hertzprung, by Dieter B. Herrmann
5. The Star Lovers, by Robert S. Richardson