Date context
1738–1822
From music to telescopes
Born in Hanover, Herschel earned his living in Britain through musical teaching, performance and composition. An interest in mathematics and optics led him to grind mirrors and build reflecting telescopes. His sister Caroline later joined the observing and record-keeping work.
Recognizing Uranus
In March 1781 Herschel observed a moving object unlike an ordinary star and initially reported a possible comet. Further observations and orbital calculations established it as a planet. Finding the object, identifying its nature and determining its orbit were separate stages.
References: [1]
Beyond visible red light
In 1800 he dispersed sunlight with a prism and used thermometers to compare heating across the spectrum. Heating persisted beyond the visible red end. The experiment revealed radiation invisible to the eye, subsequently known as infrared radiation.
Building catalogues together
Herschel systematically observed double stars, nebulae and star clusters. Caroline’s recording and later catalogue work formed an essential part of this sustained programme. William, Caroline and the next generation’s John Herschel made distinct contributions that should not be conflated.