SRS non-mission date with ship photo

Space event covers, in contrast to First Day or commemorative envelopes, are used by astrophilatelists to tell the story of the exploration of the heavens with postage stamps. Unlike thematic or topical collecting, it is the postmark with the correct date and the nearby post office location adjacent to the controlling event, which tells the story. This envelope is from the NASA Apollo program which ran from 1961-1975.