|Geology Station 1 at Elbow Crater||Geology Station 2|
MP3 Audio Clip ( 7 min 09 sec ) by David Shaffer
122:28:35 Scott: Okay. Mark. ... roll.
122:28:37 Allen: Dave, we want Steering Forward, Off.
122:28:42 Scott: Oh, yeah, yeah, yeah, yeah, yeah. Okay.
[They are now on checklist pages CDR/LMP-11.]122:28:47 Allen: And, Dave and Jim. As you drive away there, I was a little hasty on my time call (at 122:12:52). Mickey (Mouse)'s big hand was actually over his head, and we're running about 30 minutes down now, but we're still looking good.
122:29:02 Scott: Okay.
[Joe and Dave were of a generation that had Mickey Mouse watches when they were kids. The first Mickey Mouse watch was sold by the Ingersoll Watch Company in June 1933 under licence from the Walt Disney Company.]122:29:05 Irwin: Okay, we're moving out again at about 7 - 8 clicks. Heading 180.
[Dave and Jim had planned to depart Elbow at an EVA elapsed time of 2:06 but are currently at an elapsed time of 2:50.]
122:29:14 Scott: Let's head up to...
122:29:15 Irwin: We want about a 225.
122:29:18 Scott: Yeah.
[Jim is looking at Part B of the EVA-1,2 traverse map, which shows an average heading of 225 between Stations 1 and 2.]122:29:19 Irwin: If we can just find...(Pause) As we drive along, there's several craters 3 to 5 meters in diameter. There's a rather large one out at 1 o'clock to us now. We have a heading of 215. It looks fairly recent; there are a lot of angular blocks on the rim of it.
122:30:04 Allen: Jim, let me interrupt one second here. Can you confirm that your DAC (the 16-mm camera) is stopped?
122:30:14 Irwin: That what is stopped?
122:30:16 Allen: The 16-millimeter camera.
122:30:20 Irwin: Yes; it is stopped.
122:30:21 Allen: Thank you.
122:30:24 Scott: Okay, Joe. We're...Careful. You're on me.
[Jones - "Did he nudge your driving arm?"]122:30:27 Scott: Boy, that's a nice fresh one. There's the...There's the answer to...Gosh. Bump! (Pause) Sure hate to go by that one. Okay.
[Scott - "Yeah. That happened every once in a while, just 'cause it's close quarters and he's busy, reaching for maps and stuff like that. It wasn't a big deal, other than caution."]
122:30:42 Irwin: Okay, if we don't find a better crater, that might be a better one to come by. You know?
122:30:45 Scott: Yeah.
122:30:46 Irwin: Don't find a fresher one?
122:30:47 Scott: Yes, that's the freshest we've seen. It's a great one.
[They are looking for a fresh crater with blocky ejecta, one likely to have dug up Hadley Delta bedrock. However, because they have not begun to climb, if they were to stop here, they might find mare basalt rather than highlands material.]122:30:52 Allen: Approximate size, Dave.
[As indicated in the pre-Flight Site Sketch, for each of the traverses, there are broad target areas where specific sampling sites are to be picked in real-time by the crew. For example, on this first EVA, two stops were planned on the lower slopes of Mt. Hadley Delta but with Station 2 only being loosely defined as being in the western part of the hand drawn ellipse and Station 3 being at the west end. Scan by David Harland.]
122:30:53 Irwin: Oh, I see a...Oh, there's another fresh one over there at about 11 o'clock.
122:30:58 Scott: Okay, it's about 20 (to) 25 meters across, and it looked like it excavated the bedrock; it had a very blocky ejecta blanket and blocky rims, and the ejecta blanket was about halfway out. Blocks on the order of about a foot and a half at the largest. And (some of the blocks are) subangular (that is, the edges and corners are slightly rounded), some quite angular.
[Scott - "Subangular is a little bit rounded but not as sharp as 'angular' which are sharp."]122:31:16 Irwin: Bet there's glass in the bottom of that one.
[Jones - "Corners knocked off a little bit but you can still see planes and protrusions."]
[Scott - "Yeah. Knocked off or worn off, but not really sharp."]
122:31:17 Scott: Yeah, there sure is.
122:31:19 Irwin: Yeah, we're starting a slight upslope now.
122:31:22 Allen: Roger.
122:31:26 Irwin: As we approach the Front. (Pause) And what a beautiful view looking up that slope.
122:31:31 Scott: Isn't that; and you can see the lineaments come down cutting across there can't you? Going from...Let's see; it's got to be northeast to southwest, huh? Okay, let's pick a...Let's just head up the slope here.
122:31:51 Irwin: It would be great if we could get up to that rather large...(Garbled) I think that's too far away, Dave.
122:31:57 Scott: I do, too. (Pause)
[They may be discussing the 50-meter, bright-rimmed crater on the east rim of St. George shown in Dave's SEVA photo AS15-84 11236. However, that crater is well up slope from they're current location and about a kilometer away.]122:32:00 Scott: Man, this is getting...Ho, ho, ho. Look at these here. Deep, subdued, but...
[Scott, from the 1971 Technical Debrief - "I think our (pre-mission) idea of going up to the rim of St. George would not have been worth the time, because there apparently wasn't that much on the rim to tell us anything. There was no ejecta blanket, and there was no distribution of increase in fragmental debris anywhere that I can remember."]
[Irwin, from the 1971 Technical Debrief - "I guess, the only thing that would have been significant would have been if we could have gotten up to that very fresh, light-colored crater."]
[Scott, from the 1971 Technical Debrief - "We considered doing that for a while."]
[Irwin, from the 1971 Technical Debrief - "Yes, you did."]
[Scott, from the 1971 Technical Debrief - "I was going to drive up there, but I think we ran out of time by sampling the block (at Station 2). That would have been a very good crater to sample, because it's quite visible, as I remember, even from orbit."]
[Irwin, from the 1971 Technical Debrief - "Yes, you can see it from orbit. It was a fresh crater, and it was very light albedo. I just wonder if that light material is that very light (color) from the anorthosite. You know, it (light-colored soil?) was underneath the big rock (at Station 2) and it was kind of powdery white."]
[They will tip over the Station 2 boulder at 122:54:35, but there is no discussion of the albedo of the soil that was underneath it.]
[Scott, from a 1996 letter - "There was no visible difference, as I recall. Nothing like the white soil we saw when we disturbed (some) crater rims."]
[Scott, from the 1971 Technical Debrief - "It (meaning the light-colored material on the crater higher up Hadley Delta) could have been (due to anorthosite). Too bad we didn't get up there."]
[Irwin, from the 1971 Technical Debrief - "Too bad we didn't get a lot of places."]
[Scott, from the 1971 Technical Debrief - "Yes."]
122:32:07 Irwin: Deep, but there's not much fresh ejecta around them.
122:32:10 Scott: No. Man, steep slopes; that must be 30 degrees on the side. And a little old crater that couldn't be more than 10 meters across. We're heading for St. George, I think, huh?
122:32:23 Irwin: Yeah. (Pause)
[Scott - "I hadn't really thought about this before but, probably, we're into the deeper regolith now. So, when there's a crater, it's a deeper crater with steeper slopes. 'Cause it's not as firm a surface."]122:32:27 Irwin: Now, there are some blocks now that look like they're a foot (across). Angular blocks. Seems like they're on the surface, Dave. Look over there at 11:30...Just about 11:30.
[Jones - "And without blocks around them because all you're digging up is regolith. And do I interpret this 'We're heading for St. George, huh?' as meaning you're on the slope now and you can't actually see St. George anymore?"]
[Scott - "I don't remember, but that may be right."]
[Jones - "We were talking this morning that, back at the LM, you could see into St. George, but here..."]
[Scott - "You're too close, you probably can't. Probably not. It would be interesting to look at the pan that Jim took at the last stop and see what, from Station 1, we could see of St. George. That's why it would probably take years, to go back and review this, because you get into these kind of details."]
[We then looked through pictures and decided that, as shown in AS15-85- 11413, they could see into St. George a little bit from Station 1.]
[Jones - "As you got closer, you would have lost it."]
[Scott - "Here's Station 2, and you really can't see St. George anymore. Never looked at these pans, before. Gee, they did a good job of pasting them together."]
[Jones - "That's a tricky business. I've tried doing it myself."]
122:32:40 Scott: Yeah, they are. Most of them have been buried at this time, and those seem like they're right on the...
