Euphemia Lofton Haynes was an American mathematician. She earned her degree @smithcollege in 1914, and her master's @UChicago in 1930. She became the first black US woman (and 9th black US person) to gain a PhD in mathematics in 1943, at @CatholicUniv. #STEMlegends #WomenInSTEM pic.twitter.com/pEHldXUxS2

— RAS Women in STEM (@RAS_Women) May 31, 2018

Haynes became a Professor of Mathematics at Miner Teachers College and was the first woman to chair the D.C. School Board, where she was active in abolishing laws that discriminated against women and people of colour in the USA. #STEMlegends #WomenInSTEM

— RAS Women in STEM (@RAS_Women) May 31, 2018

Agnes Mary Clerke was an Irish astronomer who wrote about astrophysics and the history of astronomy. She became an honorary member of @RoyalAstroSoc in 1903, along with Margaret Huggins, following Herschel, Somerville, and Sheepshanks. #STEMlegends #WomenInSTEM pic.twitter.com/7jVBCkUU9D

— RAS Women in STEM (@RAS_Women) May 30, 2018

Caterina Scarpellini was an Italian astronomer and meteorologist. She discovered a comet in 1854 and established a weather station in Rome in 1856. She was also an assistant at the Roman Campidoglio Observatory and a member of @georgofili in Florence. #STEMlegends #WomenInSTEM pic.twitter.com/TkDnElrhK2

— RAS Women in STEM (@RAS_Women) May 29, 2018

Elizabeth Brown was a British astronomer specialising in the Sun. She joined @LiverpoolAS but was refused membership of @RoyalAstroSoc in 1892 because she was a woman. She helped found @BritAstro a national body for amateur astronomers. #STEMlegends #WomenInSTEM pic.twitter.com/idWZMC4u7x

— RAS Women in STEM (@RAS_Women) May 28, 2018

Mary Anning was a fossil collector, illustrator, and palaeontologist from the UK. She discovered and identified many marine fossils from the Jurassic period in the cliffs at Lyme Regis, Dorset in the early 1800s. #STEMlegends #WomenInSTEM pic.twitter.com/AmrVn3XsKq

— RAS Women in STEM (@RAS_Women) May 27, 2018

Anning discovered and identified ichthyosaurs, ancient fish and crocodiles, ammonites, and sea lilies, as well as the first complete Plesiosaurus in 1823, and the first British flying reptiles known as pterosaurs in 1828. These were displayed at the British Museum. pic.twitter.com/mbjAYd570q

— RAS Women in STEM (@RAS_Women) May 27, 2018

Anning’s discoveries were the basis for Duria Antiquior, a more ancient Dorset. This is a watercolour depicting life in ancient Dorset painted by the English geologist Henry De la Beche in 1830. It was the first image of its kind depicting prehistoric life. pic.twitter.com/TCAhYi6GC0

— RAS Women in STEM (@RAS_Women) May 27, 2018

Alice Everett was a British astronomer and engineer. She was the first woman to be paid for astronomical work at @ROGAstronomers. She was nominated as a Fellow of @RoyalAstroSoc in 1892, along with Elizabeth Brown and Annie Russell Maunder. #STEMlegends #WomenInSTEM pic.twitter.com/4wyj20YG4l

— RAS Women in STEM (@RAS_Women) May 26, 2018

All three were refused Fellowship and one Fellow said:“it was practically a proposal to introduce into these dull meetings a social element, and all we shall require is a piano and a fiddle…and I am sure many of my young friends will be glad to dance through most of the papers.”

— RAS Women in STEM (@RAS_Women) May 26, 2018

Mary Ann Mantell was a British scientific illustrator who discovered the first fossils of Iguanodon in Sussex in 1822. This was the first type of dinosaur to be discovered, with the name Dinosauria coined in 1842. #STEMlegends #WomenInSTEM pic.twitter.com/GRnlwD07LR

— RAS Women in STEM (@RAS_Women) May 25, 2018

Isis Pogson was a British astronomer and meteorologist. She was the first woman to be nominated for election as a Fellow of @RoyalAstroSoc in 1886. This was deemed this illegal because the society's royal charter, from 1831, used the pronoun ‘he’. #STEMlegends #WomenInSTEM pic.twitter.com/F9WgwR8rPd

— RAS Women in STEM (@RAS_Women) May 24, 2018

Anna Volkova was a Russian chemist. She became the first woman to graduate as a chemist in 1870 and was the first to join the Russian Chemical Society. She led chemistry classes for female students with Dmitri Mendeleev, who developed the periodic table. #STEMlegends #WomenInSTEM pic.twitter.com/cW65aGnNsy

— RAS Women in STEM (@RAS_Women) May 23, 2018

Elizabeth Fulhame was a Scottish chemist and an honorary member of @PhilaACS. She published An Essay on Combustion in 1794. This is considered a precursor to work by Jons Jakob Berzelius, who is thought of as one of the founders of modern chemistry. #STEMlegends #WomenInSTEM pic.twitter.com/cwvyUYIsNW

