Langsdorf, 96, had been suffering from a lung infection, the Chicago Tribune reported. She died last Tuesday at a facility near her home in the suburb of Schaumburg, Ill.
As an artist, Langsdorf had almost 100 solo shows and her work was exhibited at the Whitney Museum of American Art in New York, the Art Institute of Chicago and the Brooklyn Museum. But it was the Atomic Clock, created for the first issue of the Bulletin of Atomic Scientists in 1947 and inspired by her husband's work with the Manhattan Project helping develop the first atomic bombs, that was her best-known creation.
"She understood the deep anxiety of the scientists in 1947, and the urgency of preventing the spread or use of nuclear weapons," Kennette Benedict, the Bulletin's current executive director, said. "With the clock design, she gave the world a symbol that is even more potent today."
Langsdorf was born in St. Louis, where her father was a portrait photographer and her mother an artist. As a child, she showed talent in both music and art.
Her family said she fixed on an artistic career in her teens when she sold a painting to composer George Gershwin.
Langsdorf graduated from Washington University and married physicist Alexander Langsdorf, who joined the Manhattan Project two years later.
The Printworks Gallery in Chicago plans an exhibit of Langsdorf's work, "Works on Paper and Mylar, 1967-2012" from May 3 to June 8.