text: Though mostly forgotten today, piloted free-return flyby missions to Mars and Venus in partnership with robot probes were a major theme of NASA advance planning in the 1960s.
  
  They are a pet topic of mine.
  
  From my blog No Shortage of Dreams. 🛰️🔭🧪🚀🪐🌏👩‍🚀🌌
  
  spaceflighthistory.blogspot.com/2015/12/miss...