First a housekeeper and singer for the organist William, she became his general assistent, and engaged in astronomy together with William. Most of her astronomical work was helping William by writing down his observations, but besides that work, Caroline was observing on her own, notably with a 27-inch focal length Newtonian 'sweeper.' She discovered a number of deepsky objects in the time of 1783-87, notably an independent discovery of M110 (NGC 205), the second companion of the Andromeda Galaxy. Caroline stated to have observed 14 objects until the end of 1783 alone, see Mary Herschel (1876), p. 52, or G. Buttmann (1961), p. 64:
"[..] I knew too little of the real heavens to be able to point out every object so as to find it again without losing too much time by consulting the Atlas. But all these troubles were removed when I knew my brother to be at no great distance making observations with his various instruments on double stars, planets, &c., and I could have his assistance immediately when I found a nebula, or cluster of stars, of which I intended to give a catalogue; but at the end of 1783 I had only marked fourteen, when my sweeping was interrupted by being employed to write down my brother's observations with the twenty-foot. [..]"The obeservations of Caroline are discussed to more depth by Hoskin (2005). Between 1786 and 1797, she discovered a total of eight comets.
.. more to come soon ..
Caroline Herschel was honored lately by the astronomical community by naming a Lunar Crater after her: C. Herschel (34.5N, 31.2W, 13.0 km diameter, 1935). Asteroid (281) Lucretia was named to honor Caroline Lucretia Herschel; it had been discovered on October 31, 1888 by J. Palisa in Vienna.
Caroline Herschel's Comet Discoveries:
1786 Aug 1 C/1786 P1 1786II Herschel 1788 Dec 21 35P/1788 Y1 1788II P/Herschel-Rigollet 1790 Jan 7 C/1790 A1 1790I Herschel 1790 Apr 18 C/1790 H1 1790III Herschel 1791 Dec 15 C/1791 X1 1792I Herschel 1793 Oct 7 C/1793 S2 1993I Messier (Sep 27) 1995 Nov 7 2P/1795 V1 1795 P/Encke 1797 Aug 14 C/1797 P1 1797 Bouvard-Herschel-LeeComet P/Herschel-Rigollet was discovered again by Roger Rigollet in 1939, and Leland E. Cunningham found within a week that this was probably identical to the comet observed by Caroline Herschel in 1788. This comet has a period of about 155 years and is expected to return in 2092.
Comet P/Encke had been previously seen when it had been discovered by Pierre Méchain on its 1786 apparition, and again on its later returns in 1805 and 1818, discovered by Pons on both occasions, before Johann Franz Encke, in 1819, could demonstrate that it is short-periodic and returns about every 3.3 years, the second periodic comet discovered, and the shortest period found to date.
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