Karoline Lucretia Herschel was born in Hannover on March 16th, 1750 to her father Isaak Herschel and her mother Anna Ilse Moritzen. Her father Isaak was a military musician, he and his wife had ten children, four died very young. The other five, beside Karoline, were Sophia Elisabeth, born April, 12th 1733; Heinrich Anton Jakob, born November 20st 1734; Friedrich Wilhelm, November, 15th 1738; Johann Alexander, November 13th 1745; and Johann Dietrich, September 13th 1755.
During her youth Karoline had to help her mother with the daily work in the house. The thought to have no other duties than to wash, bleach and iron the tablecloth worried her. She was happy when her brother Wilhelm asked her to come to England for an education as a singer. In the summer of 1772 Wilhelm came to Hannover to help his sister with the travel to Bath. She would see Hannover again fifty years later.
In Bath Wilhelm started to train her as a singer but also teached Karoline in the English language and in mathematics. During breaks and in the evening they talked about the stars. In 1777 she got an invitation to a music festival in Birmingham, but she declined since she would only sing with her brother as conductor. In Bath she most likely sang in the 'Pump Room' and the privately owned Octagon church. These buildings still exists, the latter today (1994) used as a showroom of the Royal Photographic Society.
In 1777 she started to help in the workshop with the grinding of metal mirrors. In the years to come she assisted her brother at the telescope, writing down the observational notes he made while standing at the eyepiece of his telescope. Later, beginning in 1782, she got the annual sum of 50 pounds from King Georg III. for her work assisting her brother, now astronomer at court in Windsor. Leaving Bath for the new place in Datchet near Windsor meant the end of her musical career, but she was happy helping her brother and sharing his astronomical work.
On August, 20th 1782 she started to make own observations with a telescope suitable to find comets. But her time was limited because her main task was assisting her brother with his work. During daytime she managed the household and helped grinding and polishing the metal mirrors.
After moving to Slough in April 1786 Karoline got a newtonian telescope of 27 inch focal length and a magnification of 30. It was placed on a roof, easily accessible from her rooms below. On August 1st, 1786 she wrote to her observation log the data of one hundred nebula and a comet. It was her first comet in a row of eight. Between this year and 1797 she observed five new ones and three others. The comet of November 1795 later was named Encke in honour of his orbital calculations of this comet in 1819.
The comets alone would have made Karolines name famous in astronomy, but she also published a catalog on 561 stars for Flamsteeds atlas and found 14 new nebula during her observations.
On May 8th, 1788 Wilhelm Herschel, at the age of 50, married Mrs. Mary Pitt, widow in Upton. This changed the life of Karoline completely. She no longer had to look after the household and moved to a flat in Slough. Her duties as astronomical assistant to her brother were not affected. The following 34 years were filled with writing down Wilhelms papers, doing calculations, grinding mirrors and making own observations.
After the death of her brother on August, 25th 1822, she went back to Hannover, Germany, fifty years after she left this town for Bath. Word spread fast of her being back in Hannover, and she was visited by Gauss, A. von Humbold, Maedler and others. Beside other honours she received the gold medal of the Royal Astronomical Society in 1828 and was announced Fellow of the RAS in 1835, in 1838 she was asked to join the Academy of Science in Dublin and in 1846 she received the gold medal of the Prussian Academy of Science with a letter written by Alexander von Humbold. Writing letters she kept contact to her nephew John Herschel and paid much interest to his observations. In one letter she mentioned to join him for his expedition to South Africa, if she had been 30 or 40 years younger. John visited his aunt in Hannover, the last time in 1838 with his son William James, then aged 8.
Karoline Lucretia Herschel died January, 9th 1848, aged 98. She is buried at the cemetery of the 'Gartengemeinde' in Hannover, Marienstrasse 35.
References: 1. BUTTMANN, G., Wilhelm Herschel, WVG Stuttgart 1961