Phase 4: Lunar Orbit

Bruce McCandless (CAPCOM)

Apollo 11, Apollo 11, this is Houston. Do you read? Over.

Bruce McCandless (CAPCOM)

Apollo 11, Apollo 11, this is Houston. Do you read? Over.

Unidentified crew member

Unidentified crew member

Houston, Apollo 11. Over.

Bruce McCandless (CAPCOM)

Apollo 11, Apollo 11, this is Houston. We are reading you weakly. Go ahead. Over.

Neil Armstrong (CDR)

Roger. Burn status report follows. DELTA-TIG zero, burn time 557, … VGX minus O.1, VGY minus 0.1, VGZ plus 0.1, DELTA-VC minus 0.390, fuel, plus 3 … 42. Over.

Bruce McCandless (CAPCOM)

11, this is Houston. These residuals, do you have minus 0.1?

Unidentified crew member

… VGX minus 0.1, VGY minus 0.1, VGZ 1.1, and a burn time of 5 plus 57. Stand by, maybe the COMM will improve a little bit. Over.

Bruce McCandless (CAPCOM)

Apollo 11, this is Houston. Are you in the process of acquiring data on the burn? Over.

Bruce McCandless (CAPCOM)

Apollo 11, Apollo 11, this is Houston. How do you read?

Neil Armstrong (CDR)

Reading you loud and clear, Houston. How us?

Bruce McCandless (CAPCOM)

Roger. Reading you the same, now. Could you repeat your burn status report? We copied the residuals and burn time, and that was about it. Send the whole thing again, please.

Neil Armstrong (CDR)

It was like—like perfect! DELTA-TIG zero, burn time 557, shaft value on the angles, VGX minus 0.1, VGY minus 0.1, VGZ plus 0.1, no trim, minus 6.8 on DELTA-VC, fuel was 38.8, LOX 39.0, plus 50 on balance, and we ran an increase on the PUGS, NOUN 44 showed us in a 60.9 by 169.9.

Bruce McCandless (CAPCOM)

Roger. We copy your burn status report. And the spacecraft is looking good to us on telemetry.

Neil Armstrong (CDR)

Everything looks good up here.

Neil Armstrong (CDR)

Apollo 11 is getting its first view of the landing approach. This time we are going over the Taruntius crater, and the pictures and maps brought back by Apollo 8 and 10 have given us a very good preview of what to look at here. It looks very much like the pictures, but like the difference between watching a real football game and watching it on TV. There's no substitute for actually being here.

Bruce McCandless (CAPCOM)

Roger. We concur, and we surely wish we could see it firsthand, also.

Buzz Aldrin (LMP)

We're going over the Messier series of craters right at the time, looking vertically down on them, and Messier A we can see good sized blocks in the bottom of the crater. I don't know what our altitude is now, but in any case, those are pretty good size blocks.

Bruce McCandless (CAPCOM)

Okay. Just roughly, it looks like you are about 120 miles or 130 miles right now—make that 127 miles.

Neil Armstrong (CDR)

We're approaching PDI point now. Over.

Neil Armstrong (CDR)

There's Secchi in sight.

Buzz Aldrin (LMP)

We're going over Mount Marilyn at the present time, and it's ignition point.

Bruce McCandless (CAPCOM)

Roger. Thank you. And our preliminary tracking data for the first few minutes shows you in a 61.6 by 169.5 orbit. Over.

Bruce McCandless (CAPCOM)

Apollo 11, this is Houston. Over.

Bruce McCandless (CAPCOM)

11, Houston. During your SPS burn as played back on tape down here, we've observed the nitrogen tank Bravo pressure in the SPS system dropping a little bit more than we anticipated. It's holding steady right now. We'll continue to watch it and keep you posted if anything comes up. Over.

Bruce McCandless (CAPCOM)

Right. And it has held steady —

Neil Armstrong (CDR)

Currently going over Maskelyne Mas -

Neil Armstrong (CDR)

And Boothill, Duke Island, Sidewinder, looking at Maskelyne W, that's the yaw round checkpoint, and just coming into the terminator. At the terminator it's ashen and gray. As you get further away from the terminator, it gets to be a lighter gray, and as you get closer to the subsolar point, you can definitely see browns and tans on the ground, according to the last Apollo 11 observation anyway.

Bruce McCandless (CAPCOM)

Roger, 11. We're recording your comments for posterity.

Michael Collins (CMP)

Did somebody in the background—do they accuse us of being compromisers? Huh!

Neil Armstrong (CDR)

And landing site is well into the dark here. I don't think we're going to be able to see anything of the landing site this early.

Bruce McCandless (CAPCOM)

Apollo 11, this is Houston. When you have a free minute, could you give us your onboard readout of N2 tank Bravo, please. And we'd like to make sure you understand that ever since you stopped thrusting with the SPS, the temperature in this tank has remained steady. Over. Make that the pressure has remained steady.

Michael Collins (CMP)

Roger. We understand tank pressure has stayed steady. Thank you.

Buzz Aldrin (LMP)

Roger. We're showing the N2 tank pressure and the tank Bravo to he 1960, something like that, and Alfa is, oh, about 2250. Over.

Bruce McCandless (CAPCOM)

Roger. We show 2249 in Alfa and 1946 down here.

Michael Collins (CMP)

Houston, Apollo 11. How about coming up with some roll, pitch, and yaw angles in which to stop this so called ORB RATE that I'm doing.

Bruce McCandless (CAPCOM)

We'll have them for you in a minute, 11.

Michael Collins (CMP)

Okay. And time to stop also, please.

Bruce McCandless (CAPCOM)

Apollo 11, this is Houston. Over.

Bruce McCandless (CAPCOM)

Roger. We show you, in the flight plan, staying in orbital rate until about 79 hours 10 minutes. Do you have some particular attitude or reason for wanting to go inertial? Over.

Expand selection up Contract selection down Close
Buzz Aldrin (LMP)

No, that's fine. I just wanted to confirm that. Until 79 10, then we'll breeze around here in orbit.

Expand selection down Contract selection up

Spoken on July 19, 1969, 6:28 p.m. UTC (50 years, 1 month ago). Link to this transcript range is: Tweet

Bruce McCandless (CAPCOM)

Roger. And we've got an observation you can make if you have some time up there. There's been some lunar transient events reported in the vicinity of Aristarchus. Over.

Buzz Aldrin (LMP)

Roger. We just went into spacecraft darkness. Until then, why, we couldn't see a thing down below us. But now, with earthshine, the visibility is pretty fair. Looking back behind me, now, I can see the corona from where the Sun has just set. And we'll get out the map and see what we can find around Aristarchus

Neil Armstrong (CDR)

We're coming upon Aristarchus right now —

Bruce McCandless (CAPCOM)

— Okay. Aristarchus is at angle Echo 9 on your ATO chart. It's about 394 miles north of track. However, at your present altitude, which is about 167 nautical miles, it ought to be over—that is within view of your horizon: 23 degrees north, 47 west. Take a look and see if you see anything worth noting up there. Over.

Buzz Aldrin (LMP)

Houston, 11. It might help us a little bit if you could give us a time of crossing of 45 west.

Buzz Aldrin (LMP)

You might give us a time of crossing of 45 west, and then we'll know when to start searching for Aristarchus.

Bruce McCandless (CAPCOM)

Roger. You'll be crossing 45 west at 77 04 10 or about 40 seconds from now. Over. Thirty seconds from now.

Bruce McCandless (CAPCOM)

Apollo 11, when we lose the S-band, we'd like to get OMNI Charlie from you. And update my last, that 77 04 was the time when Aristarchus should become visible over your horizon. 77 12 is point of closest approach south of it. Over.

Buzz Aldrin (LMP)

Okay. That sounds better because we just went by Copernicus a little bit ago.

Bruce McCandless (CAPCOM)

Roger. We show you at about 27 degrees longitude right now.

Buzz Aldrin (LMP)

Houston, when a star sets up here, there's no doubt about it. One instant it's there, and the next instant it's just completely gone.

Bruce McCandless (CAPCOM)

Apollo 11, this is Houston. We request you use OMNI Charlie at this time. Over.

Buzz Aldrin (LMP)

Okay. Going to OMNI Charlie.

Bruce McCandless (CAPCOM)

Apollo 11, this is Houston. Go ahead.

Buzz Aldrin (LMP)

Roger. Seems to me since we know orbits so precisely, and know where the stars are so precisely, and the time of setting of a star or a planet to so very fine a degree, that this might be a pretty good means of measuring the altitude of the horizon …

Michael Collins (CMP)

Hey, Houston. I'm looking north up toward Aristarchus now, and I can't really tell at that distance whether I am really looking at Aristarchus, but there's an area that is considerably more illuminated than the surrounding area. It just has—seems to have a slight amount of fluorescence to it. A crater can be seen, and the area around the crater is quite bright.

Buzz Aldrin (LMP)

Houston, Apollo 11. Looking up at the same area now and it does seem to be reflecting some of the earthshine. I'm not sure whether it was worked out to be about zero phase to—Well, at least there is one wall of the crater that seems to be more illuminated than the others, and that one—if we are lining up with the Earth correctly, does seem to put it about at zero phase. That area is definitely lighter than anything else that I could see out this window. I am not sure that I am really identifying any phosphorescence, but that definitely is lighter than anything else in the neighborhood.

Bruce McCandless (CAPCOM)

11, this is Houston. Can you discern any difference in color of the illumination, and is that an inner or an outer wall from the crater? Over.

Michael Collins (CMP)

Roger. That's an inner wall of the crater.

Buzz Aldrin (LMP)

No, there doesn't appear to be any color involved in it, Bruce.

Bruce McCandless (CAPCOM)

Roger. You said inner wall. Would that be the inner edge of the northern surface?

Michael Collins (CMP)

I guess it would be the inner edge of the westnorthwest part, the part that would be more nearly normal if you were looking at it from the Earth.

Bruce McCandless (CAPCOM)

11, Houston. Have you used the monocular on this? Over.

Buzz Aldrin (LMP)

Roger. Like you to know this quest for science has caused me to lose my E memory program, it's in here somewhere, but I can't find it.

Bruce McCandless (CAPCOM)

11, this is Houston. We're—we're hearing only a partial COMM. Say again please.

Neil Armstrong (CDR)

Houston, we will give it a try if we have the opportunity on next—when we are not in the middle of lunch, and trying to find the monocular.

Bruce McCandless (CAPCOM)

Roger. Copied you that time. Expect in the next REV you will probably be getting ready for LOI 2.

Bruce McCandless (CAPCOM)

So, let's wind this up, and since we've got some other things to talk to you about in a few minutes. Over.

Bruce McCandless (CAPCOM)

Apollo 11, this is Houston. Over.

Bruce McCandless (CAPCOM)

11, this is Houston. We're targeting—planning to make the LOI 2 burn now using bank A only. We'll have the PAD and everything for you next time around. Just trying to economise a little on bank B. Bank B is holding, though.

Bruce McCandless (CAPCOM)

Apollo 11, this is Houston. Over.

Bruce McCandless (CAPCOM)

11, Houston. In order to improve the communications a little bit here, we'd like to try to get you on the high gain antenna. We're recommending a pitch angle of 0, yaw 355—I say again 355, the track switch to MANUAL, and wide beamwidth. Over.

Neil Armstrong (CDR)

Okay. You ready to switch to high gain now?