Caroline Lucretia Herschel

German-born English astronomer

• Born: March 16, 1750
• Birthplace: Hanover (now in Germany)
• Died: January 9, 1848
• Place of death: Hanover (now in Germany)

Herschel was an astronomer and mathematician who spent years assisting her better-known brother William Herschel in his astronomical observations. However, she also independently scanned the sky for new objects, discovering two galaxies, several open star clusters, and eight comets. After her brother’s death, she completed the Herschel catalog of twenty-five hundred nebulae, which was included in her nephew John Herschel’s General Catalogue.

Early Life

Caroline Lucretia Herschel (KEHR-eh-lihn lew-KREE-shee-ah HUR-shehl) was the younger of two girls born to Isaac and Anna Ilse Herschel. She also had four brothers as well as three other siblings who died. Isaac, a musician and professor of music, encouraged his children to become educated. As the youngest daughter, Caroline was expected by her mother to do most of the housework, who generally treated Caroline as she would a servant.

When Caroline was seven, her brothers William and Alexander went to England when their regimental band was ordered there and her father fought in the war against France. At age ten, Caroline contracted typhoid fever, which stunted her growth and caused her to stoop slightly. She was only four feet, three inches tall as an adult, and her father predicted that she would likely never marry. In spite of her mother’s attempts to enslave Caroline to domestic duties, her father educated her in music and mathematics and introduced her to astronomy. By 1760 her father had returned from the war, but he remained in poor health until his death in 1767.

In spite of her mother’s attempts to keep her in servitude and after her father’s death, Caroline decided to take more control of her own life and so learned dressmaking, planning to become a governess. Her brother William had been hired as organist in Bath in 1766, and by 1772 he decided to invite Caroline, now twenty-two years old, to live with him. Against her mother’s protests she moved to England, where her brother gave her voice lessons and tutored her in English and mathematics.

She soon began a singing career under her brother’s direction. She was a first soprano singing George Frideric Handel’s Messiah and Judas Macabaeus, among other works, and was often engaged several nights a week. She turned down offers from other directors, reserving her singing for performances directed by her brother. During this time she also began helping William with his telescope projects. She learned to grind and polish lenses and construct the finished telescopes.

Life’s Work

As she learned the skills needed to help William in the shop, Caroline also continued her studies in mathematics, focusing almost exclusively on topics applicable to astronomy, her brother’s growing passion. William’s obsession with his telescopes became so consuming that Caroline sometimes had to feed him while he continued his work, and other times she would read to him to pass the time productively as he laboriously turned yet another lens for a new telescope.

By 1781, William was spending more and more time gazing through his telescopes at the night sky, and Caroline was often by his side taking notes on his observations. In this same year, William made his breakthrough discovery, the planet Uranus. The astronomical community praised his discovery and King George III awarded William an annual salary of œ200. William resigned his position as organist, and soon thereafter Caroline gave up her music career to devote her time to astronomy as well.

As William built ever-larger telescopes and needed increased workspace, he and Caroline moved to larger quarters, first to Clay Hall and then to Slough. Although Caroline spent most of her time assisting her brother by taking records during their nightly observations and doing calculations during the day so the night’s objects could be cataloged, she was still able to find time for her own observations. William encouraged her in this direction. She discovered her first new object on February 26, 1783, an open star cluster in the constellation Canis Major. Over the next several years she discovered more than ten other objects, including a large spiral galaxy and another smaller galaxy.

Caroline also spent a considerable amount of effort sweeping the sky methodically for comets, a common pursuit of amateur and professional astronomers alike. On August 1, 1786, she discovered her first comet, the first comet discovered by a woman. Between 1786 and 1797 she discovered seven more comets. Six of the eight she found in total bear her name. In recognition of her continuing work with her brother, King George III granted her an annual salary of œ50, œ150 less than William. When William married in 1788, Caroline lamented the change in her relationship with her brother. She moved to private lodgings nearby but continued to work with William and in time got along well with his wife, at which point she moved back into William’s home.

After 1797, Caroline devoted most of her effort to other pursuits. In 1798 she published a work that cross-referenced and corrected John Flamsteed’s Historia coelestis Britannica (1725). In addition to revising Flamsteed’s well-known catalog, she added an additional 560 stars to the list. Over the next twenty-five years, until her brother’s death in 1822, Caroline devoted most of her time to helping educate her brother’s son, John, who was born in 1792.

When her brother died she returned to Hanover, resumed her work, and produced the Herschel catalog, listing twenty-five hundred nebulae, many of them discovered by William. The catalog was completed and then published as General Catalogue of Nebulae and Clusters of Stars in 1864 by nephew John.

For her foundational work she received the gold medal in science 1828 from the Royal Astronomical Society. Additional honors followed in 1835, when she was elected an honorary member of the Royal Society, and in 1838, when she was elected to the Royal Irish Academy. In 1846 she received a gold medal in science from the king of Prussia.

During the remaining two years of her life her health gradually worsened. She died on January 9, 1848. Her epitaph, which she composed herself, reads, “The eyes of her who is glorified here below turned to the starry heavens.”

Significance

Caroline Lucretia Herschel’s fame and significance certainly were muted after living and working in William’s more famous shadow. Although she made important astronomical discoveries of her own, those discoveries are not considered comparable in significance to those of William. Separating William’s discoveries from her own, though, may be unfair. The two worked side by side for years, sharing in their work. Without her devotion to William’s work, it is possible that his accomplishments would have been minimized. Certainly he could have worked with a different assistant, but Caroline’s skills were so extraordinary that she could be considered more a colleague than an assistant. She certainly would have had greater opportunities for education if she were born male. Nevertheless, her perseverance enabled her to surmount many of the usual barriers to women’s intellectual advancement. Her brother also helped remove her from the domestic life in which her mother attempted to trap her. Her illness as a child left her disfigured and ruined her chances at marriage, but it also allowed her the time to pursue a career.

Discovering several new objects in the sky and eight comets would have assured any astronomer some degree of fame. What makes Caroline’s work more impressive is that she received recognition as a woman. Caroline Lucretia Herschel represents the first well-known woman astronomer, breaking ground for other women to follow. Her life was commemorated in 1889 with an asteroid bearing her middle name, Lucretia. In 1935 a lunar crater was also named for her.

Bibliography

Herschel, Caroline Lucretia. Caroline Herschel’s Autobiographies. Cambridge, England: Science History, 2003. Contains annotated editions of the two autobiographies penned by Herschel.

Higgins, Frances Lowry. Sweeper of the Skies: A Story of the Life of Caroline Herschel, Astronomer. Chicago: Follett, 1967. A biography of Herschel focusing primarily on her astronomical work.

Hoskin, Michael A. The Herschel Partnership: As Viewed by Caroline. Cambridge, England: Science History, 2003. A biographical work that focuses on the partnership between Caroline and William.

Lubbock, Constance A. The Herschel Chronicle: The Life-Story of William Herschel and His Sister, Caroline Herschel. Cambridge, England: Cambridge University Press, 1933. A biography of William and Caroline with material drawn from their own records.

Wearner, Robert G. Caroline Herschel: First Woman Astronomer. Austin: University of Texas Press, 1989. A biography focusing primarily on Herschel’s astronomical work.