Caroline Lucretia Herschel ( , ; 16 March 1750 – 9 January 1848) was a German astronomer, whose most significant contributions to astronomy were the discoveries of several comets, including the periodic comet 35P/Herschel–Rigollet, which bears her name. She was the younger sister of astronomer William Herschel, with whom she worked for most of her career.

She was the first known professional female astronomer, and the first woman to receive a salary as a scientist, and the first woman in England to hold a government position. to be awarded a Gold Medal of the Royal Astronomical Society (1828), and to be named an honorary Member of the Royal Astronomical Society (1835, with Mary Somerville). She was named an honorary member of the Royal Irish Academy (1838). The King of Prussia presented her with a gold medal for Science on the occasion of her 96th birthday (1846).

Early life

Caroline Lucretia Herschel was born in the town of Hanover, Germany on 16 March 1750. She was the eighth child and fourth daughter of Isaac Herschel (1707–1767), a self-taught oboist, and his wife, Anna Ilse Moritzen (1710–1789). The Herschel family originated from Pirna in Saxony, near Dresden. Isaak became a bandmaster in the Hanoverian Foot Guards, whom he first joined in 1731, and was away with his regiment for substantial periods. He became ill after the Battle of Dettingen (in the War of the Austrian Succession) in 1743 and never recovered fully; he suffered a weak constitution, chronic pain, and asthma for the remainder of his life. The oldest of their daughters, Sophia Elizabeth Herschel (1733–1803), was sixteen years older, and the only surviving girl besides Caroline. She married violinist Joachim Heinrich Griesbach (1730–1773) when Caroline was five, which resulted in the younger girl being tasked with much of the household drudgery. than be educated in accordance with her father's wishes. However, her father sometimes took advantage of her mother's absence by tutoring her individually, or including her in her brother's lessons, such as violin. Caroline was briefly allowed to learn dress-making. Though she learned to do needlework from a neighbour, her efforts were stymied by long hours of household chores. To prevent her from becoming a governess and earning her independence that way, she was forbidden to learn French or needlework any more advanced than the skills she could pick up from neighbours. of running William's household, and began learning to sing. She became the principal singer at his oratorio concerts, and acquired such a reputation as a vocalist that she was offered an engagement for the Birmingham festival after a performance of Handel's Messiah in April 1778, where she was the first soloist. She declined to sing for any conductor but William, and after that performance, her career as a singer began to decline. Caroline was subsequently replaced as a performer by distinguished soloists from outside the area because William wished to spend less time in rehearsals to focus on astronomy.

Astronomical career

First discoveries and catalogue

thumb|upright|A telescope that William Herschel made for Caroline 1795

William's interest in astronomy started as a hobby to pass time at night. At breakfast the next day he would give an impromptu lecture on what he had learned the night before. Caroline became as interested as William, stating that she was "much hindered in my practice by my help being continually wanted in the execution of the various astronomical contrivances." She learned to copy astronomical catalogues and other publications that William had borrowed. She also learned to record, reduce, and organize her brother's astronomical observations. She recognized that this work demanded speed, precision and accuracy.

Caroline was asked to move from the high culture of Bath to the relative backwater of Datchet in 1782, a small town near Windsor Castle where William would be on hand to entertain royal guests. He presumed that Caroline would become his assistant, a role she did not initially accept. She was unhappy with the accommodations they had taken; the house they rented for three years had a leaky ceiling and Caroline described it as "the ruins of a place". She was also aghast at the prices in the city and the fact that their domestic servant was imprisoned for theft at the time of her arrival. While William worked on a catalogue of 3,000 stars, studied double stars, and attempted to discover the cause of Mira's and Algol's variability, Caroline was asked to "sweep" the sky, meticulously moving through the sky in strips to search for interesting objects. She was unhappy with this task at the beginning of her work, longing for the culture of Bath and feeling isolated and lonely, but gradually developed a love for the work. "Comets and Letters", and "Books of Observations". This, along with two subsequent books, currently belong to the Herschel trove at the Royal Astronomical Society in London.

On 26 February 1783, Caroline made her first discovery: she had found a nebula that was not included in the Messier catalogue. That same night, she independently discovered Messier 110 (NGC 205), the second companion of the Andromeda Galaxy. William himself then began to search for nebulae, sensing that there were many discoveries to be made. Caroline was relegated to a ladder on William's 20-foot reflector, attempting impossible measurements of double stars. William quickly realized his method of searching for nebulae was inefficient and he required an assistant to keep records. Naturally, he turned to Caroline.

