Structure of the galaxy
William Herschel FRS (1738-1822) and his sister Caroline Herschel (1750-1848) catalogued stars and nebulae, allowing William to develop theories on the structure of our galaxy. In 1781, William realised he had accidentally discovered a planet – Uranus – and later observed moons orbiting the new world.
Account of a Comet (1781) by William Herschel (1738-1822)The Royal Society
William Herschel was the first to discover an entirely new planet using a telescope. Uranus, first named Georgium Sidus in honour of King George III, was first spotted on 13 March 1781.
As you can discover in this letter to the Royal Society, he initially believed that the object was a comet but further evidence convinced him that this must be a planetary body. The discovery was truly sensational and made Herschel internationally famous.
Portrait of William Herschel (1781) by Louise du Piery (1746-1807)The Royal Society
This profile portrait of William Herschel FRS was engraved after an original drawing by Louise du Piery (1746-1807).
Du Piery was an astronomer in her own right, a pupil of the holder of the chair of astronomy at the College de France Jérôme Lalande (1732-1807) and the first female Professor of the Sorbonne, teaching astronomy to female pupils.
The engraving clearly acknowledges 'Mme Dupiery' as the original artist in the bottom left corner.
In the portrait, Herschel’s new planet is shown in the upper left of the image, beyond the orbit of Saturn.
Portrait of Sir William Herschel (1912) by Anonymous and after William Artaud (1763-1823)The Royal Society
William Herschel was instrumental in establishing an astronomical society in Britain. The Royal Astronomical Society was founded in 1820 and received its Royal Charter in 1831. William served shortly as first President of the society before his death in 1822.
The science of observation
Caroline Lucretia Herschel is renowned for her discovery of eight comets and for a lifetime of observation in partnership with her brother William. This portrait was owned by Caroline’s nephew and pupil, John Frederick William Herschel (1792-1871) and engraved for the Royal Society.
Letter to Charles Blagden announcing the discovery of a comet Letter to Charles Blagden announcing the discovery of a comet (1786-08-01) by Caroline Lucretia Herschel (1750-1848)The Royal Society
In this letter to the Royal Society’s Secretary, Charles Blagden (1748-1820), Caroline announces the discovery of a comet first observed on 1 August 1786.
Nebulae sweep books (1783/1802) by Caroline Lucretia Herschel (1750-1848) and William Herschel (1738-1822)The Royal Society
The Herschels used a 20-foot 18-inch aperture telescope to create deep-sky surveys in order to record the tenuous objects generally referred to as ‘nebulae’. Caroline meticulously catalogued the outcomes of the sweeps.
Title-page of the 'Catalogue of Double Stars' (1782) by William Herschel (1738-1822)The Royal Society
Using the large telescope enabled William to observe stellar objects which had never been recorded before. He published his discoveries in 'catalogues' of stars in the journal of the Royal Society, describing 269 double stars in this 1782 publication.
LIFE Photo Collection
This popularised depiction of Herschel's discovery of Uranus represents Caroline taking notes while William is observing.
William constructed the first ever 40-foot telescope in Slough, at what is known as Observatory House, to support his observations. The telescope remained largest in the world for half a century.
The identification of the planet took several observations and analyses and did not happen in a single night...
...what is true however, is that Caroline describes having little time behind the telescope when her brother is present.
A scientific dynasty
Sir John Herschel furthered the work of his father William and aunt Caroline. John continued his family's association with the Royal Astronomical Society and served three times as its President. A polymath, John is famous today not only for astronomy, but also for his contribution to photographic processes. He received the Royal Society Copley Medal in recognition of his mathematical studies.
Meteorological Observations at the Cape of Good Hope (1836/1837) by John Frederick William Herschel (1792-1871)The Royal Society
John Herschel travelled to the Cape of Good Hope, in South Africa to extend his father's observations to the Southern Hemisphere. These are his manuscript observations for 1836.
Drawings of nebulae (1833) by John Frederick William Herschel (1792-1871)The Royal Society
John Herschel continued to sweep for nebulae. The faint objects, many of them galaxies, others gas clouds, meant that he drew at the limit of the human eye, sketching in dark environments. The difficulty would later be resolved by linking photography to telescopes.
List of stars from 'On the parallax of the fixed stars' (1826) by John Frederick William Herschel (1792-1871)The Royal Society
An excellent mathematician, John Herschel also proposed a new method to investigate stellar parallax, that is the apparent shift of stars due to the Earth's orbital path a key phenomenon then not yet observable by telescopes.
Sir John Frederick William Herschel (1867) by Julia Margaret CameronThe Museum of Fine Arts, Houston
The Herschels' scientific legacy was carried on by several of John's children.
For instance, Alexander Stewart Herschel FRS (1836-1907) identified comets as the source of meteor showers and Colonel John Herschel FRS (1837-1921) gathered information on planet Earth using pendulum observations. John Herschel donated his father's correspondence to the Royal Society.
Come to our archives to discover more on this extraordinary scientific dynasty.
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