I saw how Banksy authenticates his work, and we got to thinking about how we verified things in the past, and future. https://reprage.com/post/how-banksy-authenticates-his-work https://en.wikipedia.org/wiki/EURion_constellation Can you please fill out our podtrac survey: http://survey.podtrac.com/start-survey.aspx?pubid=B8NmaYB8k-kH&ver=short