I don't know what I shall think about the UFO phenomenon as I have no personal experience in that field but I think it's important enough to offer ONE explanation to the long-lasting stripes in the sky.
Last registration of the "Center for Global Peace": April 8th 2011: https://web.archive.org/web/20110408125746/http://www1.american.edu/academic.depts/acainst/cgp/ longlink.com