Helen Megaw

Helen Dick Megaw (1 June 1907 – 26 February 2002) was an Irish crystallographer who was a pioneer in X-ray crystallography. She made measurements of the cell dimensions of ice and established the Perovskite crystal structure.

Education and career Megaw was born in Dublin to mathematics teacher Annie McElderry (1874-1968) and judge Robert Megaw, two graduates of Queen's University Belfast who were both originally from Ballymoney, Antrim. She was educated at first at Alexandra College in Dublin, and then briefly at Methodist College in Belfast after the family (including younger brother John, later a leading judge) moved back there in 1921, and finally at the Roedean School in England. While still at school, Megaw read Bragg's X-rays and Crystal Structure. She spent a year at Queen's University, Belfast and Girton awarded her a Hertha Ayrton research scholarship which she used to study in Vienna in 1934-1935 under Hermann Francis Mark. In 1935 Megaw co-published with Bernal an influential method for fixing the position of hydrogen atoms known as the Bernal-Megaw model. In 2019, some of Megaw's fabric samples were displayed at the Science Museum, London as part of an exhibition "The Art of Innovation" which explored the relationship between art and science.

Legacy and honors In recognition of her work in determining the structures of ice crystals, Megaw Island in the Southern Ocean is named for her. Megawite (CaSnO3), a perovskite-group mineral, is also named after her.

In 1976, Megaw gave a collection of fabric samples from the Festival of Britain along with a souvenir guide-book to the Science Museum in London.

In 1989, Megaw became the first woman to receive the Roebling Medal of the Mineralogical Society of America. She had honorary doctorates from the Universities of Cambridge and Queen's University Belfast.