Maskelyne, Nevil

English astronomer. He made observations to investigate the reliability of the lunar distance method for determining longitude at sea. In 1774 he estimated the mass of the Earth by noting the deflection of a plumb line near Mount Schiehallion in Perthshire, Scotland.

Maskelyne was appointed Astronomer Royal in 1765 and held that office until his death. He began publication in 1766 of the Nautical Almanac. This contained astronomical tables and navigational aids, and was probably his most enduring contribution to astronomy.