Astronomical discoveries of the Herschel family

The Royal Society

Discover a dynasty of scientists who contributed uniquely to astronomy, from making telescopes to charting the Milky Way. 

Structure of the galaxy
William Herschel FRS (1738-1822) and his sister Caroline Herschel (1750-1848) made large scale maps of stars and nebulae, allowing William to develop theories on the structure of our galaxy. In 1781, Sir William realised he had accidentally discovered a planet – Uranus – and later observed moons orbiting the new world.

William Herschel was the first to use discover an entirely new planet using a telescope, Uranus, 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.

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.

William Herchel 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. 

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.

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.

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 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 continued the work of his father William and aunt Caroline. John was instrumental in furthering the Royal Astronomical Society and served three times as its President. A polymath, John is most famous today for his contribution to photographic processes and received the Royal Society'a Copley Medal in recognition of his mathematical studies.

John Herschel continued to sweep for nebulae. The faint objects, many of them galaxies, 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.

This photograph of what appears to be a crater on the Moon, was taken by John Herschel. In fact it is of a papier-maché model of the moon as photography and telescopy had not been joined yet.

The Herschel's scientific legacy was carried out 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) who contributed various astronomical observations. Colonel 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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