"It's just a word" to you, MID, but it is odd.

It is odd to use the term "damaged" to mean something else (such as "disrupted" or "altered"). Particularly when the term is used repeatedly.

Anyway, I'll ask them what they meant by the term, and let you know if I get a reply.

______________________________________________________________________________


I'd like to go back to this image, with a red arrow pointing to a region that you and Peri claim is "a brightened swath" in the lunar surface, which was caused by the LM descent engine thrust...



Now, I have huge problems with your argument, MID.

This cannot be a "brightened swath" in the lunar surface caused by the LM DPS engine plume, because it only extends out from the LM on one side, exclusively.

During the LM approach phase, the altitude decreases from 7000 to 500 feet, the range decreases from approximately 4.5 nautical miles to 2000 feet. The LM trajectory approach angle is approximately 16° relative to the surface (10.9° nominal to 13.6° maximum).

During the landing phase - from 500 feet altitude down to lunar surface - the LM maintains a trajectory of ~ 16° off the vertical.

http://history.nasa.gov/alsj/nasa58040.pdf

Therefore, the DPS engine thrust would also contact the lunar surface at ~ 16° off the vertical, throughout the LM's descent (approach and landing).

This would disrupt (or damage) the lunar surface all around the region surrounding the LM landing spot. The overall effect would be radial, or slightly elliptical, extending outward, from the LM centerpoint.

The LM would have had to approach the surface at an extreme horizontal trajectory, and have landed on its side, in order to create the one-directional "brightened swath" you say it created in the photo!

Somehow, Turb, I rather expected you would!





I shall agree that the swath extends to "one side" of the LM. In fact it extends in the direction from which the LM came, and that is generally aft of the LM, possibly a wee bit slanted to one side or another, which is in fact what you see here. Additionally, you see it extend just a little out front...a wee bit.
However, it can only be caused by the LM DPS...but let's wait on that.




I shall commend you on consulting the official documentation describing the descent trajectory phases.

However, you are mis-interpreting what you read, and drawing a rather odd conclusion regarding soil disruption.

First of all, from "High Gate" through "Low Gate" (the places you describe (i.e., ~7000FT through 500FT)) the LM guidance did maintain a 16 degree trajectory relative to the ground. During the Landing Phase, guidance maintained that plane of descent. This Landing Phase trajectory was designed and approved by flight crews because it was a satisfactory plane from which to take manual control of the spacecraft during the terminal landing phase.

You are confusing trajectory of 16 degrees with spacecraft attitude (which equates to the angle of the engine bell to the surface.)
By the time the LM was at around 200 FT, the spacecraft attitude (which was also at 16 degrees pitched up, as-it-were, at Low Gate), the attitude was being pitched flatter so as to be at about 8 degrees. At about 150 FT it was down to 6 degrees.

The computer was nulling horizontal velocity and converting the trajectory to vertical, and it could've landed the vehicle if allowed to. It never was allowed to, and all CDRs took manual control of the terminal phase. Landings all took place essentially vertically, with essentially zero attitude (engine bell flat to the surface), and perhaps a small (1-2 FPS) translational component forward or to one side.

Basically, the LM converted from 16 degrees approach path to almost none, and it's attitude from High Gate went from 16 degrees to essentially zero (meaning, essentially flat, with the crew looking straight out along the surface).


You seem to be interpreting this information as saying the the engine bell was pointing forward 16 degrees all through the landing, which would've caused exhaust to spew forward, ahead of the LM, causing a disruption ahead of the LM by some distance. This was not, and couldn't possibly have been the case. They'd have landed back legs first, and tipped forward onto the surface...not a healthy way to land a LM, and the thrust vector would've been working to push them slightly backwards at that point, which would've made for a really wierd landing...and maybe a catastrophic one...
However, they certainly could've landed with a 16 degree approach path. That's no problem at all in level flight at low velocity. 1 FPS vertical velocity would have a forward translation of 3 FPS at touchdown, for instance, no big deal.


However, it really doesn't matter...because engine exhaust disruption only is caused where the engine exhaust impacts the surface. If you're moving from point A to point B, and the engine exhaust touches the surface along that line, you're going to get disruption along that line, but when the LM stops at point B, that's where the disruption essentially stops, thus, the disruption pattern would logically appear to be off in essentially one direction from the LM, the direction from which it came, primarily, and that is what you see in this photo. There is no physical reason for any uniform disruption out in front of the LM.

It's always nice to find a point we can agree on, despite our opposing views!



That makes sense to me, as well.



I agree.



You're saying "point A to point B" is a [i]lateral[/b] movement by the LM, as it hovers above the surface?



And you're saying "point B" is where the LM stops moving laterally, still hovering above the surface?

And from that point, the LM begins its vertical descent, until it lands on the surface?


This makes no sense to me, MID.

What is the LM's altitude while "moving from point A to point B"? What evidence supports this claim - photos, videos, etc.?

Why would the final vertical descent to landing (after "point B") not disturb the entire area surrounding the LM?

I'll await your reply, before I continue...

Turb...

