February 11th marks the United Nations Day of Women and Girls in Science. This post features just some of my personal favourite female pioneers that contributed towards the advancement of space science and space exploration.
Wang Zhenyi (1768–1797) of the Chinese Qing dynasty, defied societal norms and educated herself in astronomy and mathematics. Known for her works in writing and poetry, she is also recognised for proving in simple terms how equinoxes move and how to effectively calculate their movement. Although she only lived to be 29, her personal experiments of the lunar and solar eclpises are considered to be very accurate and heavily influential for astronomy research at the time.
Annie Jump Cannon (1863-1941) was a female astronomer best known for creating and developing the current system by which scientists classify stars that is still used today. Her system ranks star types as O (hottest), B, A, F, G, K or M (coolest) and is known as the Harvard Classification Scheme.
Cecilia Payne-Gaposchkin (1900-1979) first proposed that the stars were composed primarily of hydrogen and helium in her doctoral thesis in 1925, as the first person to earn a PhD in astronomy from Radcliffe College (now part of Harvard University). She accurately connected the electromagnetic radiation characteristics of stars to their temperature and was able to predict that hydrogen was the overwhelming component of stars, making it the most abundant element in the Universe. This revolutionary work was initially rejected, as it contradicted the scientific understanding of the time, however her work was eventually proven to be correct.
Katherine Johnson's (1918-) mathematical contributions to orbital mechanics, a domain that solves the problems concerning the motion of rockets and spacecraft, was imperative to the success of the first American manned spaceflight missions. Johnson was one of several African-American women tasked with conducting the needed computing efforts to achieve NASA’s first accomplishments in human spaceflight. Johnson successfully determined the trajectory for the 1961 space flight of the first American in space, Alan Shepard. Upon the introduction of electronic computers, figures were checked by Johnson for accuracy. She later helped to calculate the proper spacecraft trajectory for the 1969 Apollo 11 flight to the Moon, as well as other calculations for the Space Shuttle program. In 2015, President Barack Obama presented Johnson with the Presidential Medal of Freedom and in 2016, NASA announced the naming of a building in her honor: the Katherine G. Johnson Computational Research Facility (at NASA's Langley Research Center). Katherine Johnson is the focus on the 2016 film Hidden Figures.
Vera Rubin (1928-2016) transformed modern physics and astronomy with her observations that effectively demonstrated the effects of gravity on stars and galaxies and provided important observational evidence for the existence of dark matter throughout the universe. Through her research, Vera found that the stars on the borders of galaxies were not slowing down as expected. Instead, their speed was increasing, which indicated that there must be another mass or force present to explain their movement. Furthermore, her research discovered that spiral galaxies are rotating so quickly that they should fly apart – a mystery became known as the galaxy rotation problem. Again, it was suggested that a large amount of unseen mass must be holding these galaxies together, which is now recognized as dark matter – a special type of matter that is believed to account for roughly 85% of the total matter in the universe. Rubin's findings were originally met with skepticism, but have since been confirmed over subsequent decades
Judith Love Cohen (1933-2016) worked as an electrical engineer on a specific component of the Apollo Program. The abort guidance system was developed to assist in direction and control in the event of an emergency. During the historic Apollo 13 mission, an explosion rendered much of the spacecraft inoperable (including its guidance system). The abort guidance system was used to bring the astronaut crew back to Earth safely. Judith also contributed to NASA’s Hubble Space Telescope and Tracking and Data Relay Satellite System programs.
Margaret Hamilton (1936-) served as the team lead of the MIT Instrumentation Laboratory that developed the software for the Apollo moon program. In fact, she is credited for coining the term “software engineering”. Shortly before touchdown on the moon during the Apollo 11 mission, the spacecraft’s computer set off an alarm that indicates that its systems were being tasked with processing power it could not undertake. Fortunately, Hamilton programmed the system to prioritize its tasks according to importance, prompting the astronauts onboard to respond to a go/no-go decision to land on the moon. Shortly thereafter, Neil Armstrong and Buzz Aldrin became the first humans to walk on the moon. Margaret continued her work in software engineering, including leading the software development for NASA’s Skylab space station. She then became the founder and CEO of Hamilton Technologies, which is responsible for creating the modelling language known as “Universal Systems Language” that has since provided system engineers and software developers with an innovative language that they can use to solve problems.In 2016, she was awarded the Presidential Medal of Freedom by American President Barack Obama.
Margaret Hamilton in 1969, standing next to listings of the software she and her MIT team produced for the Apollo project.
Valentina Tereshkova (1937-) became the first woman to go into space in 1963. She applied to the Soviet Union's space program and was accepted despite her lack of piloting experience due to her strong background in parachuting. During her 3-day flight onboard the Vostok 6, she orbited the Earth early 50 times. This flight nearly ended in disaster however (a fact that remained classified for roughly 40 years) when an error in the spacecraft's automatic navigation software caused the spacecraft to move away from Earth. This was quickly detected by Tereshkova and her team, who developed a new algorithm to allow for her safe landing. Velentina never flew to space again, but was regarded as a Soviet hero and remains active in the space community today.
Valentina Tereshkova in 1937. Credit: NASA