Where's the dust?

[PhantomWolf]

[Armstrong, from the 1969 Technical Debrief - "I first noticed that we were, in fact, disturbing the dust on the surface when we were something less than 100 feet; we were beginning to get a transparent sheet of moving dust that obscured visibility a little bit. As we got lower, the visibility continued to decrease. I don't think that the (visual) altitude determination was severely hurt by this blowing dust; but the thing that was confusing to me was that it was hard to pick out what your lateral and downrange velocities were, because you were seeing a lot of moving dust that you had to look through to pick up the stationary rocks and base your translational velocity decisions on that. I found that to be quite difficult. I spent more time trying to arrest translational velocity than I thought would be necessary."]

[Brinkley: "Was there anything about your Moon walk and collecting of rocks and the like that surprised you at that time when you were on the Moon, like, 'I did not expect to encounter this,' or, 'I did not expect it to look like this'? Or included in that, the view of the rest of space from the Moon must have been quite an awesome thing to experience."]

[Armstrong: "I was surprised by a number of things, and I'm not sure (I can) recall them all now. I was surprised by the apparent closeness of the horizon. I was surprised by the trajectory of dust that you kicked up with your boot, and I was surprised that even though logic would have told me that there shouldn't be any, there was no dust when you kicked. You never had a cloud of dust there. That's a product of having an atmosphere, and when you don't have an atmosphere, you don't have any clouds of dust."]

["I was absolutely dumbfounded when I shut the rocket engine off and the particles that were going out radially from the bottom of the engine fell all the way out over the horizon, and when I shut the engine off, they just raced out over the horizon and instantaneously disappeared, you know, just like it had been shut off for a week. That was remarkable. I'd never seen that. I'd never seen anything like that. And logic says, yes, that's the way it ought to be there, but I hadn't thought about it and I was surprised."]

[PhantomWolf]

jayutah said:

[Second, the lunar module's landing feet are well above the surface and the dust sheet when the engine is cut off and the dust sheet goes away. The engine is typically stopped at an altitude of 1.5 meters. How long it takes the LM to fall that 1.5 meters in lunar gravity is left as an exercise to the reader.

Going for my "I corrected JayUtah" T-Shirt here.

With Apollo 11, this isn't quite accurate. In fact Neil did intend to shut off the engine when the contact light come on (1.73m above the ground) but he didn't, because he missed the call from Buzz. He actually shut the engine down around the time they touched down, however the speed of the dust and the targetory still would have prevent it from lnding in the pads.

From the ALSJ

102:45:40 Aldrin: Contact Light.

[The probes hanging from three of the footpads have touched the surface. Each of them is 67 inches (1.73 meters) long. The ladder strut doesn't have a probe.]
[Aldrin - "We asked that they take it off."]

[Journal Contributor Harald Kucharek notes that Apollo 11 photo S69-32396, taken on 4 April 1969, shows Eagle with a probe attached to the plus-Z footpad. This indicates that the probe was removed after that date. The probe attachment is highlighted in a detail.]

[Apollo 11 photograph AS11-40-5921 shows the area under the Descent Stage. A gouge mark made by the probe hanging down from the minus-Y (south) footpad is directly under the engine bell, a graphic demonstration that the spacecraft was drifitng left during the final seconds.]

[Armstrong, from the 1969 Technical Debrief - "We continued to touchdown with a slight left translation. I couldn't precisely determine (the moment of) touchdown. Buzz called lunar contact, but I never saw the lunar contact lights."]

[Aldrin, from the 1969 Technical Debrief - "I called contact light."]

[Armstrong, from the 1969 Technical Debrief - "I'm sure you did, but I didn't hear it, nor did I see it."]

102:45:43 Armstrong (on-board): Shutdown

102:45:44 Aldrin: Okay. Engine Stop.

