A photograph of the Sun, from a booklet by John Titterton entitled 'Autographs of the Sun', taken with the Heliautograph of Reverend William Selwyn of Ely, in 1862. This series of photographs draws particular attention to the sunspots that photographers attempted to record with great interest. Sunspots are regions of unusually high magnetic field in the photosphere. Cooler than the surrounding areas, they look darker, appearing and disappearing periodically. Research into the sunspots was carried out between 1853 and 1861 by astronomer Richard Christopher Carrington [1826-1875]. This prompted calls for photographers to assist in recording details. Sir John Herschel asked photographers to make daily records of the sun's appearance, in particular the variation of these spots.
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