Public Domain
Public Domain is a copyright term that is often used when talking about copyright for creative works. Under U.S. copyright law, individual items that are in the public domain are items that are no longer protected by copyright law. This means that you do not need to request permission to re-use, re-publish or even change a copy of the item. Items enter the public domain under U.S. copyright law for a number of reasons: the original copyright may have expired; the item was created by the U.S. Federal Government or other governmental entity that views the things it creates as in the public domain; the work was never protected by copyright for some other reason related to how it was produced (for example, it was a speech that wasn't written down or recorded); or the work doesn't have enough originality to make it eligible for copyright protection.
Citation
Palmer, Alfred T. This girl in a glass house is putting finishing touches on the bombardier nose section of a B-17F navy bomber, Long Beach, Calif. She's one of many capable women workers in the Douglas Aircraft Company plant. Better known as the "Flying Fortress," the B-17F is a later model of the B-17 which distinguished itself in action in the South Pacific, over Germany and elsewhere. It is a long range, high altitude heavy bomber, with a crew of seven to nine men, and with armament sufficient to defend itself on daylight missions. Photograph. Washington, D.C. October 1942. Library of Congress. https://www.loc.gov/pictures/item/2017878928/