This image was acquired from
flickr. 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:
mars nasa space science geology astronomy university of arizona universityofarizona texture abstract outdoor Ancient Rivers Early in Martian history liquid water energetically carved the surface forming channel systems that look remarkably similar to river valleys and drainage networks on Earth. NASA of Arizona Ancient Rivers Early