Herbert Hall Turner (13 August 1861, Leeds – 20 August 1930, Stockholm) was a British astronomer and seismologist.
Herbert Hall Turner was educated at Clifton College and Trinity College, Cambridge. In 1884 he accepted the post of Chief Assistant at Greenwich Observatory and stayed there for nine years. In 1893 he became Savilian Professor of Astronomy and Director of the Observatory at Oxford University, a post he held for 37 years until his sudden death in 1930.
He was one of the observers in the Eclipse Expeditions of 1886 and 1887. In seismology, he is credited with the discovery of deep focus earthquakes. He is also credited with coining the word parsec, an astronomical unit of distance equal to the range at which the semiannual change in parallax of a celestial object is equal to one second of arc (equal to 3.26 light-years.)
His 1897 Royal Society candidature citation read: " Secretary of the Royal Astronomical Society. Was Chief Assistant at the Royal Observatory, Greenwich 1884-1894. Author of various papers among which may be mentioned:"
- On the correction of the Equilibrium theory of tides for the continents (with G H Darwin, Proc.RS. vol lx)
- Report of observations of total solar eclipse of Aug 29 1886 (Phil Trans. vol 180A),
- On Mr Edgeworth's method of reducing observations relating to several quantities (Phil. Mag. Vol24).
- On Mr Leath's Intersects (Monthly Notices R.A.S. vol xlvi).
- On observations for coincidence of collimators at Royal Observatory Greenwich (M,N. Vols xlv and liii).
- On the variations of level against of the Transit Circle at Royal Observatory Greenwich (M.N. Vol.xlvii).
- On the longitude of Paris (M.N. vol li).
- On stellar Photography (M.N. Vols xlix and liv)
- On the R-D discordnace (M.N. vol Liii p. 374 and 424, vol Liv p. 486, Mem Part. 3. vol ii);
- On new forms of levels (M.N. Vol Lii).
- Conference of the Cape (1880) and Greenwich (1880) Star Catalogues (Mem. Rs.F.S, vol Li).
- On the reduction of measures of photographic plates (N.N. vol LiV)
He died of a brain haemorrhage in 1930 at a conference in Stockholm. He had married Agnes Margaret Whyte in 1899; they had one daughter, Dr Ruth Turner of St Mary's Hospital, London.
A few months before Turner's death in 1930, the Lowell Observatory announced the discovery of a new minor planet, and an eleven-year-old Oxford schoolgirl, Venetia Burney, proposed the name Pluto for it to her grandfather Falconer Madan, who was retired from the Bodleian Library. Madan passed the name to Turner, who cabled it to colleagues at the Lowell Observatory in the United States. The new minor planet was officially named "Pluto" on 24 March 1930.