Beatrice Tinsley: the Astrophysicist Who Showed the World How Galaxies Are Born

At a time when women were not encouraged to participate in scientific fields, British-born immigrant Beatrice Tinsley not only succeeded, but dominated in the fields of astronomy and cosmology. Scientists credit Tinsley with much of the research that informs our understanding of how galaxies evolve, develop and die out.

Tinsley’s Upbringing

Born in Chester, England to a family of three sisters, her family moved to New Zealand after WWII. She was brilliant in high school: math, languages, writing and music. Music was a huge passion for her; she played violin for the National Youth Orchestra. Tinsley was the first female student to apply for her high school’s math scholarship, and win it.

She was interested in astrophysics in her teens, and attained both her Bachelor of Science and her Master of Science degrees at the University of Canterbury by the age of 20. Tinsley noted that there were less than 10 girls in her lecture classes of over 100 students.

She married a fellow physics classmate, Brian Tinsley. Since her husband already worked at their university, the physics department denied her a job. She and her husband were both brilliant in the field of astronomy, but Tinsley was systematically ignored.

Tinsley’s case illustrates a problem for women that stemmed from a common university policy prohibiting the hiring of spouses of existing faculty. Universities commonly employed this method to keep women out of faculty ranks.

The Move to the United States

When her husband received a job offer at the South West Centre for Advanced Studies in Dallas, TX (which is now part of the University of Texas, Dallas), the couple relocated to the United States. In the very male-oriented culture of Dallas, Tinsley could not find a job. She took up a part-time teaching position at the University of Texas at Austin, over 200 miles away.

Tinsley received a scholarship to do her Ph.D. at the University of Texas at Austin, so her husband moved with her. Here, they adopted two children.

Tinsley’s Ph.D.

Even though she was the sole female doctorate student in astronomy, she finished her program in just two years. She titled her Ph.D. thesis “Evolution of Galaxies and its Significance for Cosmology” and her professors described the paper as “extraordinary and profound”.

Though she was the first student in the astronomy program to receive marks over 80 percent (she received a 99 and 100 percent on her work), she was unwelcome in the faculty arena of academia due to her gender. She faced the same problem as she had in New Zealand: since she was a woman, she could not find meaningful astrophysics work. The school did not even answer her application for head of the department.

Work on Galaxy Evolution

Tinsley persisted in astrophysics research for the next few years, struggling to juggle her disappointed career ambitions and duties as a wife and mother.

From her work, we now know that galaxies experience significant changes over a relatively short span of time. Tinsley also proved that determining distances of galaxies by a technique called morphology was unreliable.

Up until then, astronomers assumed that galaxies of the same type would be of a similar size, shape and luminosity. In morphology, astronomers compared sizes and luminosities of far-off galaxies to those nearby whose distances we already had ascertained, and used this comparison to figure out the distance of the far-off galaxies. Tinsley proved that this was an inaccurate method of measurement.

Tinsley’s work is now the basis of contemporary studies of galactic evolution. The models she built were more realistic than any astrophysics had at the time. With her galactic modeling, the world could envision what galaxies in their infancy might look like.

In 1974, the American Astronomical Society and the American Association of University Women awarded Tinsley the Annie J. Cannon Prize. This award recognized women under 35 with potential for significant research in the field of astronomy.

Breaking Point

The year Tinsley accepted the Annie J. Cannon Prize, she reached her breaking point. She could no longer have her ambitions stifled. Tinsley sought a divorce from her husband and left Texas and her children—who her husband received full custody of—for a one-year position as a Fellow at the Lick Observatory at the University of California, Santa Cruz.

After her fellowship, Yale University hired Tinsley as an assistant professor, and three years later, Yale promoted her to a full-time Professor of Astronomy.

Sadly, in the few years that followed this assignment, the final realization of her dreams, Tinsley discovered she had melanoma. On March 23, 1981, she died. Apparently, she believed that the guilt and trauma she felt in abandoning her children triggered her cancer.

Posthumous Appreciation

In her 14-year academic career, Tinsley published some 100 papers. Women in the sciences credit her with tremendously valuable mentorship as a teacher and researcher.

In 1986, American Astronomical Society posthumously honored her by establishing the Beatrice M. Tinsley Prize for outstanding creative contributions to astrophysics or astronomy.

Mt. Tinsley from Lake Manapouri in New Zealand

The University of Texas at Austin, her alma mater, also created the Beatrice M. Tinsley Visiting Professorship in astronomy.

In 2011, New Zealand formally acknowledged Tinsley’s achievements and the New Zealand Geographic Board named a Fiordland mountain Mt. Tinsley after her.

Unfortunately, Tinsley was just too early for her time. Her contributions, even as she pushed back as a female immigrant in an aggressively male-dominated field, will not be forgotten by the scientists of today.