Imagine a Harrier jet coming in for a vertical landing on an aircraft carrier. As it approaches the carrier, it gradually slows its descent and forward speed until it is hovering next to the carrier, then it maneuvers laterally until it is right over the landing deck, then reduces thrust and drops to the deck.

The LM landed in a similar manner. As it neared its landing spot, it gradually reduced its horizontal and vertical speed, using a combination of the RCS thrusters and the DPS throttle, until it was essentially hovering over that spot. At that point, the DPS was operating at only approximately 10% - 15% of its maximum rated thrust. As fuel was constantly being consumed, the overall weight of the LM was constantly reducing, requiring the thrust to constantly be reduced to keep it in a hover. The thrust was then reduced further to allow the LM to slowly drop down to the surface until approximately 6 feet above the surface when the Lunar Surface Probes on 3 of the landing gear legs touched the surface which lit the "Contact" light. The DPS was then shut off and the LM dropped the final few feet, unpowered, the the Lunar surface.

All this took place in the final few seconds before landing. I believe Apollo 14 was the only landing where the DPS was still running when the LM actually touched down.



Cz

Another observation is that, according to the astronaut debrief comments, in the final descent to landing, they did all they could to be either stationary or moving slightly forward at touchdown. They could not see behind them, and didn't want to land on/in something back there. It's a common theme in the landings.

I appreciate your comments, Czero, but the problem is that it doesn't get to the crux of the issue.

MID - from my take - seems to be claiming that just prior to its final vertical descent, the Apollo 15 LM moved laterally from "point A to point B", while hovering above the lunar surface, and that this explains the one-directional "brightened swath".

That's why I've asked him to provide evidence to support that claim, and to specify what the LM's altitude was during this lateral maneuver. He hasn't yet replied, but I've found some relevant info, from the ALSJ...

104:39:32 Irwin: 7000 feet. P64!

104:39:36 Scott: Okay.

104:39:37 Irwin: We have LPD.

104:39:40 Scott: LPD. (Pause) Coming right.

[O'Brien - "Now that the landing area is in sight, Dave is making the first of 18 redesignations of the landing site, correcting the approach path to the right moved the targeted landing site to the north."]

104:39:45 Irwin: Four-zero (LPD angle)

104:39:47 Irwin: 5000 feet. (LPD angles) 39. 39. 38. 39.

104:39:56 Irwin: 4000 feet. 40. 41. 45. 47. 52.

104:40:06 Irwin: 3000 feet. 52. 52. 51. 50. 47. 47.

104:40:21 Irwin: 2000 feet. 42.

104:40:26 Scott: Okay. I got a good spot.

104:40:28 Irwin: Good. 42. 43.

104:40:31 Irwin: 1800 feet.

104:40:32 Mitchell: Falcon, Houston. You're Go for landing.

104:40:33 Irwin: 44. 45.

104:40:36 Scott: Rog. Go for landing.

104:40:39 Irwin: 44. 45.

104:40:43 Irwin: 1000 feet. 45.

104:40:47 Irwin: 900. 45.

104:40:49 Irwin: 800. 45.

104:40:53 Irwin: 700. 46.

104:40:58 Irwin: 600. 48.

104:41:02 Irwin: 500. 49. Minus 17 (feet per second descent rate). Minus 15.

104:41:08 Irwin: 400 at minus 14. You've got P66.

104:41:13 Scott: Okay.

"Because Dave disengaged the Landing Point Designator function when he assumed manual control, he no longer wants angles but, rather, his rate of descent. Below an altitude of 500 feet, they are flying in what Dave described in a 1995 letter as the 'zone of unforgiveness'."

[Scott, from the 1971 Technical Debrief - "We got down to 400 feet, and we had planned to switch to P66. I gave one ROD click at that time. Jim called me on the P66, which verified the ROD was working, and I went down to 200 feet and started rounding out (that is, slowing the descent), at 150 feet."]

104:41:15 Irwin: 300 feet. Minus 11. (Pause) Minus 11.

104:41:22 Irwin: 250. Minus 11; 9 percent fuel (remaining).

104:41:28 Irwin: You're 200. Minus 11.

104:41:31 Irwin: 150. Minus 7. Minus 6.

104:41:36 Irwin: 120 feet. Minus 6.

104:41:39 Scott: Okay. I've got some dust.

[Scott, from the 1971 Technical Debrief - "I could see dust - just a slight bit of dust. At about 50 to 60 feet, the total view outside was obscured by dust. It was completely IFR (Instrument Flight Rules). I came into the cockpit (that is, switched his attention from the view out the window to the instrument readings that Jim was giving him) and flew with the instruments from there on down."]

104:41:40 Irwin: Minus 5; 100 feet at 5; nine percent fuel; minus 5.

104:41:46 Irwin: 80 at 5. Minus 3.

104:41:51 Irwin: 60 at 3.

104:41:54 Irwin: 50 at 3. Cross-pointers look good.

104:41:58 Irwin: 40 at 3.

104:42:02 Irwin: 30; 3.

104:42:05 Irwin: 25; 2; seven percent fuel.

104:42:12 Irwin: 20 at 1.

104:42:14 Irwin: 15 at 1. Minus 1, minus 1; six percent fuel.

