The delta was first used in space organizations as early as 1961 and has inspired generations of space professionals. #sempersupra pic.twitter.com/SwV3LEFRss— United States Space Force (@SpaceForceDoD) July 22, 2020
The delta was first used in space organizations as early as 1961 and has inspired generations of space professionals. #sempersupra pic.twitter.com/SwV3LEFRss