Apollo 8 artifacts, Command Module replica
The actual Command Module from Apollo 8 carried the astronauts home to Earth and is on exhibit today at the Museum of Science and Industry, in Chicago. It really went out to orbit around the Moon on Christmas, 1968. That was the first time (as far as we know) that humans had been primarily under the gravity of something other than the Earth.
Apollo 8's CM is scorched from the heat of re-entry into the Earth's atmosphere., this replica is pristine, as the real one looked at Christmas Eve. The real Apollo CMs were covered in reflective aluminized Mylar with the pieces the same size, shape and location as this replica has.

In his wonderful book, "Carrying the Fire", Apollo 11 CM Pilot Michael Collins writes movingly about his troubled relationship with the probe mechanism at the front of the CM. He was responsible for using the probe to latch onto a matching 'drogue' on the Lunar Module. After the probe and drogue pulled the two spacecraft together, 12 smaller latches around the circumference of the docking tunnel locked them. Hence the two red circles outside the tunnel, which represent silicon rubber o-rings that seal the connection. Then Collins had to open the hatch and remove the probe assembly, then he or the Lunar Module pilot (Buzz Aldrin) would remove the drogue assembly from the LM end of the tunnel and only then could the LM's hatch be opened and the crew move back and forth between the two vessels.
When the LM and CM disconnected, so the LM could land on the moon, the whole business had to be repeated backward so the probe and drogue were installed correctly when the hatches were closed...

the "1968" exhibit at the Oakland Museum of California.
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