What do you know today that you didn't know yesterday?

[Anomalocaris]

Apollo astronauts who investigated lunar geology on the surface carried procedure check list for their tasks as laminated flip cards attached to their space suit sleeves.    For one of the missions, I can’t recall which at the monument,  the backup crew, who trained together with the primary crew and acted as support for the main crew during pre-launch prep, replaced the procedural flip cards with nude photos of various playmates of the month as a prank.   The prank was not discovered until the primary crew was on the surface of the moon.

The primary crew played it cool, remembered the procedures and did not reveal on air what actual mountains and valleys they were actually looking at when they were supposed to be looking at geology field work check lists.

The playmates of the month photos made it back to earth and are currently catalogued in nasa’s historic mission archives