[Neil had planned to shut the engine down when the contact light came on, but didn't manage to do it.]
[Armstrong, from the 1969 Technical Debrief - "I heard Buzz say something about contact, and I was spring-loaded to the stop engine position, but I really don't know...whether the engine-off signal was before (footpad) contact. In any event, the engine shutdown was not very high above the surface."]

[Armstrong - "We actually had the engine running until touchdown. Not that that was intended, necessarily. It was a very gentle touchdown. It was hard to tell when we were on."]

[Aldrin - "You wouldn't describe it as 'rock' (as in, 'dropping like a rock'). It was a sensation of settling."]

[Some of the other crews shut down 'in the air' (meaning 'prior to touchdown') and had a noticeable bump when they hit.]

[Aldrin - (Joking) "Well, they didn't want to jump so far to the ladder."]

[Readers should note that, although the Moon has no atmosphere, many of the astronauts used expression like 'in the air' to mean 'off the ground' and, after some thought, I have decided to follow their usage.]

[Armstrong, from the 1969 Technical Debrief - "The touchdown itself was relatively smooth; there was no tendency toward tipping over that I could feel. It just settled down like a helicopter on the ground, and landed."]

edited for spelling.

[JayUtah]

If that's trolling, then heaven help us.

That's not trolling. What is trolling is repeatedly stating your beliefs over and over again with the implication that they should be considered objective fact, while generally ignoring the content of objecting posts.

It aught to be made clearer that this is a board purely for those who positively believe that the moon landings are real, and that others are unwelcome.

Unsupported opinions and blind repetition are unwelcome. Disagreement is welcome, as long as it is well-reasoned disagreement. You are not being judged on the conclusion that you draw, but upon your methods for supporting that conclusion. You apparently haven't given much thought to what it takes to prove a conclusion. You've simply stated your conclusion and then called us closed-minded for not accepting it straight away without a suitable case made for it. Saying "It's obvious, and if you can't see it then you're just closed-minded," is not making a case.

It is not closed-minded to question a proposition that is offered. It is not closed-minded to put a hypothesis to the test. It is only closed-minded to reject a proposition without examining it on its merits.

We examined your claims on their merits. To summarize:

The alleged wire-pull in the Apollo 16 footage: You gave no evidence of a wire. You merely inferred that a wire was used because it was your default conclusion, barring any other explanation. You were shown evidence for another explanation which you declined to discuss. You declined to satisfy your burden of proof vis-a-vis your indirect argument, therefore your argument fails on its merits.

Sibrel's Bible challenge to the astronauts: Your argument is based on the premise that the astronauts did take, or should have taken, Bart Sibrel's challenge at face value. We filled you in on additional information regarding Sibrel's history with the astronauts. That history provides an additional reason why the astronauts would not want to cooperate with Sibrel in any way. Your argument fails on its merits because its premise is disproved; you cannot distinguish between the possible reasons for not swearing on Bart's Bible.

Sibrel's statement regarding the lunar module: He gives no objective or scientific arguments to support his opinion. He merely states his opinion and suggests it should be universal. Opinions on such matters have evidentiary merit only when the person offering them is qualified to do so. Sibrel has no such qualifications, therefore his argument fails on its merits because the premise of expertise is unsatisfied.

Dust in the LM footpads: The premise of your argument was that dust should have landed in the footpads, driven there perhaps by the engine exhaust. We have shown that premise to be scientifically unjustified. Therefore your argument fails on its merits.

At every step we have examined your claims according to their merits and have concluded that they lack a foundation. That is not closed-minded. Being open-minded does not mean you accept every proposition that is offered. And these are not propositions for which sutiable ambiguity exists to compel a charitable suspension of judgment. These are questions that have definite right and wrong answers and so can be appropriately rejected even by the open-minded.

