Irwin's Dunes

Hadley Rille

 

Instant Rock at Station 9

Corrected Transcript and Commentary Copyright © 1996 by Eric M. Jones.
All rights reserved.
Scan credits in the Image Library
Last revised 9 October 2014.

MP3 Audio Clip ( 10 min 47 sec ) by David Shaffer

165:01:55 Scott: I'll get it (probably meaning Jim's seatbelt) for you if you want.

165:01:59 Irwin: (To Joe) And the readings, (heading) 267, (bearing) 088, (distance driven) 2.2, (range) 1.6, 90, 92, 100, 108, and motor temps are still (off-scale) low.

165:02:22 Allen: Roger. (Static)

[These readouts indicate a position of about BS.4/66.6. According to the Apollo 15 Preliminary Science Report ( 51 Mb ). They have parked on the rim of a crater 15 meters in diameter about 75 meters south of the rim of Scarp Crater. That would put them close to BR.8/66.9 and gives credence to Dave's observation 166:38:34 during the drive back to the LM at that the Nav system was "biased right" by about 8 degrees. If we subtract 8 degrees from the bearing, the implied position is BR.5/66.7, in good agreement with their actual location.] [When an LROC image of the site was taken on 30 October 2009, the Sun's elevation of 51.5 degrees was high enough to show that the Station 9 crater is very fresh, surrounded by a bright ejecta blanket. Scarp Crater does not show up well at this high Sun angle; but it shows up well in a labeled detail from an LROC image taken on 13 July 2009, with the Sun low in the West.]

{A second detail from the October image has been combined with the planmetric station map from the Preliminary Science Report ( 51 Mb ) to show the LRV parking spot and the places where Dave and Jim will collect samples and take a pan. The planimetric map has been scaled to match size of the drawn crater to the actual crater.]

[Post-mission analysis suggests that this site is on a local topographic high formed by the merger of the ejecta blankets of Scarp Crater and the unnamed feature they just drove through SE of Scarp. Consequently, the regolith is probably quite thick here and, as a result, the impact that dug the Station 9 crater did not reach bedrock. Consequently, most of the ejecta are piece of regolith breccia (soil compacted in the impact). The Apollo 17 crew sampled very similar material at Van Serg Crater which, coincidentally, was their Station 9 as well.]

165:02:31 Irwin: I'm going to see if I can fix my (Hasselblad) camera.

165:02:34 Allen: Good idea, Jim. And Dave...

165:02:36 Scott: Which way is...

165:02:37 Allen: ...if our TV camera's still tilted down. Could you fix it for us, please?

165:02:42 Scott: Rog. There you go; it's up. I'll try and get you on the AGC. You ought to be there. (Pause) AGC looks good.

Video Clip  3 min 18 sec ( 0.8 Mb RealVideo or 29 Mb MPG )

165:02:51 Allen: Okay. Thank you, Dave. And a word on that (TV) camera. We'll position it before the two of you start the move, and just leave it in whatever position we put it in.

[TV on. We have a view of the left flank of Mt. Hadley past the bottom of Jim's PLSS.]

[Fendell pans right and gets a view of Jim working on his Hasselblad.]

165:03:23 Scott: Document the thing here.

165:03:24 Allen: ...an EMU status check, please?

[Sometimes, a request for an "EMU status check" is, in fact a request that the crew slow down and take a breather. Here, it is a real request because Dave and Jim have just gotten off the Rover after a restful drive. As indicated in Figure 10-5 from the Mission Report, Dave's heart rate dropped into the mid-60's during the drive and Jim's dropped to about 80. Neither of them will reach particularly high heart rates during this EVA.]

165:03:39 Allen: Sounds good.

[Fendell has started a counter-clockwise pan. There is enough dust on the lens to produce noticeable, if not severe, degradation of the picture. Houston will ask Dave to dust the lens once they get to Station 9a at the edge of the rille.]

165:04:00 Allen: And, Jim...

165:04:01 Scott: Okay, (garbled)

165:04:02 Irwin: Yeah.

165:04:03 Allen: ...do you want some help on that 70-millimeter camera mal(function)-procedures?

165:04:09 Irwin: Well, I'm holding the trigger depressed and advancing the film, manually, to see if it'll...

165:04:15 Allen: That's right on.

165:04:16 Irwin: ...kick over. But it's not. I guess it's not working. I guess, the only thing I could do at this point is change the mag.

165:04:26 Allen: Jim, before you do that, try rotating the lens in front. It may be hung up between detents.

165:04:38 Irwin: Okay, I'll try that. You mean the locking device on the lens itself?

165:04:42 Allen: That's right.

165:04:49 Irwin: No, it's locked. (Pause) Dave, you want to take the time here to let me change the mag?

165:05:01 Scott: Yeah, why don't you try it, Jim?

165:05:02 Irwin: Okay, I'll try it...

165:05:03 Allen: Sounds good to us, Jim.

165:05:04 Irwin: ...it's the only thing to be done.

[The planned Station 9 tasks are listed on CDR-27 but are more appropriate to a stop at the edge of the rille.]

165:05:06 Irwin: Okay.

165:05:07 Scott: ...I'll get a pan from the rim of Scarp. And the rim is very, very soft. My boot sinks in a good - if I push on it - a good 4 inches. And the whole center part of the crater is just full of debris. Very angular, glass in the center. It's about, oh, I guess, 40 meters across and maybe 5 or 6 meters...No, not that much. 3 or 4 meters deep. And a slightly-raised rim. An ejecta blanket that goes out about one crater diameter, quite uniform. I don't see any rays. There are slickensides on some of the fragments. And we'll get to sampling them in a second here.

Video Clip  3 min 03 sec ( 0.8 Mb RealVideo or 27 Mb MPG )

165:06:04 Allen: Roger. (Long Pause)

[Fendell reaches the counter-clockwise pan limit. Jim is at Dave's seat changing film magazines. The crater - which is not actually Scarp Crater - is behind the Rover. As Dave indicated to Houston, he wasn't thinking about TV when he parked and, in fact, picked the worst possible orientation for coverage of their activities at the crater. They will be out of view - hidden by the seats - virtually the whole time they are at this station.]

[Fendell reverses direction.]

[Dave's pan (assembled by Dave Byrne) consists of frames AS15-82- 11066 to 11092.]

[Dave began the pan with a down-Sun picture, 11066. He is standing on the north rim of a 15-m diameter crater.]

[Frame 11067 is centered on Hill 305 and shows the blocky ejecta surrounding this very fresh crater. As at Apollo 17's Van Serg Crater, the ejecta here is almost all blocks of regolith (soil) compressed in the impact that dug the crater. The formal term for this compressed material is "regolith breccia". The informal term is "instant rock."]

[Frame 11069 shows the inbound Rover tracks just below center.]

[Frame 11078 shows the northeastern rim of the Station 9 crater.]

[Frame 11082 shows the bench on the eastern wall. Dave describes the bench at 165:07:51.]

[Frame 11085 shows the view across the middle of the crater toward Hadley Delta.]

[Frame 11087 is centered on St. George Crater.]

[At the right edge of frame 11090, we see Jim at the Rover.]

[Frame 11091 is centered on Jim. For reference, the Rover is pointed away from us, almost due west.]

[Frame 11092 ends the pan.]

165:06:46 Irwin: Yeah, you have; just right. Okay, I'm trying it. (Long Pause) Yeah, I think the camera's working, Joe. I'm going to put mag Romeo on.

165:07:12 Allen: Sounds good.

165:07:13 Scott: That mag worked for a while this morning, didn't it, Jim?

165:07:15 Irwin: Yeah. (Long Pause) Camera's got so much dust on it, I... (Pause)

[Fendell examines the eastern flank of Hill 305 at maximum zoom and then reverses direction.]