104:42:22 Irwin: 10 feet. Minus 1.

104:42:27 Irwin: 8 feet. Minus 1.

104:42:29 Irwin: Contact. (Pause) Bam!

http://www.hq.nasa.gov/alsj/a15/a15.landing.html#1043932

I've bolded "1800 feet", because this is when the LM begins its vertical descent to landing on the surface. Also, note that no dust is observed until the LM descends to 120 feet altitude, and by 56-60 feet altitude, it totally obscures their view out of the LM windows.

This confirms that the LM could not have created the "brightened swath", as claimed by MID and peri. The final vertical descent to landing began from an altitude of 1800 feet, so any prior lateral movement would have been above 1800 feet. Therefore, any such maneuver would have had no effect on the lunar surface.

The footage of the LM descent and landing provides further confirmation.

Yes we did land on the Moon . Isnt there anything else you can think of that just might be more important rather then believe what the skeptics are telling you.

Turb,

Watch the landing movie by Kipp Teague on the Apollo Lunar Surface Journal Apollo 15 video page. It clearly shows that the LM was still translating horizontally at a pretty high rate at 1800 feet altitude. The near-vertical final descent to touchdown did not begin until about 120 feet altitude. The ALSJ landing transcript you quoted includes a comment from Dave Scott that he "started rounding out at 150 feet." This pitch down to final landing attitude is pretty obvious in the video.

Here's a portion of the ALSJ's annotated detail of panoramic camera frame A15-P-9809. I've added to the image the approximate ground track of the LM as seen in the video clip. The craters seen in the video clip perfectly match those along the track I've drawn. I've marked out a few rough points to tie in with the crew's altitude callouts.



Using the landing movie as evidence, I estimate that the LM was at or below 300 feet altitude and still translating horizontally when it passed over the area of this image which shows noticeable brightening.

Turbs

It sounds as if you're saying the LM descended vertically from 1800 feet, with little or not horizontal component velocity: is that right?

How do you come to this assumption? Despite you saying the footage of the LM descent confirms this, it actually contradicts what you're saying.

http://history.nasa.gov/alsj/a15/ap15_descent.mpg

Check out the above link, it shows the landing (with audio) from 3000 feet. There is quite clearly a substantial lateral component to velocity up until around 100-120 feet above the surface. Look at the still below (from the start of the descent film), I've highlighted the Apollo 15 landing site in red.



And here's a still from the 26 second mark, at 1800 feet. Clearly the LM isn't above the landing site.

Turb:
I think you're mis-interpreting what you see again.
In the AS-15 Technical Debrief, as well as in the links provided at ALSJ, it is clearly stated that Falcon landed with ~1 FPS forward velocity.
Beginning their "vertical descent" means that they started coming down at a greater rate, but no one dropped from 1800 feet straight down. They were moving horizontally the whole time, bleeding off horizontal velocity gradually as they descended.

The computer controlled the descent, which includes both verticle and horizontal components of the trajectory, and at 1800 feet, the crew had not yet selected P66. P66 allows for manual attitude control and incremental rate of descent inputs. They didn't engage P66 until 400 feet, so they couldn't have commanded the vehicle to go straight down at 1800 feet, and no one would...as you were being targeted to a landing point by the computer still off in the distance. Further, you wanted to be closer to the surface before manually taking her straight down, and Dave Scott did that, and as indicated, landed with about 1 FPS forward velocity.

They were moving horizontally at ~130 feet, when they started seeing dust flow. Thus, it is entirely possible, and in fact a definite, that the swatch you see was in fact probable, and in fact absolutely there.


Otherwise, the responses that have been posted have been very clear and precise, and I can't add anything to them!


p.s.: if you watch that descent video, you will clearly see the horizontal component in the descent well below 1800 feet...

No, they were moving vertically when they started seeing dust flow, not horizontally. That is confirmed by the ALSJ and the video.

104:41:15 Irwin: 300 feet. Minus 11. (Pause) Minus 11.

104:41:22 Irwin: 250. Minus 11; 9 percent fuel (remaining).

104:41:28 Irwin: You're 200. Minus 11.

104:41:31 Irwin: 150. Minus 7. Minus 6.

104:41:36 Irwin: 120 feet. Minus 6.

104:41:39 Scott: Okay. I've got some dust.

And, as shown above, they first mention seeing the dust 3 seconds after descending to ~120 ft. altitude, not ~130 ft. So, they were actually a little bit lower than 120 ft. when they first saw any dust.There is no dust seen in the video during the LM's horizontal movement. At ~ 1:29 mark of the clip, the only movement of the LM is vertical, and the dust appears in the clip at ~ 1:46 mark.

Another important point here is that the dust only starts to be seen when the LM has descended to <120 ft. altitude.

But.. "At about 50 to 60 feet, the total view outside was obscured by dust."

That obviously means the LM is blasting up much more dust when it is 50-60 ft. above the surface than at ~120 ft. altitude.

But the photos don't show the slightest evidence that a 50-60 ft.-high dust cloud had been stirred up by the LM landing, which had totally obscured their view!! The entire area looks virtually undisturbed.

The photos totally contradict what the ALSJ describes, and what the video clip shows.

Where do you see the effects of a ~60 foot-high dust cloud enveloping the LM?

Why does the dust cloud have to be 60 ft high? A layer just above the surface can still conceal the surface.

Turbo, the numbers being read off are altitude and rate of descent (in ft/sec). Where do you determine there was no forward movement? Again, forward, and somewhat to the side, is where the crew could see. They did not want to move backwards. And the crews specifically said they wanted to be slightly moving forward, if at all, during the final landing maneuver. They were all but hovering in the last 50-100 feet, moving forward slightly. The debriefs say as much.

Turb, Jim was not calling out any horizontal movement numbers to Dave, only vertical. The video clearly shows horizontal movement. It then shows the vehicle pitching level and coming down virtually straight during the final phase. What it also shows is very clearly, that at about 10 feet, Dave was in fact translating forward, as is indicated in his Pilot's Report, and in the Mission Report, and in the Technical Debriefing.

You're not actually going to nit-pick about 10 feet are you?
The Mission Report states ~130 feet. Dave and Jim said around 120 feet when they started picking up some dust. What's the difference? Obviously they saw dust being kicked at that point, some distance horizontally from the landing site. Just because you don't see dust on a 16mm film shot from a LM window doesn't mean that the crew, with eyeballs looking with ever so slightly higher acuity, did not. They did.




...

Turb, we've been through this before, in depth.
What gives you the impression there was a dust cloud, let alone a dust cloud 60 feet high enveloping the LM?

To somewhat expand on Swanny's comment...

There were no dust clouds on the Moon. It was a sheet of dust, radiating out on a ballistic arc. No cloud enveloped the LM, and none of this dust ever touched the LM.

Their view was obscured because the thickness of this sheet of flying dust was denser when they got down closer to it. This is merely logical. There is absolutely nothing to tell you they were "inside" this dust sheet. In fact, they weren't, they couldn't have been. The dust was below them, an indeterminate distance, and moving away from them.

You're right that they were kicking up more dust as they got down closer, but the idea that they were enveloped in a cloud of dust is erroneous.

The fact is, the LM moved horizontally across the ground, and it disturbed dust as it did so from about 120-130 feet until engine cutoff. The swath of dust disturbed by the DPS had to be somewhat eliptical, and would naturally extend out behind the LM, not out in front of it. There were certainly moments of vertical only descent, especially as they got close, but it definitely had a forward component to it at touchdown.

...this was what all pilots did. You wanted to be able to see ahead where you were landing. You didn't want to be backing up and touching someplace you couldn't see.

Further, one would expect that this type of descent would produce a brightened swath that would be a bit brighter around the area when the LM approached closer to the surface. That's exactly what is seen.

Incidentally, Turb,

You might be interested to know that your post of today was the 4,061st post of this thread, which broke the record length of the old Moon Hoax thread.

You have made this thread the new Grandaddy of Moon Hoax threads...

Somehow, it seems rather approriate that our most esteemed HB should be the one to have broken the record!

Further, I must say that this thread (which is now a full fledged rope!) has been a heck of a lot more civil than the last. Certainly, we've had one or two folks lose their on-line lives here in this thread, but still, that's nothing compared to the last one, which at the end, resembled a war zone.

I'm glad we're not seeing that here on this one.

Incidentally - the dust kicked up could travel a fair ways away from the site. One of the Apollo landings happened 200 meters away from an old unmanned probe that had landed on the moon some years earlier - they went there so they could take some pieces back and see the effect of the lunar/space environment on the materials. When they walked up to it, the surfaces facing away from the lunar lander were pristine but those facing the lander were covered by a *very* thin sheen of dust. We're not talking the surface obscured, just enough dust particles stuck to the surface to make it visibly a slightly different color.

OFCOURSE WE WENT TO THE MOON!!! IT WAS ON TV HELLO!

Sure...that was Apollo 12.
There's no doubt, the dust, travelling outward propelled by a rather high velocity gas stream, in vacuum, would travel quite a way in 1/6 g conditions.

Most observations of this dust sheet by LM crewmen indicated that the dust disappeared out toward the horizon. I'd say hundreds of meters is certainly possible.

Shhhh...


Shouting is so impolite, Zaus.

You know, there is a school of thought out there which might say, "Just because it was on TV doesn't mean it was real."
And in considering the quality of modern popular product on TV today, that argument holds alot of weight.
...I know, I sound like an HB...bear with me.

The point is, the fact that Apollo was broadcast live on TV doesn't seem to satisfy a certain segment of the populus as to Apollo's reality, as amazing as that may seem. Perhaps the modern technology that makes the most implausible and often ridiculous things seem real today effects their perceptions of what was actually real many years past.

Thus, we're here to show folks the rest of the story (which all HBs are lacking in knowledge of...without exception). Teaching the facts, and the undeniable reality of this magnificent effort is the purpose of this thread.

This thread is over 4000 posts long now. I think if you took a little time to go through some of it you'd see that such statements as the one you yelled out in CAPS is hardly sufficient to convince any non-believer.