You tell us that you once believed Apollo was real, but have been convinced subsequently by evidence. In fact, every conspiracy theorist makes exactly the same claim. It is fashionable to claim one has been dragged kicking and screaming against his will to belief in the conspiracy theory, supposedly because the evidence for it is so strong. I generally disregard such claims because behavior speaks louder than words. If your belief in the moon hoax theory had really unfolded according to the above scenario, then it shouldn't be too hard to restore your faith in Apollo simply by pointing out the glaring errors in the hoax theory and the generally irresponsible and dishonest nature of the claims and claimants. It would show that your stated basis for belief isn't really as strong as you originally surmised. But in fact these supposed converts to conspiracism, yourself included, defend the conspiracy theory tooth and nail to the point of utter irrational defiance of contrary evidence.

You seem to have surveyed some common moon hoax theory sites, but you don't seem to have done much research on Apollo outside of that. You are letting these people decide what evidence you see and you are letting them determine your beliefs. If you wish us to believe you are truly open-minded and have approached the hoax theorists with an intellectual mindset instead of an ideological one, then you need to demonstrate your willingness to consider their claims critically and not just subscribe to them without further thought.

Nothing obliges us to accept poor arguments. If you cannot make a well-reasoned argument in support of your claims, then you cannot expect reasonable people to believe them.

[JayUtah]

There is considerable ongoing debate about the actual altitude of the Apollo 11 LM cutoff. I am aware of Armstrong's statement that he did not hear Aldrin's "contact" call and of his belief that the engine may have been running at touchdown. However, his confirmation of "engine stop" comes very quickly after Aldrin's call. The crew's statements are ultimately inconclusive and reflect some uncertainty about whether they had touched down prior to shutting off the engine.

The 16mm film apparently shows the LM coming to rest prior to the cessation of the dust sheet, but the surface is only slightly visible in the lower right corner of the video. Photos like AS11-40-5921 and AS11-40-5892 can be interpreted to suggest that the disturbance of the surface by the probes came after the plume erosion effects. -5892 is the most hotly debated, with some claiming that the apparent enlargement of the plume trench under the DPS skirt is due to fluid erosion while others claiming, on the basis of the other photo, that the enlargement is due to the buckling of the probe at that point.

The objective evidence and crew testimony agree that Eagle's DPS was shut down "at about the same time as Eagle touched down", but there will likely be no answer as to the precise sequence.

Apollo 11 may very well be an exception to the rule. In the nominal case we can be sure that the footpads and dust sheet never intersected in time and space. But in the Apollo 11 case we must consider the possibility that the footpads were low enough to intersect the dust sheet, regardless of whether they contacted the surface itself prior to engine cutoff. In that case we would turn our attention to the kinetic energy of these entrained particles. Dust disturbed by the engine would not "settle". Particles briefly entrained in an Earth enviroment become aerosols rapidly after the entrainment no longer dominates. Aerosolization is not possible in the lunar environment. Thus there are no low-velocity possibilities for entrained lunar dust, either during or after entrainment. Dust particles striking the solid surfaces of the landing gear would naturally rebound with considerable energy in mostly elastic collisions. This is not consistent with their staying in the vicinity of the footpads.

[PhantomWolf]

So in English, what you mean is that if the pads did drop into the moving dust sheet while the engine was going, the exhust would have made all the dust caught in it move at such a speed that any hitting the pads would have just bounced off the pad covering and landed a fair distance away rather than just drifting down onto the top of the pad itself because there's no air to hold the dust up and stop the motion.

[margamatix]

But Cernan said that the dust got everywhere including folds of the spacesuit and all moving parts. So how did it get there? Either dust behaves as dust, or it doesn't.

[gdwarf]

margamatix said:

But Cernan said that the dust got everywhere including folds of the spacesuit and all moving parts. So how did it get there? Either dust behaves as dust, or it doesn't.

Kicked up by sheels, by kicking dust, by falling down onto dust, he never mentions dust on the lander, but in the space suits/rover, it makes sense for it to be there.

[JayUtah]

But Cernan said that the dust got everywhere including folds of the spacesuit and all moving parts. So how did it get there?

Watch the film and look at what Cernan does to get it there.

