Caroline Lucretia Herschel


Caroline Lucretia Herschel

      Caroline was born in Hannover, Germany on 1750 March 16, and was ultimately one of 10 children. At the age of 10 she was struck with typhus, which subsequently stunted her growth. She never grew taller than 4' 3" and remained frail throughout her life. Her father once told her she would never marry because of her looks and because she was not rich. In addition, primarily because of the times, her mother resisted giving her an education, saying that it was Caroline's duty to take care of her brothers. Despite all of this, Caroline's father secretly educated her and she ultimately displayed musical talent, as well as a gift for mathematics.
      Music was an important part of life for the Herschel family. Caroline's father was a military musician and her older brothers, William and Alexander, as well as Caroline, showed exceptional talent.
      Shortly after the beginning of the Seven Years' War, Hannover slipped into the hands of the French in 1757. Caroline was then 7 years of age and her 19-year-old brother William escaped to England where he became a music teacher. Sometime later he was joined by Alexander and they frequently performed as musicians.
      William moved to Bath, England in 1766 and became organist and choir master at the Octagon Chapel. In 1772, he asked Caroline to come to Bath and she subsequently trained as a singer. Despite her fraility, she was a soprano and gave many successful performances, among which were solo parts in the Messiah and Judas Maccabeus.
      During his time at Bath, William began to study astronomy and mathematics. In 1774, being dissatified with telescopes then available, he began making telescopes to observe the sky. Caroline became his apprentice.
      During one of his surveys of the sky, William discovered what he initially thought was a comet on 1781 March 13. Continued observations by himself and other astronomers of that time soon revealed it as a hitherto undiscovered planet. It was named Uranus. Things began to change for the Herschels.
      William was appointed as astronomer to King George III in 1782 and was granted a royal pension. He immediately gave up his music career and began to practice astronomy full time. Caroline also made a decision at that time and gave up her singing career to become William's assistant.
      William became intrigued by the lists of sky objects discovered and published by the French astronomer Charles Messier. His first order of business was to begin his own survey using bigger telescopes. Not a clear night would pass without William sweeping the sky and Caroline recording his observations. William once commented that Caroline had a way with numbers, and he felt comfortable letting Caroline finalize the observations during the day. She also planned each night's observing schedule. Herschel found the first object of his catalog of nebulae and clusters of stars on 1782 September 7.
      Eager to improve their chances of discovering even more objects, William and Caroline completed the building of a reflector with an aperture of 18.7-inches in 1783 and finally put it to use in October. Prior to that month, William had managed to find a few objects using a small Newtonian sweeper with a focal length of 27-inches.
      Occasions came up when William would have to leave town on business and Caroline began spending more and more time at the telescope. Prior to the completion of the 18.7-inch reflector, she would use the small Newtonian sweeper to look for objects on her own. She found her first object on 1783 February 26, which turned out to be an open cluster that is known today as NGC 2360. Her second object was found on 1783 August 27 and is a galaxy with a modern designation of NGC 205. It had also been noted by Messier back in 1773, but was not then a part of his famous list of objects. It was later designated M110. Caroline found her third object on 1783 September 23. It is a galaxy which is known today as NGC 253. Caroline found other objects in 1783. They were later designated NGC 381, NGC 659, NGC 2548 (M48), NGC 6633, and NGC 7789. In 1784 she found NGC 225, and in 1787 she found NGC 7380. Another object found in 1783 was later designated NGC 2349, but seems to be nonexistent.
      Two moves came in the next few years. First, William moved the observatory to Old Windsor to be closer to the King, and then he moved to Slough, just a short distance from Old Windsor. Caroline's biggest break came in Slough, when on 1786 August 1 she found a comet moving slowly through Leo. William was then in Germany. Caroline suspected this was a comet and observed it again on August 2. She confirmed it had moved, thus proving this was a comet. She wrote letters to various other astronomers announcing her discovery and it was soon observed by astronomers throughout Europe.
      Although William had been aware of Caroline's abilities as an observer for some time, the world had now become aware as well. In 1787 King George III gave Caroline a 50 per year salary to continue as William's assistant and she became the first woman officially recognized for a scientific position.
      William was married in 1788. Although Caroline continued to work as his assistant, she was also doing more independent work. She discovered her second comet on 1788 December 21, which ended up being followed by astronomers until February 5. Later computations revealed the comet moved in a rather long-period orbit, but the exact period was uncertain because of the short observation interval. Interestingly, a comet found by Rigollet in 1939 was found identical to Herschel's 1788 comet. It is now known as periodic comet Herschel-Rigollet and returns every 155 years. Caroline found additional comets on 1790 January 7, 1790 April 18, 1791 December 15, 1793 October 7, 1795 November 7, and 1797 August 14.
      Besides discovering comets, Caroline was also involved in other astronomical pursuits. She began re-cataloging Flamsteed's star catalog and submitted it to the Royal Society in 1798, together with an additional 560 stars which Flamsteed had omitted.
      Following the death of William in 1822, Caroline returned to Hannover and completed William's catalogue of 2500 nebulae. Shortly after its completion, she received the Gold Medal of the Royal Astronomical Society on 1828 February 8.
      Other awards included becoming the first woman to receive honorary membership into Britain's Royal Society in 1835, election into the Royal Irish Academy in 1838, and awarded the Gold Medal for Science by the King of Prussia in 1846.
      Caroline moved back to Hannover late in her life and died on 1848 January 9. Although her father's early prediction that she would be an "old maid" came true, Caroline left an amazing legacy behind as one of the earliest women to break through so many barriers and be recognised for her many accomplishments.
      Caroline wrote her own epitaph, which was engraved on her tombstone upon her death. It reads, "The eyes of her who is glorified here below turned to the starry heavens." In 1889, a minor planet was named "Lucretia" in honor of Caroline's accomplishments.

References

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  12. Osen, Lynn M. Women in Mathematics, MIT Press, 1992.
  13. Pierce, E., Caroline Herschel : Tale of a Comet (1974).
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  15. South, J., An address delivered at the annual general meeting of the Astronomical Society of London on February 8 1829, onpresenting the honorary medal to Miss caroline Herschel, Memoirs of the Royal Astronomical Society 3 (1829), pp. 409-12.
  16. Wolf, W. H.: Memoire and correspondence of Caroline Herschel. 1867.