About This Stamp
This Forever® stamp from the U.S. Postal Service honors Dr. Chien-Shiung Wu (1912–1997), one of the most influential nuclear physicists of the 20th century.
The stamp art features a detailed portrait of Wu — drawn first in graphite and then rendered in egg tempera paint — wearing a black-and-white high-collared, traditional Chinese gown known as qipao. The background was painted with the pigment lapis lazuli, an ancient, highly valued color historically used in artistic depictions of angels, nobility, and the Virgin Mary.
During a career that spanned more than 40 years in a field dominated by men, Wu established herself as the authority on conducting precise and accurate research to test fundamental theories of physics.
In 1944, Wu accepted a position under the Division of War Research at Columbia University working on uranium enrichment and radiation detectors for the Manhattan Project. Conducting highly classified research for the production of the world’s first atomic bomb, Wu made invaluable contributions to the experimental process of splitting and harnessing the power of the uranium atom.
After the war ended, Wu stayed on at Columbia as a research professor, focusing her experimentation on beta decay. With ingenuity and careful research, she created a more precise spectrometer to finally explain the problem of beta decay, one that had plagued physicists in America and across Europe for decades.
In 1956, theoretical physicists Tsung-Dao Lee and Chen-Ning Yang approached Wu for help in developing a theory that disproved the foundational principle of conservation of parity. Wu created a thoughtful and intricate experiment to test the theory. She observed that, in weak interactions, parity is not conserved—a finding that overturned a decades-old, intrinsic element of quantum mechanics and earned the lead physicists the Nobel Prize in Physics.
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. This Forever stamp will always be equal in value to the current First-Class Mail® one-ounce price.
Note: The spelling of Wu's name on the stamp reflects how she wrote her own name and referred to herself. It is also how she was known to the scientific community at large. This romanized spelling of her name is based on the Wade-Giles system, which is all but obsolete for Chinese words and names. The Pinyin system is now the standard in both China and the United States.
Stamp Art Director, Stamp Designer
Ethel Kessler
Ethel Kessler is an award-winning designer and art director who has worked with corporations, museums, public and private institutions, professional service organizations, and now, the United States Postal Service.
After earning a B.F.A. in visual communications from the Maryland Institute College of Art, Kessler worked as a graphic designer and project manager for the exhibits division of the United States Information Agency. Her work was distributed internationally on subjects such as Immigration, Entrepreneurship, Renovation of American Cities, and the Bicentennial of 1976. She was also responsible for exhibits in Morocco, Botswana, and El Salvador.
In 1981, she established Kessler Design, Inc., for which she is creative director and designer. Clients have included the Clinton Government reorganization, the Smithsonian Institution, National Geographic Television, the National Park Service, and the American Institute of Architects.
She has been an art director for the U.S. Postal Service’s stamp development program for more than 25 years. As an art director for USPS, Kessler has been responsible for creating more than 500 stamp designs, including the Breast Cancer Research stamp illustrated by Whitney Sherman. Issued in 1998, the stamp is still on sale and has raised more $98 million for breast cancer research. Other Kessler projects include the popular and highly regarded Nature of America 120 stamp series, a collaboration with nationally acclaimed nature illustrator John Dawson, the 12-year Lunar New Year series with Kam Mak, the American Filmmaking: Behind the Scenes 10 stamps issued in 2003, a 2016 pane of stamps celebrating the 100th anniversary of the National Park Service, and the 2023 stamp honoring Supreme Court Associate Justice Ruth Bader Ginsburg. And many, many others.
Stamp Artist
Kam Mak
Kam Mak was born in Hong Kong and grew up in New York City’s Chinatown after his family moved to the United States in 1971. Kam’s involvement with cityArts Workshop, an organization designed to encourage the art interests of inner city youth, inspired his love of painting. He earned his bachelor of fine arts degree in 1984 from New York’s School of Visual Arts where he studied on a full scholarship.
Mak’s richly colored paintings have illustrated the covers of numerous magazines and books including his first offering as both author and illustrator, My Chinatown: One Year in Poems, about a little boy growing up in Chinatown.
For his award-winning illustrations Mak has received the Oppenheim Toy Portfolio Platinum Book Award for best children’s picture book, the National Parenting Publications Gold Medal, and the Stevan Dohanos Award and both gold and silver Medals from the Society of Illustrators. In addition to My Chinatown, books for which he won acclaim include The Dragon Prince by Laurence Yep, The Kite Rider by Geraldine McCaughrean, The Year of the Panda by Miriam Schlein, and The Moon of the Monarch Butterflies by Jean Craighead George.
Mak is a professor at the Fashion Institute of Technology. He is currently working on a series of figurative and still-life paintings, using the medium of egg tempera, a process that uses egg yolk to bind pigments. He lives in Brooklyn, New York, with his family.
Mak was commissioned by the U.S. Postal Service to design the 12-year stamp series Celebrating Lunar New Year that began in 2008 and has continued through 2019. His most recent stamp design features Dr. Chien-Shiung Wu (2021).