Either dust behaves as dust, or it doesn't.

Why does that equate to dust behaving the same way under two completely different sets of circumstances?

Hopping around in your cloth-covered suit and kicking dust upward, kneeling down it in, and picking up dust-covered samples to stow in your PLSS bag will definitely deposit dust all over you. That's utterly unlike dust being sandblasted away at 2,500 meters per second and not sticking to smooth, hard surfaces.

Consider also that the suit's outer layer is highly porous, like regular cloth. Have you seen a real Apollo suit? It would be impossible to keep that clean. It will attract, retain, and show dust even under the most careful circumstances. How do you make bone-dry dust stick to aluminum? To Kapton?

I don't agree with your presumption that because dust behaves one way in one circumstance, it should therefore behave identically in all other circumstances. You're just telling us that, "Dust is dust," but that's a cop-out. It's slightly better than begging the question, but not much better. We've given you an argument based on the precise details and differences in the two scenarios. You can't argue that away with a vague, general handwaving.

[RAF]

margamatix said:

Either dust behaves as dust, or it doesn't.

The Moon is not the Earth. Conditions are different, ie. the Moon lacks an amosphere. Dust simply does not behave in the same manner as it does on the Earth.

[JayUtah]

Dust simply does not behave in the same manner as it does on the Earth.

Specifically it does not billow and settle.

In the case of the LM engine, you have fluid entrainment. I've discussed that at length. Where fluid entrainment exists, all other considerations are second-order.

In general dust will behave ballistically. It does not aerosolize.

Dust will also respond to electrostatic attraction and repulsion. Suit motion generates a great deal of electrostatic charge, especially since its outer layer is Beta cloth. Where dust is disturbed ballistically (e.g., footsteps, sampling), a particle may be captured electrostatically from its ballistic path. Dust particles entrained in an exhaust plume have far too much kinetic energy to be captured electrostatically.

The films consistently show astronauts making contact with "dirty" objects -- tools, rock samples, hands, the surface itself -- using all parts of their suits. It is not surprising that the dust got everywhere.

[RAF]

jayutah said:

It does not aerosolize.

Ah yes...that was the word that was on the tip of my tongue, yet did not make it to the page.

And speaking of electrostatic charges, this page describes "levitating Moon dust". Another example of differences in dust behavior between the Earth and the Moon.

[JayUtah]

The lack of atmosphere makes electrostatic attraction a more dominant effect than on Earth. In an atmosphere electrostatic discharge can slowly dissipate. Charged particulates in a vacuum will retain their electrostatic charge for longer and therefore be more susceptible to attraction. This was a problem for camera lenses. The grinding of film through them created a static charge that attracted dust to the lens. The attraction was not strong enough to pull dust generally from the ground. But it could pull dust from the space suits, and from ballistic trajectories initiated by footsteps, rover skids, etc.

Aerosolization is where fluid entrainment in turbulence dominates gravity. That's a fancy way for saying that "dust gets everywhere", but for atmospheric purposes and not necessarily in a way that applies to this argument. I do not doubt that Cernan said dust gets everywhere, but it was not because of aerosolization. It was because of the effects I already detailed. Those effects are dominated quite forcefully -- by several orders of magnitude -- by fluid entrainment in the case of exhaust plume effects.

[JayUtah]

Oh, and obviously the atmosphere provides a resistant fluid medium through which charged particulates must travel in order to respond to electrostatic attraction.

[bazbear]

margamatix said:

I believed for over 30 years that we did land on the moon and it is only the weight of evidence I have seen that convinced me that I was wrong. You can hardly say I have a closed mind.

I will continue to look objectively at any site to which I am directed by forum members, but none I have seen so far comes within a million miles of being "proof"

I can't imagine what would ever be proof enough for you.

[Count Zero]

bazbear said:

I can't imagine what would ever be proof enough for you.

That was addressed here on reply #19. I called his bluff, but he hasn't said whether he'll go for it.