Henriette Leavitt was an astronomer who worked on special types of stars called Cepheid Variables. As a female astronomer in the early 1900s, she faced many obstacles in her research. Nonetheless, her work became the basis for that of many future astronomers.
Henrietta Leavitt found the Cepheid Variable Period-Luminosity Relationship. This is one of many other large impacts she made to the field of astronomy.
Leavitt’s Early Life
Henrietta Leavitt was born in Cambridge, Massachusetts. Her father was a Congregational minister. She later went to Oberlin College and the Society for Collegiate Instruction of Women. This later became Radcliffe College.
During her last year of school, in 1892, Leavitt found astronomy. After she left school, she decided to take another course in it. But, she didn’t get to. She suffered a serious illness and had to spend several years at home. The illness left her very deaf.
Despite all of this, Leavitt did not forget about her passion for astronomy. She began to volunteer at the Harvard College Observatory in 1895. Seven years later, director Charles Pickering gave her a place on the full time staff.
She only made a salary of 30 cents an hour and had few chances to do theoretical work. But, she did become the head of the Photographic Photometry department. There she studied photo images of stars to figure out their size.
What Did Leavitt Discover?
During her career, Leavitt found more than 2,400 variable stars. That’s about half of the total stars they knew of during that time! These stars alternate from bright, to dim, and back regularly.
The Cepheid Variable Period-Luminosity Relationship
Leavitt’s work led to her most important contribution to the field of astronomy. This is the Cepheid Variable Period-Luminosity Relationship. Wow, try saying that five times fast!
Leavitt intensely observed the Cepheids, a certain class of variable star. Leavitt discovered a direct correlation between the time it takes a star to go from bright, to dim, and back again to bright. This knowledge helped other astronomers to make their own groundbreaking discoveries. A great example of this is Edwin Hubble’s work.
The famous astronomer Edwin Hubble. Much of his work wouldn’t have been possible with Leavitt’s findings!
The Harvard Standard
This was not Leavitt’s only achievement. She developed a standard of photographic measurements. In 1913, the International Committee on Photographic Magnitudes accepted her standard. It was then named the “Harvard Standard”.
This standard was created using 299 plates from 13 telescopes. She then used logarithmic equations to order stars over 17 magnitudes of brightness. Throughout her life, Leavitt continued working on this to refine and enlarge the topic.
The End of Leavitt’s Time
Due to the prejudices of that era, Leavitt was not allowed to pursue her own topics of study. Instead, she had to research what the head of the observatory assigned. Although she was unable to use her intellect to the fullest, a colleague remembers her as “possessing the best mind at the Observatory.”
She worked at the Harvard College Observatory until her death from cancer in 1921. But, her determination and strength in discovery are still remembered to this day. A modern astronomer calls her “the most brilliant woman at Harvard.”
For more information on Henrietta Swan Leavitt, watch this video: