When I write out this clue, I am most likely writing it differently from how I created it. I write it from the perspective of figuring it out.
In other words, it appears that I start at the end and work my way back.
To create it, I start with two fixed values and then determine that end point of 11/21/1983.
I started with 7/16/1963, 12/23/1968, and 6/7/1976 and used that to produce 11/21/1983.
From 7/16/1963 to 6/7/1976 is: 4710 days
From 6/7/1976 to 11/21/1983 is: 2723 days
4710 - 2723 = 1987
From 7/16/1963 to 12/23/1968 is: 1987 days
It is also interesting to note that while 12/23/1968 was a Monday, I think it was actually Tuesday when Apollo 8 entered orbit of the Moon. I haven't fully examined the details to determine whether that is correct yet, though. But since I have been looking at it, in the context of the song, I have been thinking of it in the sense of anticipation, which means on Monday, 12/23/1968, the was a great sense of anticipation about being the first humans to orbit the Moon. It could be that we did enter orbit on Monday, perhaps in some Earth time-zone, or it just be that I think of the anticipation on that Monday, of entering orbit of the Moon on 12/24/1968. I've read that Apollo 8 was in orbit for 20 hours and during the day of Tuesday, 12/24/1968, but I haven't determined when orbit was achieved.
I wonder if this is the source of that memory of a child named Charlie Brown who was smearing crap from his diaper onto the refrigerator. That was when Thedia was married to James Nevells and he was in the Marines. I was over at the house of one of his fellow soldiers and Charlie Brown was his kid. I pointed out to the wife that Charlie was smearing poop on the fridge. I can still visualize that. I can also visualize watching "Speed Racer" on their television. I think that kid also crapped in his father's uniform shoe.
There is also something familar about that sense of jolting awake as I wonder why I have similar artificial memories from long ago.
http://en.wikipedia.org/wiki/Apollo_8
...
Eleven hours into the flight, the crew had been awake for over 16 hours, having been awakened about 5 hours before launch. So it was time for Frank Borman to start his scheduled 7-hour sleep period. It proved difficult to sleep. NASA had decided that at least one crewmember should be awake at all times to deal with any issues that might arise. But the constant radio chatter with the ground and the air circulation fans made it hard to sleep. As well as this, sleeping in space is a somewhat unnatural experience—you cannot rest your head on a pillow and Bill Anders said that he would suddenly jolt awake with the sensation that he was falling.
About an hour after starting his sleep period, Borman requested clearance to take a Seconal sleeping pill, but the pill had little effect. After Borman slept for seven hours fitfully, he awoke feeling ill. He vomited twice, and had a bout of diarrhea that left the spacecraft full of small globules of vomit and feces. The crew cleaned up as best as they could. Borman decided that he did not want the world to know about his medical problems but Lovell and Anders still wanted to tell the ground. They decided to use the Data Storage Equipment (DSE), which could be used by the crew to tape voice recordings and telemetry, which were then dumped to the ground at high speed. After recording a description of Borman's illness they requested that mission control check the recording, as the crew "would like an evaluation of the voice comments".
I probably started with how Apollo 17 landed on the moon on Monday and then 6/7/1976 was a Monday. That was probably scheduled for that detail because Monday is based on "moon day."
So then I knew that Phoebe was 1987 days old on Monday, 12/23/1968 and then 4710 days on Monday, 6/7/1976. I subtracted 1987 from 4710 which gave me 2723.
Then I looked forward 2723 days from 6/7/1976, which gave me 11/21/1983.
So the date for Apollo 17 didn't actually figure in. I just knew that it was a Monday and that it was the last lunar landing. That was probably scheduled for a Monday for that reason. And then I scheduled the Phoebe/Saturn landing for the same reason and because it was the first new moon I would land on. I had been to Mars before Phoebe/Saturn, but that is a planet. Phoebe was the first new moon that a human had been to. As with the last landing on Luna was a Monday, the first landing on the new moon, Phoebe/Saturn, would be a Monday, too. I also think that is the basis for the Foreigner lyrics about the "sad Monday." I landed on Phoebe/Saturn on that Monday and I was probably going to successfully launch from there to Jupiter on 6/9/1976, but at the time of the Phoebe/Saturn landing, it wasn't expected that I was going to make it back to Earth alive because I didn't have enough oxygen for the full trip.
Maybe it was still Monday, 12/23/1968, in Hawaii when Apollo 8 entered orbit of the Moon.
The article indicates that Apollo 8 launched at 1251 UTC on 12/21/1968 and it looks like it entered orbit around 68 hours later, although I need to concentrate harder on that.
http://www.timeanddate.com/worldclock/city.html?n=103
Honolulu, Hawaii, U.S.A.
Honolulu is capital of the state Hawaii
Honolulu is on the Oahu island
Current time Tuesday, June 5, 2007 at 10:23:53 PM
UTC/GMT Offset Standard time zone: UTC/GMT -10 hours
Current UTC (or GMT/Zulu)-time used: Wednesday, June 6, 2007 at 08:25:24
UTC is Coordinated Universal Time, GMT is Greenwich Mean Time.
So it looks to me that Apollo 8 launched at 0251 Hawaii time on Saturday, 12/21/1968.
If it entered orbit 68 hours later then:
48 hours after launch would be 0251 on Monday, 12/23/1968.
20 hours after that, for a total of 68 hours, would be 2251, Monday, 12/23/1968.
So 58 minutes after that would be 2349, Monday, 12/23/1968, Hawaii-time, when Apollo 8 went behind the Moon.
http://en.wikipedia.org/wiki/Apollo_8
...
At 64 hours into the flight, the crew began to prepare for Lunar Orbit Insertion-1 (LOI-1). This maneuver had to be performed perfectly, and due to orbital mechanics had to be on the far side of the Moon, out of contact with the Earth. After Mission Control was polled for a Go/No Go decision, the crew was told at 68 hours, they were Go and "riding the best bird we can find". At 68 hours and 58 minutes, the spacecraft went behind the Moon and out of radio contact with the Earth.
http://www.onlineconversion.com/days_between_advanced.htm
First date and time 12/21/1968 02:51:00
Second date and time 12/23/1968 23:49:00
Result 2 days, 20 hours, 58 minutes
Or: 68 hours, 58 minutes