In the summer of 1783, William finished building a comet-searching telescope for Caroline, which she began to use immediately. Five of her comets were published in Philosophical Transactions. A packet of paper bearing the superscription, "This is what I call the Bills and Receipts of my Comets" contains some data connected with the discovery of each of these objects. William was summoned to Windsor Castle to demonstrate Caroline's comet to the royal family. William recorded this phenomenon, himself, terming it "My Sister's Comet." Caroline Herschel is often credited as the first woman to discover a comet; however, Maria Kirch discovered a comet in the early 1700s, but is often overlooked because at the time, the discovery was attributed to her husband, Gottfried Kirch. The third comet was discovered on 7 January 1790, and the fourth one on 17 April 1790. She announced both of these to Sir Joseph Banks, and all were discovered with her 1783 telescope.

In 1797 William's observations had shown that there were a great many discrepancies in the star catalogue published by John Flamsteed, which was difficult to use because it had been published as two volumes, the catalogue proper and a volume of original observations, and contained many errors. William realised that he needed a proper cross-index to properly explore these differences but was reluctant to devote time to it at the expense of his more interesting astronomical activities. He therefore recommended to Caroline that she undertake the task, which ultimately took 20 months. The resulting Catalogue of Stars, Taken from Mr. Flamsteed's Observations Contained in the Second Volume of the Historia Coelestis, and Not Inserted in the British Catalogue was published by the Royal Society in 1798 and contained an index of every observation of every star made by Flamsteed, a list of errata, and a list of more than 560 stars that had not been included.

In his book The Age of Wonder, Richard Holmes is more sympathetic to Caroline's position, noting that the change was in many respects negative for Caroline. With the arrival of William's wife, Caroline lost her managerial and social responsibilities in the household and accompanying status. She also moved from the house to external lodgings, returning daily to work with her brother. She no longer held the keys to the observatory and workroom, where she had done much of her own work. As she destroyed her journals from 1788 to 1798, her feelings about the period are not entirely known. In August 1799, Caroline was independently recognized for her work, when she spent a week in Greenwich as a guest of the royal family.

Later life and legacy

thumb|1847 lithograph of Caroline Herschel around 97 years of age

Caroline continued to assist William with his observations but her status had greatly improved from the housekeeper she had been in her young days. She was the guest of Maskelyne at the Royal Observatory in 1799 and a guest of members of the Royal Family at various times in 1816, 1817 and 1818.

After her brother died in 1822, Caroline was grief-stricken and moved back to Hanover, Germany, continuing her astronomical studies to verify and confirm William's findings and producing a catalogue of nebulae to assist her nephew John Herschel in his work. However, her observations were hampered by the architecture in Hanover, and she spent most of her time working on the catalogue.

The Royal Astronomical Society elected her an honorary member in 1835, along with Mary Somerville; they were the first female members. She was also elected as an honorary member of the Royal Irish Academy in Dublin in 1838. and the crater C. Herschel on the Moon is named after her. The open clusters NGC 2360 (Caroline's Cluster) and NGC 7789 (Caroline's Rose) are unofficially nicknamed in her honour. On 6 November 2020, a satellite named after her (ÑuSat 10 or "Caroline", COSPAR 2020-079B) was launched into space.

Adrienne Rich's 1968 poem "Planetarium" celebrates Caroline Herschel's life and scientific achievements. Judy Chicago's 1969 artwork The Dinner Party, which celebrates historical women who have made extraordinary contributions, features a place setting for Caroline Herschel. Google honoured her with a Google Doodle on her 266th birthday (16 March 2016).

Poet Jessy Randall's 2022 collection Mathematics for Ladies includes a poem honoring Herschel.

In 2023, the 57 densely handwritten pages of her diary were put on display in the music room of the Herschel Museum of Astronomy in Bath, the same place that Herschel resided. The documents cost the museum £108,000, making it by far the institution's most expensive acquisition. Her earned salary from King George III made her the first known professional female astronomer. The diary documents her life in the years 1755 to 1775, the years of Herschel's childhood in Hanover in a large family which produced an ample number of musicians, and leading up to her first years living in Bath.

In 2024, UK musician and singer-songwriter Jay Anderson released the single 'Moving' on Real Kind Records, a song dedicated to the life and times of Caroline Herschel. He filmed a live acoustic version of the song at The Herschel Museum in Bath, sat in the old music room where Caroline and her brother used to rehearse for local concerts.

See also

  • Timeline of women in science

References

Footnotes

Citations

Sources

Further reading

  • Caroline Lucretia Herschel biography at fembio.org
  • Caroline Herschel Biography, SEDS
  • Caroline Herschel's Deepsky Objects, SEDS
  • About the Herschel Museum of Astronomy
  • Obituary of Miss Caroline Lucretia Herschel. Monthly Notices of the Royal Astronomical Society, Vol. 8, p. 64 (1847).
  • Digitised papers relating to Caroline Herschel and her work, including letters from her, in the Board of Longitude archive in Cambridge Digital Library
  • Catalogue of Stars (London, 1798)