The fact that it was picked up as a TV signal with directional antennae pointed at the moon is a better argument. This isn't just NASA saying so, either. There are first-hand Russian and Australian accounts available:
http://www.novosti-kosmonavtiki.ru/content...rs/271/03.shtml
http://www.parkes.atnf.csiro.au/news_events/apollo11/
http://www.honeysucklecreek.net/Apollo_11/index.html

As usual, Swanny makes an exceptionally pertinent and astute point!

During landing, the impact of rocket exhaust with the surface produced dust clouds. On some missions, dust became visible 30 to 50 meters above the surface, and during the final 10 to 20 meters of descent, the surface was largely obscured by the dust cloud.

http://www.lpi.usra.edu/lunar/missions/apo...xperiments/smi/

And, as noted earlier, from the ALSJ....

"At about 50 to 60 feet, the total view outside was obscured by dust."



As noted above, there was a cloud of dust, which had totally obscured their view when the LM descended to an altitude of 50-60 feet.

The two triangular windows of the LM are indicated by the green arrows I've added....



"At about 50 to 60 feet", their "total view outside was obscured by dust".

"..dust became visible 30 to 50 meters above the surface"

The LM was enveloped in a dust cloud. But the photos contradict that, which is a real pickle for Apollo supporters.



No. Again, the video shows dust only during the final vertical descent, and dust first appears (and is first reported by the LM crew) when the LM is ~ 120 feet altitude.

There is virtually no detectable horizontal (or lateral) movement from 120/130 ft. altitude.



MID, this comment refers to the LM's lack of any 'rear-view' windows! The LM windows only gave them a "forward" view of the external environment, so they had no choice but to 'inch' the LM in a forward direction to have any hope of seeing where they were going.

That became very difficult - even impossible at times - once the LM began its final vertical descent to the surface. As indicated by both the video and the ALSJ, the dust first appeared upon descending to ~120 ft., and had totally obscured their view at 50-60 ft. altitude.



No. One would - and should - expect this type of descent to produce a very noticeable disturbance of the lunar surface region all around the LM - as shown from the activity in the video, and further confirmed by comments from the ALSJ Mission Report.


The only thing I've seen held up for your counter-argument is a photo (or two), alone among the many hundreds of other photos. Yet even this single photo you've offered as evidence of "a brightened swath created by the LM", shows several other regions which appear to be "brightened swaths".

A much improved and healthier thread, I do agree!

Turbo, if I read your post correctly, you're saying that the dust created a "cloud" that not only spread laterally across the surface, but that it rose from the surface several meters...like in billowing?
The missions had varying amounts of dust on landing, some almost completely obscured the surface, while others had no trouble picking out surface features (rocks, craterlets, etc) to help judge horizontal movement on final descent. The problem wasn't billowing (it didn't), but a fast moving spray of dust moving out from under the engine. The dust was being propelled laterally across the surface. This obstructed their view of surface details to varying degrees, making it difficult to visually judge lateral movement. The astronauts indicated the dust was being propelled towards the horizon, rapidly.
The LM was not enveloped in a cloud of dust near the surface. And just because there was no discernable dust being kicked up on approach doesn't mean the LM exhaust wasn't altering things around down there on a small scale. Frankly, it would be nice to be able to see better pictures of the landing sites, but for the moment they aren't available. I'm sure there will be some one day. Just costs a lot of money to send things up there.

It's not a "pickle", Turb. It's a matter of semantics.
You're clinging, once again, to a use of phraseology that is typical, but of course inappropriate technically.

The term "dust sheet", or perhaps "dust cone" which is actually what did and what must happen, isn't exactly conducive to understanding, despite the fact that "dust cloud" invokes something that cannot happen in vacuum.

You interpret the usage of this recognizable term to envision the LM enveloped in a "cloud" of swirling sust, which should've, in theory, provided some existence of itself by perhaps some dust film all over the LM.

No such thing was possible, or even plausible in vacuum, since all the dust was propelled away from the LM by DPS exhaust gasses, and since none was interacting with molecules of atmosphere, which produces clouds on Earth. The fact that one could see the dust is no indication that it was a cloud. It merely says it was dust being blown.

Obscuration of the surface was a function of how much dust was being thrown. It varied depending on where one landed. You couldn't see the surface because the dust blocked it, not because the LM was "enveloped" in an impossible cloud of swirling dust.







Of course. That's what I said.



No, it wasn't impossible. They flew by their instruments. They had complete output available as to horizontal and verticlal velocity..just like a pilot of an airplane has on Earth when landing on instruments in low weather.





Do you know what causes brightened swaths on the lunar surface, other than LM DPS exhaust?

Virtually all craters show these lightened areas around their perimeters...ejected dust, etc....

I'm no scientist but I've got a question that's probably got a simple answer. In all the pictures taken on the moon the shadows were at least the size of the object making the shadows. That means that on earth when the shadows are the approximate same size, it's still daylight. Why on the moon is the sky dark but there's still light on the ground? I've never seen that happen here. If there are still shadows here the sky is still light. That's all I am curious about. Thanx

The "sky" is dark on the Moon during the Lunar Day because there is no atmosphere to diffract sunlight as it passes through it.


