On March 6, 1969, Dave Scott, Rusty Schweickart, and Jim McDivitt tested docking the Apollo 9 Command and Services Module docked with the lunar module. Or, Gumdrop met Spider in a late test that shuffled around crews, changing who would land on the moon.
https://observationdeck.kinja.com/todays-space-trivia-spiders-first-flight-1538784362
