Her mother was the painter Aimee Schweig and her father was the portrait photographer Martin Schweig, Sr.[2] As a young woman she attended painting classes with her mother, first at the Provincetown Art Colony (Provincetown, Massachusetts), and then at the Ste.

Alexander helped found the Bulletin of the Atomic Scientists in 1945 and in 1947 Martyl created the Doomsday Clock image for their first June 1947.

She thought a clock, set at seven minutes to midnight, would convey "a sense of urgency.

[6] Designed by Paul Schweikher and built in 1938,[7] Schweig Langsdorf lived and worked there until her death.

[8] Schweig Langsdorf died of complications of a lung infection in Schaumburg, Illinois.