Cz

Actually, I was presenting some material from NASA sources - such as the video clip, and the comments below - which effectively are "saying" that....

"During landing, the impact of rocket exhaust with the surface produced dust clouds."

"...dust became visible 30 to 50 meters above the surface.."

"At about 50 to 60 feet, the total view outside was obscured by dust."



Is your comment that "The problem wasn't billowing (it didn't)" only your personal view/opinion on the matter? I'll assume it is, since you've not held up any evidence to support it as a valid claim.

Another point ~ 50-60 ft. above the surface, "the total view outside was obscured by dust."

That means nothing could be seen outside the LM - not just the surface. If there had only been a "sheet" of dust, well below the LM, after it had descended to ~50-60 ft. altitude, they would still have had a view of the outside. The view outside the two LM windows could not have been totally blocked by the dust, if it had only "propelled laterally across the surface", in some sort of expanding "sheet", just a few feet high, some 40 or 50 feet below the LM!!

If so, then at ~50-60 ft., they would have said something to that effect - ie" "When the LM had descended to 50-60 ft., we took a look outside the window(s). Some 40-50 feet below us, the dust was rapidly expanding outward like a vast 'sheet', just a few feet above the surface."

That argument is nonsense.

As I've noted, the ALSJ account (the 50-60 ft. comment) effectively kills the argument that only the lunar surface couldn't be seen outside the LM due to dust.

Regarding the technically correct term(s)?

I've already cited from this source....

During landing, the impact of rocket exhaust with the surface produced dust clouds. On some missions, dust became visible 30 to 50 meters above the surface, and during the final 10 to 20 meters of descent, the surface was largely obscured by the dust cloud. On other missions, the dust cloud was not as dense and the surface remained clearly visible throughout the landing.

http://www.lpi.usra.edu/lunar/missions/apo...xperiments/smi/

This is from a Oct. 2007 paper, and it gets even better (or worse, depending on how you see it)....

The President's Vision for Space Exploration calls for the return of human exploration of the Moon. The plans are ambitious and call for the creation of a lunar outpost. Lunar Landers will therefore be required to land near predeployed hardware, and the dust storm created by the Lunar Lander's plume impingement to the lunar surface presents a hazard. Knowledge of the number density, size distribution, and velocity of the grains in the dust cloud entrained into the flow is needing to develop mitigation strategies.

http://ntrs.nasa.gov/search.jsp?R=701132&a...rvestDate%257c1

You surely see now, MID, that your very own sources - direct and/or linked NASA sources repeatedly call it a "dust cloud", and even call it a "dust storm" once (or maybe more!?)

But so far, I haven't seen them call it a "dust sheet", or a "dust cone", in either these specific documents, or in any of the others I've been able to find.

Now, this doesn't mean we can conclude, beyond any doubt, that neither of these 2 terms are used anywhere, in any NASA - approved paper. It's quite possible that somewhere, it's described as a "dust sheet" or a "dust cone" in a document(s) I've not come across to date.

But we can conclude, beyond any doubt, that NASA itself calls it a "dust cloud".

Turbo, while at ALSJ, have a look at the tech debriefs for the missions. This was a step by step detailed debrief of each mission and goes into great detail. You are quoting remarks made in a paper by the Lunar and Planetary Institute, and this is not "NASA". Their use of the term "cloud" has you thinking of Earth type clouds.
From the Apollo 17 tech debrief...Cernan..."The dust layer was so very thin that I could definitely see through it all the way down. It didn't hamper our operations at all...visibility through the final phase was excellent".
Apollo 16 (Young)..."Yes, 80 feet. Certainly it started there, and it got a lot worse, but you could still see the rocks all the way to the ground".
Apollo 12 ran into a lot more dust, reportedly starting around 300 feet, and Conrad was basically on the 8-ball for the final descent as he had difficulty determining his attitude by "looking at the horizon" (not looking "for" the horizon). He never mentioned being enveloped in a billowing cloud of dust. Were there such clouds, one would expect to see the LM covered in dust after landing. (this explains the lack of dust on the footpads...no atmosphere, no turbulence/billowing).

Where in the ALSJ did it say the outside view was totally obscured? Conrad reported difficulty seeing through the dust layer ""I had no problem with the dust, determining horizontal or lateral velocities, but I couldn't tell what was underneath me". "All I knew was that there was there was ground underneath that dust". The dust was below them, in a thin layer near the surface. This layer varied in opacity with the landing site.

Edit: Found it, Apollo 15, David Scott: "At about 50-60 feet the total view outside was obscured by dust. It was completely IFR. I came into the cockpit and flew with the instruments from there on down." Later in the debrief he mentions "I think the dust is going to be variable with the landing sites." What he meant by "completely IFR" and "obscured by dust" is interesting, but I really don't think the LM was enveloped in a dust cloud.

What Cz said...

To elaborate a wee bit, whenever you look at any picture shot in space in sunlight, whether on the Moon, or on orbit, you'll note shadows being cast by sunlight and always a completely black "sky" in all of them.

No atmosphere = black "sky".

