Spacelog Apollo 8

Go ahead, Houston.

Boresight star is earth, down 037, right 22, plus 10 68, minus 165 00 128 56 361 18 098:27:17. The GDC alignment stars: the primary star is Sirius, secondary Rigel 010, 294, 320, no ullage, path return P37 DELTA-V, 8750. This goes to the Indian Ocean and requires a high-speed procedure, that is minus Mike Alfa, and that will refer to your checklist page November Charlie 1. Over.

Okay, Houston. How do you read?

Loud and clear.

TLI plus 44, SPS/G&N 62970, minus 162, plus 129 046:56:04.31, plus 00197, plus all zeros, plus 60701 180 133 001, plus 00203, plus 60701 704 60451 12 1375 349; earth, down 037, right 2.2, plus 1068, minus 165 12856 36118 098:27:17; Sirius and Rigel. Hello, Houston. How do you read now?

Loud and clear.

Sirius and Rigel, 010 294 320, no ullage, path return P37 DELTA-V 8750, Indian Ocean minus MA, checklist NC 1.

That's affirmative, Apollo 8. And I have a flyby PAD for you, also.

Go ahead.

Okay, Houston. The second flyby SPS/G&N. Are you with me?

Yes sir.

62970, minus 162, plus 129 060:59:48.07, plus 00966, plus 00552, minus 02079. Next three are all zeros, NA, plus 00202 02358 022 02281 03 0407 317 013, up 04.7, right 3.9, plus 1418, minus 16505, plus 12904, plus 36160 146:29:12. Sirius, Rigel, 136 310 340, none, requires realignment to preferred REFSMMAT. Pericynthian to 550 miles.

That's correct, Apollo 8.

Houston, Apollo 8.

Go ahead, Apollo 8.

Okay. When you pick up your activities, I have a preferred alignment here that I want you to be in when you do your P52, and I'll have about four items to change on your time lines, so if you give me a call when you're ready for it.

We're ready right now. We were doing the P52. You want to hold off and go to a particular alignment, is that right?

Affirmative.

All right. I'm ready.

Okay. The attitude is pitch 23.4, roll 184.7, yaw 14.3. And the reason we're doing the alignment in this attitude is, the next thing we'll be coming up with is the scanning telescope visibility test and that will be 70 degrees sun and Arcturus with a shaft and trunnion of zero. and then we can go ahead with the P52 and then a trunnion bias followed by P23 with the same stars we read to you before.

Houston, Apollo 8. We're maneuvering to the angles you—you gave us.

Houston, we've reached the preferred attitude, and we're proceeding with the P52.

Okay. Real fine, and I'll pass up some advice from your friendly flight surgeon. He says you're supposed to take one more Lomotil.

Okay. Everybody, or just me?

Just Frank.

Houston, the P52 is completed. We're ready for your other data.

Okay. Understand that you've done the P52. The next item on the flight plan should be a scanning telescope visibility test, and this is the same one that was on your flight plan previously at 34 hours and about 12 minutes, and we'll be checking that 70 degree sun's on Arcturus. Following that, we need to make a trunnion bias check, and then we'll go into a P23, and I can read you those star numbers and sets if you don't have them from the last time I read them up.

Okay. Standby.

Houston, Apollo 8.

Go ahead.

Roger. With such good visibility or such good communications, we'll just give you a verbal description without seeing the scanning telescope right now. Your angles for maneuvering to Arcturus were quite good. I've got Arcturus centered in the scanning telescope. At this sun angle, there is a shaft of light directly across the center of the scanning telescope and—band of light. It precludes seeing a lot of stars around us, and although I kept my eye glued to the telescope now for some time, it's very difficult to see any star patterns or anything. I couldn't recognize that with Arcturus unless I—the optics just drove me there. Now because I'm near zero shaft and zero trunnion, I'm getting quite a bit of shaft movement. Everytime the shaft moves, more particles leave the optics, and they're just as bright as the surrounding stars. And they mingle in the stars, and you can't tell star patterns or constellations. With this particular attitude, the shaft of light precludes any identification of constellations or individual stars.

Okay. Copy that. Can you tell us something about the orientation of this band? You mentioned that last night also—that you also had a band about 10 degrees wide that ran across. Is there an orientation that we can tie that to?

I believe so, Ken. This band is parallel to the M-line, and I think it has something to do with the design of the optics where we have that shaft or the rectangular entrance of the optics from the outside. At this particular sun angle, it cuts right across. Now I noticed that both the earth and the sun do this to the scanning telescope. In the sextant, the same light band is there, although it covers the entire sextant's field of view. However, the magnification brings out the stars quite well, and it is possible to mark on it. But the identification of the stars with the scanning telescope makes it very difficult. Now the attitude that I found the optics are best at are the attitudes which give the constellations Canis Major and Orion in the scanning telescope. At this, this particular attitude of the spacecraft, the band is gone; we're at a position whereby the sun is behind us, and I can see quite a few stars. Now yesterday I could also, after getting dark-adapted, see quite a few stars around the constellation Cassiopeia which at first I couldn't. But right now this band precludes you see anything at all except Arcturus which, of course, I know we're aiming at right now.

Okay. Thank you very much.

Ken, what stars did you want to use? Did you want to read them off?

Okay. First star will be 26, and we'll be making two sets of measurements, earth near-horizon using star 26. Then we would like to have one set on star 16, that's 16, using the earth far-horizon. If it turns out that star 26 earth near-horizon is not possible, then we'd like to have star 16 on the earth far-horizon for one set, and star 22 earth far-horizon one set. Over.

You want star 26, earth near-horizon, two sets; star 16, earth far-horizon, one set; and star 22, earth far-horizon, one set.

Okay. That's star 22 only in the event that 26 on the earth's near horizon is not possible? Over.

We won't even do star 22 then unless we can't get 26 on the near horizon.

That's affirmative.