Family of British astronomers.
The German-born William Herschel (17381822) immigrated to England in 1757 and initially supported himself through music. In order to study distant celestial objects, he ground his own mirrors, producing the best telescopes of the day. His discovery of Uranus catapulted him to fame at age 43. He hypothesized that nebulae (those objects now known to be galaxies ) are composed of stars and developed a theory of stellar evolution. He also discovered infrared radiation . He was knighted in 1816. His sister, Caroline Lucretia Herschel (17501848), contributed to her brother's researches, carrying out many of the necessary calculations. She also detected by telescope three nebulae and eight comet s. In 1787 the king gave her an annual pension in recognition of her work. She continued to work for decades after William's death. William's son John (17921871) studied mathematics at the University of Cambridge and from 1816 assisted his father. He later undertook a journey to the Southern Hemisphere to survey its skies; he returned in 1838, having recorded the locations of 68,948 stars. Also an accomplished chemist, he invented (independently of William Henry Fox Talbot ) the process of photography on sensitized paper. He was knighted in 1831. His sons Alexander Stewart (18361907) and John (18371921) also became astronomers.