— RAS Women in STEM (@RAS_Women) May 22, 2018

Etheldred Benett was an English geologist, instrumental in developing the field. Her fossil collection was considered one of the largest at the time, and her painting of the meteorite of 1813 and her sketches of fossil Alcyonia can be found at @geolsoc. #STEMlegends #WomenInSTEM pic.twitter.com/DisHb0QSoE

— RAS Women in STEM (@RAS_Women) May 21, 2018

Anne Sheepshanks was a British benefactor born in Leeds in 1794. She became an honorary member of @RoyalAstroSoc in 1862. She donated almost two hundred books to @astro_librarian, and funded the Sheepshanks telescope at Cambridge Observatory. #STEMlegends #WomenInSTEM pic.twitter.com/13OqgYxarm

— RAS Women in STEM (@RAS_Women) May 20, 2018

Sophie Germain was a French mathematician and one of the pioneers of elasticity theory. She also worked on number theory, providing a foundation for mathematicians working on Fermat's Last Theorem. #STEMlegends #WomenInSTEM pic.twitter.com/Ldn5r0cLRh

— RAS Women in STEM (@RAS_Women) May 19, 2018

Germain corresponded with fellow mathematicians Joseph Louis Lagrange, Adrien-Marie Legendre, and Carl Friedrich Gauss. She did not give her real name at first, so they wouldn't know she was a woman. When she disclosed her true identity in 1807, Gauss replied:

— RAS Women in STEM (@RAS_Women) May 19, 2018

"when a woman, because of...our customs and prejudices, encounters infinitely more obstacles than men in familiarising herself with [number theory's] knotty problems…”

— RAS Women in STEM (@RAS_Women) May 19, 2018

“…yet overcomes these fetters and penetrates that which is most hidden, she doubtless has the most noble courage, extraordinary talent, and superior genius".

— RAS Women in STEM (@RAS_Women) May 19, 2018

Elizabeth Philpot was a palaeontologist and fossil collector from Dorset, UK. She collected fossils with her sisters Mary and Margaret in c 1800. She collaborated with Mary Anning and Mary and William Buckland, who was president of @geolsoc. #STEMlegends #WomenInSTEM pic.twitter.com/uSuYgaLE04

— RAS Women in STEM (@RAS_Women) May 18, 2018

Mary Somerville was a British astronomer. She was one of the first women to become an honorary member of @RoyalAstroSoc in 1835, along with Caroline Herschel. She translated mathematician Pierre-Simon Laplace's The Mechanism of the Heavens into English. #STEMlegends #WomenInSTEM pic.twitter.com/xRjGiBSa6K

— RAS Women in STEM (@RAS_Women) May 17, 2018

Somerville went on to publish three books of her own. These directly influenced natural philosopher James Clerk Maxwell, and astronomer John Couch Adams, who predicated the location of the planet Neptune due to a discussion in her first book. #STEMlegends #WomenInSTEM

— RAS Women in STEM (@RAS_Women) May 17, 2018

Huang Lü was a Chinese astronomer and mathematician. She is known as the first woman in China to work with optics and photographic images. She created a type of telescope, an early camera, and type of thermometer in c 1790. #STEMlegends #WomenInSTEM pic.twitter.com/qRnbKgDjCk

— RAS Women in STEM (@RAS_Women) May 16, 2018

Caroline Herschel was a German astronomer. She discovered a new galaxy, an asteroid, and five comets. She also compiled star and nebula catalogues. She was an honorary member of @RIAdawson and was presented with a Gold Medal from the King of Prussia. #STEMlegends #WomenInSTEM pic.twitter.com/SWzgjrLCmH

— RAS Women in STEM (@RAS_Women) May 15, 2018

Herschel was presented with a Gold Medal from @RoyalAstroSoc in 1828. No other woman would be presented with this award until 1996, with Vera Rubin. Herschel was also one of the first women to be named an honorary member of @RoyalAstroSoc, along with Mary Somerville in 1835.

— RAS Women in STEM (@RAS_Women) May 15, 2018

Marie-Jeanne de Lalande was a French astronomer who created a catalogue of 10,000 stars in 1799. Mathematician Carl Friedrich Gauss described her as the only French woman that worked in science in 1806, a year before Sophie Germain revealed her gender. #STEMlegends #WomenInSTEM pic.twitter.com/Hn30yHd76q

— RAS Women in STEM (@RAS_Women) May 14, 2018

Nicole-Reine Lepaute was a French astronomer. She helped construct an astronomical clock that was approved in 1753. She calculated the timing of a solar eclipse, compiled a number of star catalogues, and helped predict the return of Halley's Comet. #STEMlegends #WomenInSTEM pic.twitter.com/yK6SKaMhZN

— RAS Women in STEM (@RAS_Women) May 13, 2018

Louise du Pierry was a French astronomer and a member of the Academy of Sciences of Béziers. She became the first female professor at @Sorbonne_U in Paris in 1789, teaching female students. She predicted eclipses and computed latitude tables. #STEMlegends #WomenInSTEM pic.twitter.com/3VGgmifFIA