[Since finishing the pan, Dave may have taken a cross-Sun stereopair of a sample at the crater rim. These are AS15-82- 11093 and 11094.]

[Normally, a bench would indicate the depth of the regolith but, here, because of the absence of basalt ejecta and the predominance of regolith breccia suggest that, in this case, there is some other cause of the bench.]

[Dave took three pictures of the bench, AS15-82- 11095 to 11097.]

165:08:13 Scott: Okay, I'm going to get a couple of samples from the rim here; on the surface. (Pause) Oop; the first one I tried to pick up, just fell apart (which is a good sign of regolith breccia). Get a couple pieces of it. Won't be able to look at it for you, but I'll bring it home. It's a clod; it's just a caked clod. And it's in 273.

165:08:42 Irwin: I'll come over there, Dave. I put on the other mag; it doesn't work. I think the shutter's working on the camera, but the drive is not.

165:08:48 Scott: It was working fine last night.

[Fendell reaches the counter-clockwise pan limit.]

165:08:55 Scott: Okay. This stuff is really soft; (bag 2)73.

Video Clip  2 min 27 sec ( 0.6 Mb RealVideo or 22 Mb MPG )

165:09:04 Allen: Roger. (Long Pause)

[Jim goes around the back of the Rover to his seat. The TV image jiggles, possibly as Jim raises his seat to stow his camera. Fendell starts a clockwise pan.]

[Dave has taken another stereopair of cross-Sun "befores" of a sample, AS15-82- 11098 and 11099, and then an "after", 11100.]

165:09:30 Scott: No, I can do it just as well. Look at that, there's slickensides on that one. (Pause) Okay. Get some on the rim. Trying...

[Dave takes two "befores" of the "slickensides" rock, AS15-82- 11101 and 11102. A slickensides is a smooth surface created when two rock faces slide across each other.]

165:09:53 Scott: Yeah, you're right.

165:09:55 Irwin: Very soft on the rim.

165:09:56 Scott: Isn't it, though? (Long Pause)

[At some point, possibly here, Dave turned the "slickensides" rock and took AS15-82- 11103 and 11104.]

165:10:14 Scott: These look like big pieces of mud, don't they? (Pause) Okay, let's take a couple of steps out the rim here. I got one on the rim.

165:10:25 Irwin: You did get the sample already?

165:10:27 Scott: Yeah. Let's go down here, you know, a ways out in the ejecta, and see if we can get a couple more. Here's a nice big one. It's too big for the bag. (Pause) There's (garbled) sparklies in it, Jim. Think we can get that in the bag? I'll try.

[Fendell reaches the clockwise pan limit without finding Dave and Jim. They are hidden by the seats and the geopallet. In the distance beyond and just to the left of Jim's seat, we see a considerable amount of blocky ejecta at the crater rim and, in the far distance, the Swann Range with some outcrops evident on the mountain side just south of the southern flank of Mt. Hadley. Fendell zooms in on the mountains. Dave's photo AS15-82- 11078 shows the area in question as seen from the north rim of the crater.]

[While Jim gets a sample bag ready, Dave takes a stereopair of cross-Sun "befores" of the "nice big one", AS15-82- 11105 and 11106. Note Jim's shadow across the top of the pictures. Figure 5-113 from the Apollo 15 Preliminary Science Report is a pre-sample sketch map based on 11105. the sample is 15505, an 1147-gram regolith breccia. Another, slightly larger sample is 15558, a 1333-gram regolith breccia with similarities to 15505, also may have been collected at Station 9.]

[ Dave then took a down-Sun, 11107 and, finally, raised his aim to take 11108, a "locator" to the Rover. Bennett Hill is in the background and, at the left side of the picture, we can see Jim's left hand and the sample bag.]

165:11:06 Scott: That's right. Well, not every fragment. Many of these clods don't have any at all. Most of them don't have any glass. (To himself) (I'll) get that one there. (Pause)

[Jim's observation that the Station 9 crater resembles the small craters with glass in the bottom and bits of regolith breccia in the ejecta - called Glass-lined, Pit-bottomed craters, or GLPBCs, by the Apollo 17 crew - is probably right on target. It is a first-rate observation.]

[Scott, from the 1971 Technical Debrief, "The frags that we picked up there were clods. I mean they fell apart - were very fragile."]

[Irwin, from the 1971 Technical Debrief, "They all looked the same, sort of angular, but they did have some glass in them. I guess we disagree there, for I say that crater is similar in characteristics to the very small ones that we saw earlier, except there is no concentration of glass in the very center."]

[Scott, from the 1971 Technical Debrief, "I guess I thought there was not that much concentration of fragmental debris. The smaller ones appeared to me to be pretty much 100-percent covered with frags; and this, I would say, had maybe 30 percent frags."]

[Irwin, from the 1971 Technical Debrief, "Well, I thought it was 100-percent coverage."]

[Scott, from the 1971 Technical Debrief, "Did you really?"]

[Irwin, from the 1971 Technical Debrief, "It will be interesting to see what that picture (for example, AS15-82- 11085) shows."]

[Scott, from the 1971 Technical Debrief, "We may be talking about two different craters."]

[Irwin, from the 1971 Technical Debrief, "I don't think so. I remember that you went ahead because I was working on my camera, trying to get the camera to work; and you went up to the rim. You were sinking in, and I came up about 5 minutes later. I was impressed with how soft the rim was because you would sink in almost 6 inches."]

["That was a very unique crater. It was the only one of that size and that type that we saw on any of the EVAs."]

[Scott, from the 1971 Technical Debrief, "It surely was. I hope some of those clods got back intact, because they really fell apart easily. I think the photos will describe the rim better."]

[Irwin, from the 1971 Technical Debrief, "In fact, one of the photos that we saw this morning was of that crater."]

[Scott, from the 1971 Technical Debrief, "That's right; it surely was. I guess you're right. If that is the case, then that indeed was covered as much as the others (meaning the small, glass-lined craters); but it just looked different to me. It looked like more of a tan or brown or darker gray."]

[Irwin, from the 1971 Technical Debrief, "the color could have been slightly different. The fresh ones were a very light gray. The fresh ones looked like hard, angular, fragmental debris covered on the inside; and this one just didn't look quite that hard. It had a different color. It will be interesting. We sampled both types, so we could compare them."]

[Readers should note that, while Jim was usually content to defer to Dave on geology topics during the mission and the technical debrief, where there was a difference of opinion he always presented his argument firmly and clearly.]

165:11:22 Scott: Get me a...Oh, you got a bag, okay. Just a second here. (Long Pause)

[Fendell pulls back on the zoom. Every once in a while we get a glimpse of somebody's helmet over the back of Jim's seat.]

165:12:05 Irwin: Yeah.

165:12:07 Scott: Rog, Joe. (The sample in) bag number 255 is covered with dirt, but it looks just like a big piece of glass.

165:12:16 Irwin: You want me to put some fines in with this, Dave?

165:12:18 Scott: (Lost under Joe)

165:12:18 Allen: Roger. Jim, throw in a little soil there, please.

165:12:21 Scott: Here, let me have the bag. (Pause) Don't mess up where the rock was (for the "after" photo), but pick up that little glass ball next to you, too. See that little glass ball next to where you scooped up?

165:12:38 Irwin: To the west of it, you mean?

165:12:39 Scott: Yeah.

165:12:42 Irwin: This one right here?

165:12:43 Scott: Yeah. That's it. Then we're about full. Think you dropped it, Jim.

165:12:47 Irwin: Yeah. There.

165:12:53 Scott: Okay. Good. Okay. (Long Pause)

[During this pause, Dave may be taking a cross-Sun "after" from the north, AS15-82- 11109.]

165:13:21 Scott: Okay. On our way.

[Fendell starts a counter-clockwise pan.]

