This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Tsiolkovsky with his steel dirigibles. en Konstantin Tsiolkovsky with models of his steel dirigibles ru ruscosmos ru Unknown due to age PDRusEmpire Konstantin Tsiolkovsky
Page 2023 Free-images.com. All images are Public Domain