The most popular conundrum in cosmology, dark matter, has several names attached to its discovery.
One of them was Vera Florence Cooper Rubin commonly called Vera Rubin, whose role was one of the most crucial ones if not the most.
When Rubin started her master’s thesis, she never intended to find any evidence for dark matter.
What truly captivated her was galaxies, their dynamics in particular, and how that led to her bringing dark matter back into the limelight is one of the things we’ll be finding out in this article.
Vera Rubin’s Early Life and Education
Vera Rubin was born on July 23, 1928, in Philadelphia in the state of Pennsylvania, USA, as the second daughter to her parents who worked for the Bell Telephone company.
Her father, Pesach Kobchefski (Philip Cooper), was a mathematically talented electrical engineer while her mother was an exceptional temple choir singer.
Rubin’s passion for astronomy started when she first moved to Washington D.C. when she was 10.[1]
Every night, she used to watch the sky from the window in her room which was lined right next to her bed.
What fascinated me was that if I opened my eyes during the night, they had all rotated around the pole.
Vera Florence Cooper Rubin
She even built a telescope and all her essays in her English class were about Astronomy, she used every opportunity to delve deeper into the Universe.
Vera Rubin received her Bachelor’s degree in Astronomy from Vassar College in 1948, where she was the only woman to graduate.
She earned her master’s degree from Cornell University in 1951 and immediately enrolled in a doctoral program at Georgetown University.
Her Ph.D. dissertation on Fluctuations in the Space Distribution of Galaxies was completed in 1954 and concluded that galaxies indeed clumped together rather than being randomly distributed throughout the universe.
Difficulties Vera Rubin Faced During Her Career
Vera Rubin faced several challenges and difficulties as a woman pursuing a career in Astronomy and Astrophysics, particularly during the earlier years of her career when gender disparities in the field were more pronounced.
At the beginning of her academic journey in the 1940s, there were fewer opportunities for women in science, and many institutions had strict gender-based admissions and employment policies.
During her Masters, when she defended her thesis, one of her advisors, William Shaw, called her work sloppy.
However, he went on to suggest that she should consider presenting it at the American Astronomical Society (AAS) meeting.
Considering her circumstances – being pregnant with her first child, with the due date just a month before the meeting, and not being a member of the society – he kindly offered to deliver a presentation on her findings on her behalf.
However, this would’ve been in his name and not hers; so Rubin told Shaw that it wouldn’t be a problem if she were to go and present her work herself.
Unfortunately, her paper sparked a somewhat heated discussion, the comments she received were predominantly negative in nature and her paper was never published.
Some observatories and research institutions had restricted access for women, making it difficult for Rubin to access the equipment and facilities necessary for her research.
Vera Rubin did not receive a Nobel Prize during her lifetime, despite her significant contributions to the field of astrophysics, particularly her pioneering work on dark matter.
Historically, women in science have faced gender bias and discrimination, which may have influenced the recognition of their work.
Although there have been efforts to address gender disparities in recent years, Rubin conducted much of her groundbreaking research at a time when such biases were more pronounced.
Career and Contributions of Vera Rubin
After getting her Ph.D. Rubin went on to be an Instructor of Mathematics and Physics at Montgomery College.
From 1955 to 1965, she held several positions at Georgetown University, first as a research associate Astronomer, followed by being a lecturer, and finally, as an Assistant Professor of Astronomy.
In 1965, she joined the Carnegie Institute of Science (then, Carnegie Institution of Washington) as a staff member in the Department of Terrestrial Magnetism.[2]
At this point, she met Kent Ford and went on to work with him on quasars and later galaxy rotation curves.
Her paper about the anomaly observed in galaxy rotation curves prompted a theory of non-Newtonian gravity on galactic scales known as Modified Newtonian Dynamics (MOND) which still hasn’t been widely accepted by researchers.
As we know by now, Vera Rubin had an avid interest in galaxies, she also worked on the phenomenon of counter-rotation in galaxies.
She discovered that some gas and stars moved in the opposite direction to the rotation of the rest of the galaxy.
This challenged the prevailing theory that all of the material in a galaxy moved in the same direction and provided the first evidence for galaxy mergers and the process by which galaxies initially formed.