165:13:26 Allen: Dave and Jim, this is Houston with the news report for you.

165:13:32 Scott: Go.

165:13:34 Allen: Roger. Be advised your Command Module Pilot, Alfredo, just did a perfect plane change burn.

165:13:43 Scott: Oh, that's good news! But, we knew he would.

165:13:49 Allen: Rog. He's coming back to look for you.

165:13:54 Scott: Good for him.

[The plane of the Command Module orbit does not change relative to the stars and, as the Moon rotates on it's own axis once in 29 1/2 days, the landing site moves eastward and out from under the Command Module orbit. From the perspective of the crew on the lunar surface, the Command Module's point of closest approach moves about 30 kilometers west with each orbit. It is now about 60 hours after the landing and the closest approach of the Command Module is now about 1000 kilometers west of the landing site. About two minutes ago, at the appropriate point in his current orbit, Al Worden performed an engine burn which changed the inclination of his orbit so that it would pass east of the landing site on the next pass and, at launch time, would pass directly over the landing site.]

[Scott - "The plane change was a big deal, 'cause this was the first time anybody had to make a plane change. It's a good thing he made it."]

[Jones - "Cause you were so far north and the orbit was inclined to the lunar equator."]

[Scott - "Yes; and, also, longer on the surface, so we're moving underneath the orbit. So this is the first time that one of the guys in lunar orbit, by himself, had to make a plane change. That was good news."]

165:13:58 Irwin: Yeah?

165:14:00 Scott: I'll tell you...

165:14:01 Irwin: Your going to drive slowly. In fact, let me walk...

165:14:03 Scott: No.

165:14:04 Irwin: ...I can walk as fast as you can drive.

165:14:05 Scott: No, you can't. No way. Okay?

165:14:11 Irwin: I'll hop on, but I'll just...I don't need the belt.

165:14:18 Scott: Where's your camera?

165:14:20 Irwin: Under the...Yeah, I put it under...

165:14:25 Scott: Let me take one crack at it. Just to...Where did you put it?

165:14:27 Irwin: Oh, it's on my RCU.

[Jim probably retrieved the camera from under his seat and put it on his RCU bracket.]

165:14:35 Irwin: Okay, the master craftsman.

165:14:37 Scott: Yeah, maybe I...

165:14:38 Irwin: Yeah.

165:14:39 Scott: Take it off. I can't...

165:14:41 Irwin: I thought it would be easier to work if I (was wearing it)...(Long Pause)

[From Station 9, the bright, white crater on the east rim of St. George stands out spectacularly, even in the TV.]

[Fendell reaches the counter-clockwise pan limits. Dave and Jim are off-camera on the other side of the Rover.]

165:15:31 Irwin: Yeah, the shutter's driving, but it's not driving the film.

165:15:36 Scott: Right. Pity. (Pause) Yep; it's a problem.

165:15:46 Irwin: Right.

165:15:47 Scott: Want to carry it or chuck it in the...

165:15:49 Irwin: I think I'll just put it in the seat.

165:15:51 Scott: Yeah. (Garbled) (Long Pause)

[Fendell starts to pan clockwise, but Dave comes around the back of the Rover and the available video ends.]

165:16:48 Irwin: Yeah.

165:16:49 Scott: Ready?

165:16:50 Irwin: Ready. Okay, we're moving west. (Pause)

165:17:01 Allen: Roger.

[Dave will be driving west toward the rille and hopes that the Rover will be steady enough that the high-gain antenna will remain pointed accurately enough at Earth. After parking the Rover, Jim reported a heading of 267, just 3 degrees south of west, and Dave will try to maintain that heading to get a TV signal through to Earth. during the drive, we get occaisonal, short views of the right-front wheel with the lunar surface going past None of these views lasts more than two or three seconds. During Gene Cernan's drive to the Apollo 17 VIP site at about 169:59:42 Houston received about 15 seconds of video from the moving Rover, albeit by lucky chance.]