numbering is still the most commonly used identifying label for these celestial landmarks. He discovered NGC 12, NGC 13, NGC 14, NGC 16, NGC 23, NGC 24, NGC 7457 (work in progress). Works with his sister Caroline Herschel Following the death of their father, William suggested that Caroline join him in Bath, England. In 1772, Caroline was first introduced to astronomy by her brother. Caroline spent many hours polishing the mirrors of high performance telescopes so that the amount of light captured was maximized. She also copied astronomical catalogues and other publications for William. After William accepted the office of King's Astronomer to George III, Caroline became his constant assistant. In October 1783, a new 20-foot telescope came into service for William. During this time, William was attempting to observe and then record all of the observations. He had to run inside and let his eyes readjust to the artificial light before he could record anything, and then he would have to wait until his eyes were adjusted to the dark before he could observe again. Caroline became his recorder by sitting at a desk near an open window. William would shout out his observations and she would write them down along with any information he needed from a reference book. Caroline began to make astronomical discoveries in her own right, particularly comets. In 1783, William built her a small Newtonian reflector telescope, with a handle to make a vertical sweep of the sky. Between 1783 and 1787, she made an independent discovery of M110 (NGC 205), which is the second companion of the Andromeda Galaxy. During the years 1786–1797, she discovered or observed eight comets. She found fourteen new nebulae and, at her brother's suggestion, updated and corrected Flamsteed's work detailing the position of stars. She also rediscovered Comet Encke in 1795. Caroline Herschel's eight comets were published between 28 August 1782 to 5 February 1787. Five of her comets were published in Philosophical Transactions of the Royal Society. William was even summoned to Windsor Castle to demonstrate Caroline's comet to the royal family. William recorded this phenomenon himself, terming it "My Sister's Comet." She wrote letters to the Astronomer Royal to announce the discovery of her second comet, and wrote to Joseph Banks upon the discovery of her third and fourth comets. The Catalogue of stars taken from Mr Flamsteed's observations contained an index of more than 560