Chien-Shiung Wu Featured on USPS Forever Stamp

Thursday, February 4, 2021

The US Postal Service has revealed a new stamp design honoring Chien-Shiung Wu, a Chinese-American experimental physicist who made significant contributions in the field of nuclear physics.

Wu, who was born and raised in China, came to America at the age of 24 and studied at the University of California, Berkeley where she met her husband. During her graduate studies, Wu worked at the Radiation Laboratory, directed by Ernest O. Lawrence. While at Berkeley, she also worked closely with Emilio Segrè. Wu completed her PhD in June 1940 with honors. In spite of Lawrence and Segrè's recommendations, she could not secure a faculty position at a university, so she remained at the Radiation Laboratory as a post-doctoral fellow.

In March 1944 Wu joined the Manhattan Project, where she helped develop the process for separating uranium into uranium-235 and uranium-238 isotopes by gaseous diffusion. She is best known for conducting the Wu experiment, which proved that parity is not conserved. This discovery resulted in her colleagues Tsung-Dao Lee and Chen-Ning Yang winning the 1957 Nobel Prize in Physics. Wu's role in the discovery was not publicly honored until 1978 when she was awarded the inaugural Wolf Prize.

In 1946, she served in the Physics Department of Columbia University as a research associate until 1952. From 1952-58, Wu was an associate professor and then became a professor until she retired in 1981 as a Michael I. Pupin Professor of Physics. In her research at Columbia, Wu also worked to develop improved Geiger counters for measuring nuclear radiation levels. As a professor, Wu taught at both Princeton and Columbia Universities.

Professor Wu was the recipient of numerous awards for her work, including eight honorary degrees, the National Medal of Science (1975), and the first person selected to receive the Wolf Prize in Physics (1978). She is also the first female President of the American Physical Society. 

"She was very influential," said Herbert Steiner, a professor emeritus in physics at UC Berkeley and senior faculty scientist at Lawrence Berkeley National Laboratory. "She was a pioneer and did a lot for women's rights."

She earned many nicknames for her expertise, including the “Chinese Madame Curie,” the “Queen of Nuclear Research” and the “First Lady of Physics.”


The Stamp

Art director Ethel Kessler designed the stamp with original art by Kam Mak. The Chien-Shiung Wu stamp is being issued as a Forever stamp in panes of 20. These Forever stamps will always be equal in value to the current First-Class Mail 1‑ounce price. The stamp is available for pre-order and will be released on Thursday, February 11, 2021.

A virtual ceremony will be carried on the Postal Service's Facebook and Twitter channels on Thursday, February 11, 2021 at 11:00 am EST. Please note that you must first "like" the page before you will be able to view the ceremony.

Keith Burbank
Robert W. Kelly