122:32:43 Irwin: Yeah, they're right on the surface for some reason.
[A large ejecta fragment from an impact will tend to dig a hole where it lands and the steady rain of small impactors on the surrounding surface will fill in the gaps around the boulder and partially bury it. Later impacts will splash soil on the sides of the rock and the soil will fall to the surface at the base of the rock, building up a skirt of dirt called a fillet. And finally, a large nearby impact may overturn all of the material in the area and completely bury what were partially buried rocks. Filletless blocks sitting on the surface are of two types: (1), they have only been at their current locations for a short period of time; or (2), near the edge of the rille, they may be sitting on only a shallow layer of regolith.]122:32:46 Scott: Oh, that antenna (possibly the low gain, even though the comm does not seem to have degraded) fell down. (Pause) Okay, Joe, we're going uphill pretty good. We're just...
122:32:56 Allen: Roger, Dave. Copy. Your updated range at station 2 is about 3.9 clicks (kilometers). And if you'll park down-Sun, we'll give you a Nav update when you climb back on.
122:33:10 Scott: All righty.
[Using the Nav readouts at Elbow, Houston has revised their estimate of the LM location. Had they landed at the planned spot, Station 2 would have been 3.4 kilometers from the LM.]122:33:12 Irwin: Hey, we're reading 3.8 right now...
122:33:13 Allen: Must be getting close.
122:33:14 Irwin: ...4.4; okay.
122:33:15 Scott: (Lost under Joe) don't ya.
122:33:16 Irwin: The light-colored one out there?
122:33:18 Scott: Yes, sir.
[Here, they are almost certainly talking about the 50-m bright rimmed crater on the east rim of St. George.]122:33:19 Irwin: That'd be a good one.
122:33:21 Scott: But it looks awful rough up there, doesn't it?
122:33:24 Irwin: Yeah, and it's probably farther away, Dave, than we could go.
122:33:27 Scott: Yeah, we'll just keep mushing along here.
122:33:30 Irwin: There's a large block - looks like about a 5-footer - out at 1 o'clock. Angular block.
122:33:35 Scott: Yeah, you're right. Why don't we go there? You can tell we're going uphill.
122:33:43 Irwin: Yeah, speed's dropped down to 7 clicks. (Pause) Yeah, if we just go straight over to that big one.
122:33:51 Scott: Yeah, that's what we'll do.
122:33:53 Allen: Sounds good to us. Any place that looks good to the two of you.
122:33:56 Irwin: ...to a big boulder.
122:33:57 Scott: Well, it looks fairly...(Responding to Joe) Okay; we're going to a big block here, Joe. It's one we just can't afford to miss. Wanted us to look at a big block; we're going to look at a big block. It's the only big block I see anywhere.
122:34:11 Irwin: Yeah. (Light static)
[Because they are now driving upslope, the low-gain antenna is pointed more toward the north and the Earth may be getting near the edge of the main lobe of the antenna pattern. The antenna has to be pointed within about 30 degrees of Earth for good comm.]122:34:12 Scott: Hey, we could get to that fresh one, too, Jim. Hang on. Hang on. Digging in. (Pause) Okay. Boy, this'll give them a view. Oh my!
122:34:33 Irwin: Yeah, look that...What a view back into the rille.
122:34:35 Scott: Ohhh! There's almost a view right into that crater.
122:34:40 Irwin: Glad you stopped short of it.
122:34:41 Scott: (Laughs)
122:34:42 Irwin: Let's stop here.
122:34:43 Scott: Huh?
122:34:44 Irwin: Let's stop here?
122:34:45 Scott: I got to go down-Sun just a minute. I want to back up just a tad. (Pause) Okay; as far as we can...(Pause)
122:34:55 Allen: And, Jim, as you look back, can you see the Rover tracks?
122:35:02 Irwin: Oh, standby...
122:35:04 Scott: Yeah, we could, Joe. I saw them when we stopped at the last stop.
122:35:08 Allen: Okay; good. (Pause) Sounds like the old Hansel and Gretel trick'll work.
122:35:16 Scott: Yeah, man. (Pause) Okay. We're there, Jim; you can get off. You can try and get off. (Pause)
122:35:27 Irwin: Made it.
|Geology Station 1 at Elbow Crater||Apollo 15 Journal||Geology Station 2|