Margaret Rossiter's Life and Work Brought Women Scientists to Light

Margaret Rossiter wouldn't listen. 

She once asked a group of mostly male professors and students in the history of science department at  Yale if there were ever any women scientists, as they had never been discussed this at these regular monthly gatherings.

"No," they answered. "None." Someone hedged that Marie Curie might be an exception. And that was that.

Rossiter didn't listen to these responses. She didn't believe that women scientists hadn't played a role in the history of American science. She spent the next fifty years of her career disproving that sentiment and chronicling the contributions of women in science.

Margaret W. Rossiter in 1989.
 Office of Visual Services (UREL), Cornell University.

Rossiter was born in Malden, Massachusetts. She became interested in the history of science in high school. She attended Radcliffe and graduated with a degree in the history of science, then earned master's degrees from the University of Wisconsin-Madison in the same field, and in philosophy at Yale, where that famous conversation about women scientists took place. She stayed at Yale to complete her PhD, where she worked on agricultural science.

While agricultural science was the focus of her first published work, Rossiter still gravitated to the idea that women scientists did exist and played an important part in the development of science. She began researching this idea and delved into writing her first book on the history of women in science, Women Scientists in America, Struggles and Strategies to 1940, published in 1984. Rossiter followed that book with two more: Women Scientists in America: Before Affirmative Action, 1940–1972, published in 1995, and Women Scientists in America Volume 3: Forging a New World Since 1972, published in 2012.

Rossiter wrote the first book while juggling a series of visiting professorships and grants, as she struggled to find a tenured position. At one point, she said she identified with those women scientists who also struggled. Rossiter finally found tenureship at Cornell where, after two years as a visiting professor, Cornell gave her an endowed chair in their new Department of Science and Technology. 

Rossiter was the recipient of many grants and awards throughout her career, including the Guggenheim Fellowship, the MacArthur Fellows Program, the Women's Prize from the History of Science Society, and the George Sarton Medal. The Women's History Prize was eventually renamed in her honor. 

In addition, Rossiter coined the phrase "the Matilda effect" to refer to the tendency within science to attribute women scientists' discoveries to their male counterparts. In doing so, she drew attention to this bias in science.

In 2019, Smithsonian Magazine featured Rossiter and the immediate impact of her work on women in STEM, saying, "In excavating the lives of forgotten women astronomers, physicists, chemists, entomologists and botanists, Rossiter helped clear the way for women scientists in the future." Read more from that article at Smithsonian Magazine.

Margaret Rossiter died August 3, 2025, after a long career in supporting women in science and preserving their stories and rightful places in history. 

Read more about Rossiter's life at the Cornell Chronicle or the New York Times. 

Remembering Amber Stuver

By Members of the CSWA

Amber Stuver, 1978-2024

We are saddened to share the news that Dr. Amber Stuver has passed away. Amber was an astronomer, faculty member at Villanova University, and member of the CSWA.

We remember Amber fondly, both as an enthusiastic supporter and advocate for the advancement of women in Astronomy and for her work in championing and promoting the needs of women from historically marginalized groups. Her work on the CSWA was tireless and invaluable. Amber was a genuinely kind person who was generous with her time, always willing to volunteer and was someone who could be counted on to help students and colleagues alike.  She will be missed professionally and personally.

Add your remembrances of Amber at:

https://www.legacy.com/us/obituaries/triblive-tribune-review/name/amber-stuver-obituary?id=56299141

Remembering Sheila Tobias

By Meg Urry

Dr. Meg Urry is the Israel Munson Professor of Physics and Astronomy, and Director of the Yale Center for Astronomy and Astrophysics; she previously served as Chair of the Physics Department at Yale from 2007 to 2013 and in the Presidential line of the American Astronomical Society 2013-2017. Dr. Urry is also known for her efforts to increase the number of women and minorities in science, for which she won the 2015 Edward A. Bouchet Leadership Award from Yale University and the 2010 Women in Space Science Award from the Adler Planetarium. She served on the CSWA from 1994 - 2003.

Sheila Tobias speaks at West Virginia University.
Credit: Julie Black, Teaching and Learning Commons, WVU

I was shocked to learn that Sheila Tobias died a year ago (NY Times obituary). She was a noted feminist with particular ties to, and affection for, the physical sciences. She wrote influential books on why so few women studied physics and math, including They’re Not Dumb, They’re Different and Overcoming Math Anxiety. She was married to a physicist, Carl Tomizuka and would sometimes attend meetings of the American Physical Society (APS). 

Most importantly for astronomers, she was a featured speaker at the 1992 Women in Astronomy meeting, at the Space Telescope Science Institute, in Baltimore, Maryland. I still remember sitting at the front of the lecture hall, listening to Sheila teach Feminism 101 in one riveting hour. I was simultaneously exhilarated (what clarity! the professoriate began in monasteries! the tropes of celibacy and singular focus and the sense of a “calling” are with us still) and terrified that the men in the room would be turned off by this challenge to their supposed meritocracy. But when the talk ended and I turned around, I saw only excited, smiling people. Riccardo Giacconi and other STScI leaders later raved about her lecture. She was able to deliver tough medicine in a way people responded well to, and she had a huge impact that day.

After the meeting, she wrote the first draft of the Baltimore Charter, based on notes from the breakout sessions. It was she who introduced the metaphor of great civilizations (innovations) arising at the juncture of trade routes (where differing ideas could connect). I think of that metaphor often, and indeed, there is considerable research today about innovation arising from difference. She had such a wide-ranging mind and piercing intellect that she broadened the way others think.

