Kathleen Lonsdale was born in 1903 in Newbridge, Ireland. Today she is remembered for using X-rays to discover the shapes of molecules.
Lonsdale was careful. She measured X-ray patterns by hand for months to be sure her results were right.
In 1929, Lonsdale used X-rays to prove that the benzene ring is flat. In 1945, Lonsdale became one of the first two women elected Fellows of the Royal Society.
In 1949, Lonsdale became a professor at University College London. (Crystal: a solid whose tiny particles are arranged in a repeating pattern.)
Lonsdale died in 1971. Lonsdaleite, a rare form of diamond, is named after her.