An excellent article in my local paper, the
Manawatu Standard, of Palmerston North, New Zealand, Thursday 25 June 2015, page 11. It uses information printed in many other sources.
http://www.pressreader.com/new-zealand/manawatu-standard/20150625/281865822117890/TextViewI recall that before July 1969, there were fears being expressed about lava tubes on the moon being a hazard to astronauts, and Mike Collins commented briefly on them in his book,
Carrying the Fire, page 410:
"How goes it anyway?" "Roger, Columbia... the crew of Tranquility Base is back inside... everything went beautifully." "Hallelujah!" Well, that's a big one behind us: no more worrying about crashing through into hidden lava tubes, or becoming exhausted, or the front door sticking open, or the little old ladies using weak glue, or any of that! Whew!
