Caroline Herschel: Assistant Astronomer or Astronomical Assistant?

A convenient introduction to the work of Hevelius is the article in Dictionary of scientific biography.

Clerke Agnes , The Herschels in modern astronomy (London, 1895), 139.

Sidgwick J. B. , William Herschel: Explorer of the heavens (London, 1953) remains the best overall introduction to Herschel's work. The Herschel chronicle: The life-story of William Herschel and his sister Caroline Herschel (Cambridge, 1933; hereafter Chronicle), ed. by a descendent of William, Lubbock Constance A. , and Memoir and correspondence of Caroline Herschel, by Mrs John Herschel [sic], 2nd edn (London, 1879; first publ. 1876; hereafter Memoir), contain a wealth of primary sources with commentary. The partnership of William and Caroline as seen through the eyes of Caroline is explored by the present writer in a work now in press entitled The Herschel partnership: As viewed by Caroline; references will be found therein to what follows.

Hamel Jürgen , “Ein Beitrag zur Familiengeschichte von Friedrich Wilhelm Herschel”, Gauss-Gesellschaft e. v. Göttingen Mitteilingen, no. 26 (1989), 99–103.

Chronicle, 2.

From the autobiography written by Caroline in the 1820s, i, 64 (original now in the Harry Ransom Library of the University of Texas at Austin; hereafter: 1820s autobiography).

From the autobiography written by Caroline in the early 1840s, i, 27–28 (fair copy now in the Harry Ransom Library of the University of Texas at Austin; hereafter: 1840s autobiography).

1840s autobiography, ii, 8.

Chronicle, 65.

1840s autobiography, ii, 14.

1820s autobiography, ii, 12.

1820s autobiography, ii, 6.

RAS MS W.5/12/1, 44. Reflectors needed duplicate primary mirrors because the metal tarnished while in use under the damp night sky. By having duplicate mirrors, the observer could use one in the telescope while the other was being repolished.

In the event, the public announcement of the dedication, whereby the planet was named Georgium Sidus, came (in the form of an open letter from William to Banks , Philosophical transactions, lxxiii (1783), 1–3) after the patronage was conferred.

Clerke , The Herschels (ref. 2), 121, cites Caroline as commenting that her “thoughts were anything but cheerful” on Whit-Sunday, 1782, when William performed and she sang in public for the last time. If this was indeed the case, she must have foreseen the end of her musical career.

Memoir, 52.

Historisches Museum, Hannover. See Bullard Margaret , “My small Newtonian sweeper — Where is it now?”, Notes and records of the Royal Society of London, xlii (1988), 139–48.

Pigott archives of the Royal Astronomical Society, Letter 60.

Memoir , 64–65; Chronicle, 153.

Chronicle, 153.

RAS MS C. 1/1.1, 38.

Cited in Chronicle, 169.

Chronicle, 174.

Chronicle, 174.

Chronicle, 173.

Memoir, 178.

RAS MS W.1/5.2(i).

Memoir, 209.

It must however be admitted that many of these sweeps were of sky between the zenith and the North Celestial Pole, directions in which it was awkward to manoeuvre the telescope. Also, William became involved in other observational programmes that proved time-consuming.

Letter from Lalande, RAS MS W.1/13.L.23, dated 1 April 1792. The prize(s) were “pour l'ouvrage le plus utile ou la decouverte la plus important pour les sciences ou les arts”.

RAS MS W.1/13.L.11,16 August 1788: “Je n'oublierai jamais surtout la nuit du 5 Aout, j'ai dit à tout le monde que jamias je n'en avois passé d'aussi agréables, sans excepter même celles d'amour.”.

RAS MS C. 1/1.4.

RAS MS C.1/1.2 91.

Chronicle, 246.

Memoir, 94–95.

RAS MS W.1/13.W.194, written summer of 1789.

Memoir, 92.

Chronicle, 251.

Memoir, 100.

Memoir, 109. She had written up a fair copy in a bound volume, which she entitled “A catalogue of the stars which have been observed by W^m Herschel in a series of sweeps; brought into zones of N[orth] P[olar] Distance and order of R[ight] A[scension] for the year 1800, by applying the variation given with each respective star in Wollaston's or Bode's Catalogues”, RAS MS C.3/2.3.

William was compiling a complete set of 72 papers. Eventually the set was auctioned by Sotheby's as Lot 393 of their Herschel sale of 4 March 1958; it fetched a mere £45.

Memoir, 130.

Memoir, 226.

RAS MS J.1/1.

Clerke , The Herschels (ref. 2), 132.

Cited in Clerke , The Herschels (ref. 2), 132. Biographers have assumed that Caroline carried out the entire undertaking in Hanover, and so their astonishment at what she achieved is easy to understand. Yet it would have been odd for Caroline to base herself on a catalogue that took 1790 as its epoch, and then calculate positions for 1800, rather than for 1825 when John was to start his work.

Memoir, 225. The gold medal is now in Girton College, Cambridge, and the volume in the Royal Society Library.

Memoir, 336.

Memoir, 52. The (sidereal) time when a star crosses the meridian yields one of its coordinates.

Schaffer Simon , ‘“The great laboratories of the universe’; William Herschel on matter theory and planetary life”, Journal for the history of astronomy, xi (1980), 81–111, pp. 96–100.

Chronicle, 369.