Board Thread:General Discussion/@comment-103.206.114.214-20170618105440/@comment-27345308-20170618110654

On the file description says the image is in public domain. If you don't trust the file description (as in, if you think the uploader didn't think too much about the image's licensing and just selected "public domain" without thinking), you can contact the user that uploaded it. Oldest occurence of that image I could find through a reverse Google image search is this one (although blue) from 2003, and the image is used already on a lot of places so I believe the image really is in public domain.