Spacelog Apollo 8

Okay. TLI plus 25, and this will be an SPS/G&N. 63087, minus 162, plus 129 027:56:29.64, minus 001 63, plus 00001, plus 527 59 177 137 001, November Alfa, plus 00201 527 59 623 525 43 14 2347 337 023 up 195 left 17, plus 11 45, minus 165 00 127 80 358 90 074:38:16, north stars 068 097 356, no ullage. For the fast return P37 DELTA-V, 7900 to the Indian ocean. High-speed procedures are not required. Over.

In the beginning, the operation with the S-IVB precluded immediate starting up of our sightings as we had scheduled since we had another evasive maneuver. The dumping of the S-IVB caused a tremendous amount of—of pseudo stars in the area which made an optics calibration practically impossible. The method which we had worked out did not seem to work too well. The method which I finally used was to go into P23, go to Sirius, which was our brightest star, get the shaft and trunnion, and then fly the spacecraft up to Sirius to use that for the optics CAL, which we did at a later time. With regards to light scatter, it appears that at almost any attitude during our passive thermal control, we are receiving light scattering in the scanning telescope. It takes the form mostly of a wide band of light right across the center of the scope about 10 degrees either direction of zero. It is very difficult to see stars in this area. The realignments have been good. I have been able to pick up the star in the sextant to do the alignment, but I was not able to identify the star which we used in such cases as Regor or Menkent in the scanning telescope. The first star sighting which I took of the earth showed a very indistinct horizon. But there did appear to be a very—or somewhat sharp line between what appeared to be the earth's horizon and the atmosphere. The landmark line-of-sight filter appeared to help out this horizon definition. There is a very hazy and indistinct horizon through—between the space and the top of the atmosphere itself, and this is a very difficult one to use. As I said before, at times, looking at the moon with the Sun in the near vicinity, the area around the moon, the space around the moon is not dark, but is a light—appears as a light blue. And this is also the same case as looking into the sextant during alignments with the star—with the sun in somewhat vicinity of the optics. However, I have no difficulty in finding these stars in the sextant. I also had no difficulty in spotting the stars I used, such as Sirius, Procyon, or Canopus against the earth during our star-horizon measurements. I can see all three of those stars against the earth background. I believe it will be very difficult to do a backup GDC alignment using the north set stars, since Navi is not too bright of a star. I was able to spot star constellations in the scanning telescope if they were very bright and well known, such as Cetus and Orion, stars of this nature. I was not able to perceive other constellations. That's about the only comments I have at this time. Over.