— RAS Women in STEM (@RAS_Women) May 12, 2018

Jacoba van den Brande was a Dutch natural philosopher. She founded the first all-female science academy in the world in 1785. This was the Physics/Natural History Society of Women in Middelburg. She became the first director. #STEMlegends #WomenInSTEM pic.twitter.com/pyUsVQmRpc

— RAS Women in STEM (@RAS_Women) May 11, 2018

Maria Gaetana Agnesi was an Italian mathematician. She is known for writing the first book that discussed differential and integral calculus. The French Academy of Sciences stated that this was "the most complete and best made treatise [on mathematics]". #STEMlegends #WomenInSTEM pic.twitter.com/NfjBPnm4JJ

— RAS Women in STEM (@RAS_Women) May 10, 2018

Pope Benedict XIV appointed Agnesi Professor of Mathematics at the University of Bologna in 1750. She now has a crater on Venus named after her. #STEMlegends #WomenInSTEM

— RAS Women in STEM (@RAS_Women) May 10, 2018

Émilie du Châtelet was a French mathematician and natural philosopher. She was the first to suggest that infrared radiation might exist, and improved on Newtonian mechanics, deriving a proof for the conservation of energy. #STEMlegends #WomenInSTEM pic.twitter.com/j3OFV3MfPq

— RAS Women in STEM (@RAS_Women) May 9, 2018

In 1740, du Châtelet combined the theories of mathematicians Gottfried Leibniz and Willem 's Gravesande to show that the energy of a moving object is proportional to the square of its velocity. This is an early form of the equation for kinetic energy. #STEMlegends #WomenInSTEM

— RAS Women in STEM (@RAS_Women) May 9, 2018

Du Châtelet argued that women should be allowed to be educated to the same level as men, and that by denying women an education, society was preventing them from partaking in the arts and sciences. #STEMlegends #WomenInSTEM

— RAS Women in STEM (@RAS_Women) May 9, 2018

Cristina Roccati was an Italian natural philosopher. She became the third woman to gain an academic qualification in Italy in 1751, with a degree from University of Bologna. She studied astronomy at @UniPadova and taught at the Accademia Dei Concordi. #STEMlegends #WomenInSTEM pic.twitter.com/RgLcwqMG7i

— RAS Women in STEM (@RAS_Women) May 8, 2018

Petronella Johanna de Timmerman was a Dutch natural philosopher and mathematician. She conducted scientific experiments with Johann Hennert and intended to write a book about physics for women, which she was unable to complete before her death in 1786. #STEMlegends #WomenInSTEM pic.twitter.com/V1Bh7Qi0F4

— RAS Women in STEM (@RAS_Women) May 7, 2018

Faustina Pignatelli was an Italian mathematician. She became the second woman elected to the Academy of Sciences of the Institute of Bologna in 1732, after Laura Bassi. She published the Problemata Mathematica in 1734. #STEMlegends #WomenInSTEM pic.twitter.com/p4zC7xCZ2T

— RAS Women in STEM (@RAS_Women) May 6, 2018

Wang Zhenyi was a Chinese astronomer and mathematician from the Qing dynasty, who breached custom in c 1790 by pursuing higher education. Zhenyi explained and calculated equinoxes and eclipses and campaigned for equality between men and women. #STEMlegends #WomenInSTEM pic.twitter.com/6nreRIEZ7D

— RAS Women in STEM (@RAS_Women) May 5, 2018

Mary Buckland was a British palaeontologist born in 1797. She collected fossils and worked as a curator at @morethanadodo. She also contributed to a book showing that the biblical flood was not supported by geology. #STEMlegends #WomenInSTEM #FossilFriday pic.twitter.com/GqxkPD96yh

— RAS Women in STEM (@RAS_Women) May 4, 2018

Laura Bassi was an Italian natural philosopher. She became the second woman to receive a PhD in the world in 1732, and was the first female Professor in Europe. She helped introduce Newtonian mechanics to Italy and was chosen to advise Pope Benedict XIV. #STEMlegends #WomenInSTEM pic.twitter.com/a8qLl8LQO3

— RAS Women in STEM (@RAS_Women) May 3, 2018

María Andrea Casamayor was a Spanish mathematician born in Zaragoza in 1700. She published two popular textbooks on mathematics including El parasisolo and Tirocinio aritmetico, published using a male pseudonym in 1738. #STEMlegends #WomenInSTEM pic.twitter.com/Hdhf4JjAfB

— RAS Women in STEM (@RAS_Women) May 2, 2018

Celia Grillo Borromeo was an Italian mathematician and scholar who knew 8 languages and specialised in geometry. She is best known for discovering the Clelia curve in 1728. This gives the formula for the curves that could be drawn on a rotating sphere. #STEMlegends #WomenInSTEM pic.twitter.com/qXxs3k0KIp

— RAS Women in STEM (@RAS_Women) May 1, 2018