The NPR.org news item Meet John Houbolt: He Figured Out How To Go To The Moon, But Few Were Listening shows the iconic photo of John Houbolt next to a black board showing a free return scenario.
I have always wondered why arrow #5 (top one near the Moon) appears to be pointed the wrong way, and recently I realized that #6 does as well. Why is this?
If it doesn't indicate the direction of spacecraft motion, what does it point towards?
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American aerospace engineer John Houbolt as he stands at a chalkboard in July 1962 showing his lunar orbit rendezvous plan for landing astronauts on the moon.