How Did Harriet Brooks Contribute to the Atomic Theory?


Jane Flores

Harriet Brooks was a Canadian physicist who lived from 1876 to 1933. She made significant contributions to the field of atomic theory during her lifetime. Despite facing many obstacles in her career due to gender discrimination, she remained dedicated to her work and made several important discoveries that helped shape our understanding of the atom.

The Early Years

Harriet Brooks was born in Exeter, Ontario, Canada, in 1876. She attended the University of Toronto, where she studied under famed physicist J.J. Thomson. Brooks was one of only a few women studying physics at the time, and she faced many challenges due to gender discrimination.

Despite these obstacles, Brooks excelled in her studies and eventually became Thomson’s research assistant. She worked with him on several experiments related to cathode rays and radioactivity.

Discovering New Elements

In 1901, Brooks made a groundbreaking discovery while working on an experiment with radioactive materials. She discovered a new element, which she named “radium emanation.” This element was later identified as radon, a gas that is highly radioactive.

Brooks’ discovery of radon was significant because it provided scientists with a new tool for studying radioactivity. It also helped confirm the existence of subatomic particles within atoms.

Further Contributions

Over the next few years, Brooks continued to make important contributions to atomic theory. She conducted experiments that helped identify the different types of radiation emitted by radioactive materials and helped develop methods for measuring their intensity.

In 1904, Brooks became one of the first women to receive a Master’s degree in physics from the University of Toronto. She went on to teach physics at Barnard College in New York City before retiring from academia in 1928.


Despite facing many challenges as a woman working in physics during the early part of the 20th century, Harriet Brooks made significant contributions to the field of atomic theory. Her discovery of radon helped scientists better understand the nature of radioactivity, and her work on measuring radiation intensity laid the foundation for future research in the field.

Today, Brooks is remembered as a pioneer in her field and an inspiration to women who aspire to careers in science. Her contributions to atomic theory helped shape our understanding of the building blocks of matter and opened up new avenues for scientific exploration.