I learned so much from Sheila. Once, at an APS meeting somewhere, we were having a drink after dinner, and I guess I complained about how hard it was to be a woman in the overwhelmingly male world of physics. Didn’t she think that was a terrible disadvantage for women? “Oh no,” she answered immediately, “I wouldn’t have it any other way.” She explained that by virtue of being outsiders, women had occasion to understand themselves and their relation to others, and that this was something men, swimming in a pool of other similar men, didn’t often think to do. She said that she would never trade the self-awareness earned by outsiders for the complacency of the majority class. I’ve thought often about that sentiment, and it has buoyed me on many occasions. 

I did not know Sheila was unwell. When I saw her a few years ago, she was in wonderful health. And then COVID cut many of us off from one another, and I guess she succumbed to the downstream consequences of a fall. It’s great the New York Times recognized her contributions. With this post, I wanted to make sure that astronomers, in particular, remember how much she did for us.

Read more about Sheila Tobias and her work:

Sheila Tobias on her nonscience path to becoming a science activist, Physics Today

AASWomen Newsletter for August 19, 2022

AAS Committee on the Status of Women
Issue of August 19, 2022
eds: Jeremy Bailin, Nicolle Zellner, Alessandra Aloisi, and Sethanne Howard

[We hope you all are taking care of yourselves and each other. --eds.]

This week's issues:

Leisa Townsley, 1964-2022

1. Passing of Dr. Leisa Townsley 
2. Special Message on Dobbs v. Jackson Women's Health Organization
3. Seeking Co-Chairs for Cross-AG IDEA Working Group
4. Two New Books!
5. How to Submit to the AASWomen Newsletter
6. How to Subscribe or Unsubscribe to the AASWomen Newsletter
7. Access to Past Issues of the AASWomen Newsletter

An online version of this newsletter will be available at http://womeninastronomy.blogspot.com/ at 3:00 PM ET every Friday.

Passing of Dr. Leisa Townsley

By Eric Feigelson, Sarah Gallagher, and Ann Hornschemeier Cardiff  

With great sadness, we have learned of the passing of Dr. Leisa Townsley.  She passed away peacefully in Colorado, after a battle with cancer, on Monday August 8th with her life-long partner Pat Broos at her side. She worked at Penn State for more than 28 years as a leader and, subsequently, the Penn State PI, for the Chandra ACIS instrument. She and Pat had relocated to Utah, and then Colorado in 2014 to work remotely for Penn State in anticipation of their retirement there.  

1964-2022 (legacy.com)

Leisa had a rich and substantial character and demonstrated fundamental integrity as a person and a scientist. She was greatly respected and will be deeply missed by the high-energy astrophysics community and others who knew her.

Her talents as a scientist were  truly remarkable. She helped establish the importance of X-ray studies of massive star-forming regions using Chandra and other observatories. She published Chandra catalogs of tens-of-thousands of young stars in dozens of clusters and associations, and she discovered diffuse X-ray emission in all regions arising from colliding OB-star winds. This work required the careful and comprehensive removal of point sources, accomplished using the superb ACIS Extract software package that Pat Broos and she developed. Her research invalidated the century-old belief that HII regions are suffused with 10^4K gas, finding they are instead filled with 10^7K gas with H-alpha produced only at the cloud surface. Leisa’s work helped establish the ‘birth of the hot interstellar medium’ that fills most of the Galactic disk, showing that the hot ISM from winds precedes the more spectacular supernova remnants. 

Colleagues have remarked on conversations with Leisa after she completed analysis of these regions, showing spectacular and unique color images of diffuse Chandra X-rays filling the gaps between Spitzer molecular clouds. These were views of how star formation was operating that led to conversations that no one in the world had been able to have prior to her work. She was a pioneer forging in directions that were enabled by the combination of her fundamental understanding of high energy astrophysics and her deep knowledge of the ACIS instrument. But this work only represents only part of her accomplishments: calibrating the ACIS instrument (she created the first model used to correct the charge-transfer inefficiency from the early CCD radiation damage), leadership of the 1 Ms mosaic of the Carina Nebula resulting in a book-length issue of the ApJ Supplement Series, constructively leading and participating in dozens of other Chandra studies, management of Chandra affairs at Penn St​ate, and more. Her death is a great loss.  

Aside from her professional excellence, Leisa, and her partner Pat, mentored a generation of Penn State graduate students and postdocs, in a manner that could be described as “aggressive welcome". She generously sat through many practice talks to give feedback, and improved the communication skills of a host of early career researchers. She made sure that new scientists appreciated the skill and effort required to characterize an instrument so that results could be trusted. She invited early career high-energy astrophysicists (and many others) into her home on a routine basis. Colleagues from outside Penn State would remark on having been invited to an informal pizza party at her house, only to arrive at her warm and welcoming abode, people wandering around in the yard, with two very happy dogs co-hosting the party. In an era when we are working on improving the culture of our field, Leisa Townsley embodied the ultimate goal:  to greet everyone warmly and to celebrate, and encourage, the scientific success of everyone. She acknowledged and respected the contributions of all team members and was a savvy leader who understood people well and brought out their best work. One of the Penn State grads commented on having invited her and Pat to an awards banquet some years after graduation and that Leisa remarked she wasn’t that important. To a generation of early-career folk at Penn State, Leisa wasn’t merely important, she was the reason they made it through. Her legacy is not only her impactful contributions to our understanding of star-forming regions, but the people in the community who are here, contributing and leading, thanks to her support and her example.

Please see the testimonial from the Penn State Department of Astronomy and Astrophysics, and please share your memories of Leisa in the Comments below.