I believe I addressed the semantics involved in that usage.
You're clinging to a term used for clarity, and understanding. Much as you seemed to cling to the use of the term "damaged" in another source you cited, as if that meant something significant. It did not.
We know how dust behaves in vacuum. Clouds, as we see in an atmosphere, are not possible. I can see that NASA refers to dust clouds. That's not an issue, and its well understood why they would.

As I've indicated, this is not an opinion. Billowing can only occur when fine particles interact with an atmosphere. This is well known and completely rational, and was demonstrated on every Apollo landing, as well as by the men on the surface when they disturbed the surface dust. The evidence of this completely natural occurrance is abundant.



Turb, we're talking about a pilot report given by a man who was landing a LM on the lunar surface.
His view was spring loaded to one direction: down. If he was looking out at the horizon, or up, or anywhere else during the terminal phase, he needed to be slapped...which he didn't, because he wasn't looking anywhere but down. That view was totally obscured by the flying dust below him...just like the surface of the ground on Earth can be completely obscured by a layer of ground fog below an aircraft.

All he saw was the dust below him, obscuring the surface. He had no time or inclination to look out toward the horizon, or any interest in estimating how high the dust went as it travelled outward. It might have been a hundred feet high out in front, but we'll never know, because any pilot landing a LM is looking down, and no where else.

What he said about the dust was all that was necessary to explain the circumstances. The dust obscured the view of the ground at the landing area. What is nonsense is thinking that anything else should've been said, or that the LM crew might have been looking anywhere else but down. The CDR was looking down, and the LMP was staring at the displays the whole time, feeding the CDR information. No one on board that craft was looking around anywhere else, and certainly didn't notice anything save the obscuration down, which was all that mattered.

From the Johnson Space Center Oral History Project - Neil Armstrong Interview, Sept. 19, 2001:

Regarding dust:



Cz

I'm certain that if a trained astronaut/test pilot is dumbfounded by peculiar phenomenon in the lunar vaccuum, others of us would be tempted to call it impossible. It's completely understandable, the Moon is by every definition an alien environment. Strange stuff happens there, compared to out terrestrial paradigm. With a little study and thought, it all makes sense, strange as it is.

I think you have a point, Mr. B.

• Thanks to Cz for posting (again...it's buried in here someplace else, I sure) reference to Neil's comments regarding the dust.

But this aspect of dust behavior has been explained ad-nauseam, and yet we see complete disregard for that well established and quite natural behavior because of the use of the term "dust clouds" in NASA publications. In communicating with the public, it's rather ungainly to think of a more appropriate term for dust flow in vacuum...people wouldn't understand it.

Neil, of course, was a trained man, an engineer of high ability, and a research pilot. He fully understood that this behavior was natural, but, seeing the phenomenon happen for the first time in human history still makes it rather dumbfounding, especially since the circumstances of the moment lent themselves to absolutely not thinking about that one bit.

About two or three seconds prior to that astounding observation, he had just landed a spacecraft on the surface of the Moon...the ancient dream of humanity; that which the past 7 years of his life had been devoted to...along with several hundred thousand other folks...
His heart was still betaing 150 times a minute, and the exhilaration of having succeeded was just flooding his being.

I think under those circumstances, the sight of the dust scooting away and disappearing out toward the horizon, an absolutely understandable, yet certainly other-wordly sight never before seen by human eyes, might be dumbfounding indeed.


...at any rate, it did just that, it was perfectly natural, and there were no dust clouds on the Moon, because there can't be.

I still don't understand fully about the black sky, but there's no need for me to understand it fully. I was just curious about that. Thanx Cz and MID.

just google "why is the sky blue"...look at photos of the shuttle and ISS in space...the environment in earth orbit is basically no different that that of the lunar surface. No atmosphere with the sun in the sky=black sky.

Odie

Many Apollo photos taken on the lunar surface actually show the sun in the frame, take this one for example (please note the actual size of the sun is much smaller than it looks here: this is a photographic effect called glare caused by bright sunlight striking the surface of the lens).



Lack of atmosphere on the moon means no amount of sunlight will make the sky look blue. Here on good old Earth, sunlight is affected by the atmosphere.

"The blue color of the sky is due to Rayleigh scattering. As light moves through the atmosphere, most of the longer wavelengths pass straight through. Little of the red, orange and yellow light is affected by the air."
Source

From Wikipedia - Diffuse Sky Radiation


On the Moon there is no atmosphere to scatter the light, therefore, all you will see is the blackness of space when you look up.


Cz

OK, now i get it. I think everyone's input answered all my questions. My thanks goes out to all who straightened me out on this subject.

Thanx everyone odie

I know the LPI is not "NASA". I said it's linked to NASA, which it is. And as I noted, NASA itself does describe it as a "dust cloud", and even a "dust storm". I'm not really sure what you mean by "Earth type clouds".



Yes, one would expect to see the LM covered in dust after landing, if the dust had enveloped the LM. Which it certainly appears to have done, in the video clip, and from the ALSJ account. This is one of the big problems with the Apollo photos - they don't show a speck of dust anywhere on the LM. Nor do they show any evidence of so much dust being displaced from the landing. These are significant issues which cannot be explained away by Apollo supporters.



