So then. What were the last -- really the last -- words?
According to Apollo 7 astronaut Walter Cunningham in his book The All-American Boys, Cernan's final words on the moon were: "Let's get this mother out of here." (Or as O'Brien spells it, awesomely, "let's get this mutha.") And there would be, indeed, something wonderfully poetic about "let's get this mother" -- excuse me, mutha -- "outta here" as our parting words to the moon: something very human and honest and inscribed in its time.
But the "outta here" thing is likely, alas, apocryphal. According to NASA's official transcript of Apollo 17's return to Earth, what Cernan actually said was in part a response to a malfunction his fellow astronaut, Jack Schmitt, was encountering with a camera: "Now, let's get off. Forget the camera."
This was followed by a countdown and, alas, due to some other minor equipment malfunctions, static. But not, at least per the transcript, with any mention of mothers. "During the mission review in Santa Fe," NASA mentions as an aside in that transcript, "Gene was surprised not to hear those words" -- because Cernan himself recalled his final words they way Cunningham had quoted them. However, NASA continues: "What seems likely is that what he was remembering was his at 188:01:25 [the "let's get off" moment in the transcript] and that, in later tellings, the wording changed to the more colorful version Cunningham quotes."
Here's the relevant section of the transcript:
188:00:38 Cernan: Take your final look at the valley of Taurus-Littrow, except from orbit. (Pause) Okay, one minute, Houston. We're 50 seconds now, and we're Go.
188:00:51 Fullerton: Roger. You're looking good here.
188:00:55 Schmitt: I'll get that (camera) at 30.
188:00:57 Cernan: Okay. (Pause)
188:01:10 Schmitt: Camera's not going to run without me holding it.
188:01:20 Cernan: Okay. Average G, 20 seconds.
[Cernan - "This was a routine in the PGNS to start recording data from the accelerometers."]
188:01:23 Schmitt: Ah, shoot!
188:01:25 Cernan: Okay. Now, let's get off. Forget the camera. (Garbled)...
MPEG Clip by Kipp Teague (30 sec; 3.9 Mb)
188:01:27 Schmitt: Ten seconds.
188:01:28 Cernan: ...10 seconds.
188:01:29 LM Crew: Abort Stage.
188:01:30 Cernan: ...pushed. Engine Arm is Ascent.
188:01:32 Schmitt: Okay. I'm going to get the Pro. (Pause) 99 Proceeded 3, 2, 1...
188:01:39 Schmitt: Ignition.
So there it is -- sort of. "Let's get off."
But could the garbled section of the transcript have been, actually, the reference to "this mother" that Cernan remembered? Or was "forget the camera" essentially the last meaningful communication humans delivered on the moon?
The best answer, ultimately, may be that we don't know. And that we can't know. Because, despite all the technology we have to connect us to our representatives in space -- as easily as we can talk with them, and tweet with them, and otherwise interact with them -- the fact remains that they are, up there, separate from us. They are, finally, alone. And they alone know what goes on in those little bits of Earth that we send away, hoping they will return.