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.
Keywords from Image Description:
Trouvelot The planet Mars . The planet Mars Observed September at Plate VIII from The Trouvelot Astronomical Drawings The drawing features are described in the following work citation tienne Lopold Trouvelot The Trouvelot astronomical drawings manual Charles Scribner's sons New York google id rjisAAAAIAAJ pg PA nypl org