An opinion to which you're entitled. However, that does not explain away all the dust seen in the video and mentioned in the ALSJ.

Turbs, half your problem is that you make it way too difficult for even yourself to understand.

"Dust cloud" is just a way of saying what was experienced that is easier for lay people to understand, rather then saying a "sheet of dust". Most people would have no idea what a "sheet of dust" is and to explain it would require the use of a lot of technical and scientific terms that the average person - the ones who most of the articles and PAO publications were aimed at - would have a hard time understanding. So while it is not technically correct, it gives the person reading the article an idea they can relate to of what happened and what was observed.

And "Earth type clouds" means clouds that you'd find on Earth, or any other planetary body with sufficient atmosphere to support the formations of clouds. That's not really that hard to understand is it?


No, one would not expect the LM to be covered in dust, and the "significant issues" are only significant to you and have been explained to you several times here and I'm sure elsewhere. The evidence of displaced dust under the LM is there. The fact that you can't or refuse to recognize it is not proof of anything other than your refusal or inability to understand what is being show and explained to you.


The video record of the landing shows exactly what was predicted (and then confirmed) to happen to the dust on the 1/6th gravity, vacuum surface of the Moon. Again, just because you can't or won't understand it is NOT EVIDENCE of a conspiracy or a cover up, but is definite proof of your lack of knowledge, understanding and willingness to learn.

Bottom line here, Turbs is that you still have no proof or evidence of what you allege to have taken place. Your opinions are NOT proof. Your misunderstandings and willful ignorance is NOT proof. The answers and proof have been given to you time and time again Turbs. The fact that you keep returning to these items and decrying them as proof of a hoax just shows that you have no intention of ever truly learning about the subjects at hand and are happy to remain stuck in your world of conspiracies and ignorance.


Cz

!?! I'm "clinging" to a term?!? Come on, MID, you can obviously see that I'm only using the very same terms the actual sources use. Such as NASA, and the scientist(s) heading the project re:Clementine images.

Apparently, I have to remind you that this is also the proper way to reference the sources cited in one's posts.

Why? Well, because if you don't "cling" to the same terms used by your sources, then it becomes your personal interpretation of the material. A person often does this in order to 'make it fit' with his argument or viewpoint. And that's what you've done here, MID.

The source said "dust cloud", a term which does not fit in with your argument, but fits with mine. I asked you if any sources called it a "dust sheet", because I haven't seen it described that way. It seems you came up with it on your own, to 'make it fit' your argument by claiming that they really meant something else, like "dust sheet".

And to..er...'accuse'...me of "clinging" to the same terms used by the sources, as if the terms "meant something significant"?!!

That's beyond absurd.

Again - if they really meant "dust sheet" instead of "dust cloud", then they would have said "dust sheet".

Changing the source's own term (dust cloud) to a term with an entirely different meaning (dust sheet) is pure speculation on your part. And irresponsible.

Where do you get the nads to come up with all this claptrap, and present it as if it's a well established statement of fact?

I can just picture it -

NASA: "Yes, the reason we called it a 'dust cloud' is so that Joe Public would understand what we mean. It's actually a 'dust sheet', but Joe Public wouldn't know what that meant. And we couldn't explain it to them anyway, without using lots of technical gibberish far beyond their limited knowledge and intelligence."





"Earth type clouds" could have also meant "Earth type dust clouds", especially since we've been talking about dust clouds.

But we haven't been discussing clouds in Earth's atmosphere, so yes, it is hard to understand why you're bringing them up!



What a surprise, ending a post with typical rhetoric about how we conspiracists are incapable of grasping the teachings of supreme authorities in the pro-Apollo camp. Oh well, it's always good for a laugh.

Perhaps you can enlighten me as to why the dust totally obscured their view outside the LM at ~50-60 ft. altitude, if there was only a 10 ft. high (at most) "dust sheet" below them?

What is beyond absurd is clinging to a belief system with zero evidence to support it vast amounts of evidence to show it is wrong and then constantly arguing petty semantics and pretending it's real evidence. What is beyond absurd is to ignore all the worlds leading experts on a subject an believe that one's own intrpretation of two words proves them all wrong.

I'm not the one who changed a "dust cloud" into a "dust sheet" based on nothing but one's own personal feeling. That's interpretation.

We've reached a new low when people admonish you for using the same terms as the source uses, but approve of those who make up entirely different terms.

What if I had been the one making up a new term, and the pro-Apollo people were "clinging" to the same term as the source used?

We know the answer to that, don't we?

It's not interpretation when you can look at all the landing videos and see for yourself what the dust is doing. The way it just vanishes when the engine stops is unlike any dust cloud seen in an atmosphere.

I came across this recently:
http://www.abc.net.au/science/news/stories/2005/1531577.htm
It describes how a new radioactive dating technique (hafnium/tungsten) has been applied to the Apollo samples to get a date for the formation of the moon.
My admiration for those clever NASA hoaxers grows every time their fake samples pass a new test that wasn't thought of in the sixties.

http://hashemsfilms.com/component/option,c...emid,40/id,517/

We are in contact with aliens, like in MiB, they dont want to tell the masses because they think peopl would freak out.

And apollo was faked