John Evershed


John Evershed CIE FRS FRAS was an English astronomer. He was the first to observe radial motions in sunspots, a phenomenon now known as the Evershed effect.

Biography

Evershed was born in Gomshall, Surrey to John and Sophia Evershed. He made the discovery which bears his name while at Kodaikanal Observatory in 1909. After retirement in 1923 he set up a private observatory at Ewhurst, Surrey and built a large spectroheliograph of special design and another with high-dispersion liquid prism. He continued to study the wave-lengths of H and K lines in prominences, giving values of the solar rotation at high levels in different latitudes and at different phases of the solar cycle. Work continued until 1950 when the observatory closed and he presented some of his instruments to the Royal Greenwich Observatory at Herstmonceux. In the autumn of 1890 was a founding member of the British Astronomical Association. He directed its Solar Spectroscopy Section and Spectroscopic Section.

Awards and honours

In 1894 Evershed was elected a Fellow of the Royal Astronomical Society, in 1918 he was awarded the Gold Medal of the Royal Astronomical Society. He was elected a Fellow of the Royal Society in May, 1915. The Evershed crater on the Moon is named in his honor. He was awarded as a Companion of the Indian Empire on his retirement in 1923.

Personal life

Evershed was married to fellow astronomer Mary Acworth Orr Evershed, with whom he co-authored some work. He died in Ewhurst, Surrey on 17 November 1956.
He also had interest in lepidoptera and other insects. W. H. Evans described a butterfly and named it after Evershed as the first specimen was collected by Evershed. In 2015 his archive was acquired by the Science Museum, London.