RT @NASAhistory: #OTD 1987, Venera 16 entered orbit around Venus, beginning a 1-year mission to radar map its northern polar region.… twitter.com/i/web/status/7…
RT @NASAhistory: #OTD 1987, Venera 16 entered orbit around Venus, beginning a 1-year mission to radar map its northern polar region.… twitter.com/i/web/status/7…