Galaxy Rotation Problem – Vera Rubin’s Discovery of Dark Matter
During her time as a graduate student at Cornell, Rubin got interested in galaxy dynamics due to Martha Stahr Carpenter who was obsessed with how galaxies and how their innards moved.[3].
Whilst pondering over what her master’s thesis should be about, she came across an article by George Gamow where he wondered, “What if we took the way solar systems rotate and applied it to how galaxies move in the universe?”
Thus, her quest to find out if galaxies move randomly or rotate around a pole began.
Through her observations, she noticed a plane that was denser with galaxies than other regions (later identified as a supergalactic plane).
Accordion: The Supergalactic plane is the dominant plane of the greatest concentration of nearby galaxy clusters in the sky, which passes through the Virgo cluster.
During her Ph.D. program at Georgetown University, she discovered that galaxies did indeed cluster together and it wasn’t random as we made them out to be.
In 1965, she met Kent Ford and his spectrometer, which was more sensitive as compared to its counterparts at the time at Carnegie Institution.
What’s a Spectrometer?
A spectrometer divides light into its constituent wavelengths; this helps us see how much blue or yellow or whichever color it’s made of, it consists of.
With this, they decided to observe quasars but quickly moved on to the Andromeda Galaxy since the competition was very high in the field of quasars which was recently discovered at the time.
Also, Rubin was way more interested in how galaxy rotations worked, no one had ever made a detailed study of it ever before.
What they expected to find, based on luminosity(meaning, luminous mass was clustered at the center), was for objects near the center to move faster than the objects near the edges since mass gives rise to gravity.
Instead, they observed that the rotational velocity of spiral galaxies either remains constant with an increase in the distance from the center or slightly rises, making the rotation curve flat.
Meaning that luminosity was not a sure factor for mass, this meant that some non-luminous mass existed that balanced out the lack of luminous mass at the edge of the galaxy cluster.[4]
They published their findings in a paper in 1970 which gained a lot of attention from researchers all around the world.
And that is how Vera Rubin along with Kent Ford ended up discovering the second evidence of the existence of dark matter which proved to reignite the interest of scientists in dark matter after years of it being hidden in the shadows.
Vera Rubin’s Legacy
Together with Kent Ford, Rubin developed the Rubin-Ford effect, a technique for accurately measuring galaxy rotation curves.
This method has since become a standard tool in astrophysics for studying the dynamics of galaxies.
In 2000, her view on the history of the work on galaxy movements was presented in a review, “One hundred years of rotating galaxies” for the Publication of the Astronomical Society of the Pacific.
In 2002, she was listed as one of the 50 most important women in science by Discover Magazine.[5]
The Large Synoptic Survey Telescope underwent a name change to become the National Science Foundation Vera C. Rubin Observatory on December 20, 2019.
The observatory is situated atop Cerro Pachón in Chile and has a primary mission of investigating dark matter and dark energy.
In tribute to Vera Rubin’s contributions, the Carnegie Institute has established a postdoctoral research fund, and the Division on Dynamical Astronomy of the American Astronomical Society has introduced the Vera Rubin Early Career Prize, both dedicated to perpetuating her legacy in the field of astronomy.
Vera Rubin’s work has had a profound and lasting impact on the field of astrophysics. She is one of the astronomers who paved the way for women in the field.
References
- BBVA Openmind, ‘Vera Rubin and Dark Matter’, 25 December 2017, https://www.bbvaopenmind.com/en/science/leading-figures/vera-rubin-and-dark-matter/[↩]
- CWB, ‘Vera Cooper Rubin’, https://web.archive.org/web/20130424105951/http://www.physics.ucla.edu/~cwp/Phase2/Rubin%2C_Vera_Cooper%40931234567.html[↩]
- Sarah Scoles, ‘How Vera Rubin confirmed dark matter’, Astronomy.com, 4 October 2016, https://www.astronomy.com/science/how-vera-rubin-confirmed-dark-matter/[↩]
- Smithsonian, ‘Meet Vera Rubin’, 17 November 2021, https://airandspace.si.edu/stories/editorial/meet-vera-rubin[↩]
- Kathy A Svitil, ‘The 50 Most Important Women in Science’, Discover, 1 November 2002, https://www.discovermagazine.com/the-sciences/the-50-most-important-women-in-science[↩]
