Merged Apollo "hoax" discussion - continuation thread

[jaydeehess]

"About a year ago, billionaire Jeff Bezos went to NASA with plans to recover some of the F-1 engines that helped power Apollo astronauts beyond Earth orbit in the late 1960s and early 1970s."

http://www.edn.com/electrical-engin...o-engine-treasures-recovered-from-ocean-floor

-LF

Saw this on the news last night. Historical find, kudos to the people involved.

 

[Dcdrac]

what a ride what a ride

https://www.youtube.com/watch?v=wvWHnK2FiCk

https://www.youtube.com/watch?v=k_OD2V6fMLQ&feature=endscreen&NR=1

 

[Belz...]

Unfortunately, it seems to be all too frequent (and not just in space images). The CTers don't understand image compression, image artefacts (either in general or JPEG in particular), or any sort of photogrammetry.

They also don't understand exposure.

 

[cjameshuff]

They also don't understand exposure.

Or computer renderings of elevation maps.

That's a color overhead photo, badly overcompressed with JPEG, stretched over a triangle mesh generated from an elevation map, rendered from the side, and then JPEG'd again. All sorts of artifacts for CTs to zoom and color shift into view.

 

[Willy Ekerslike]

"Three categories of samples were brought back by the Apollo 11 crew: contingency, bulk, and documented (or core) samples. Neil Armstrong collected contingency samples first - about one kilogram of surface material - being careful to get far enough away from the lunar module that the soil would not have been contaminated by the residue from the descent engine exhaust. He sealed this sample in a plastic bag."

Yes, of course this would be the only way to do it. Seems logical to me- oops- I used the 'L' word. Darn.

 

[CORed]

They also don't understand exposure.

The nonsense about no stars makes that pretty clear. I strongly suspect none of these people have actually done any photography, or at least none beyond the "point and shoot" level.

 

[nomuse]

Wait a minute...his idea that the lunar samples would have been contaminated by the LM exhaust leads him to the conclusion that "The rocks must have been tampered with?"

How does this work in conspiracy-land anyhow? The Apollo missions take place, the conspiracy realizes there is some surface contamination on their samples that supports their story, so they use some kind of sooper sekret "radiation oven" to dry them out without changing their chemistry at all and THEN release them to geologists?

So the conspiracy goes through all this effort to create an inconsistency?

 

[Call Me Crazy But]

As a quick aside, Quest (Freeview 38) are showing the Mythbusters Apollo episode tomorrow - Tuesday at 8.00. Thought I'd mention it as I don't think it's been shown in the UK before. At least not on free-to-air.

 

[nomuse]

Well, there is a possible defense for the usual hoaxie line of argument.

It follows like this;

(The operation) is quite technical/complex. (This inconsistency) is subtle/unknowable at the time of the hoax, so it is possible the conspiracy made a mistake and omitted/committed it. Fortunately I am a brilliant Google U. polymath and I was able to deduce what none of the professionals working at the time, or since, had managed to anticipate or realize.

You can see the obvious flaw, of course. The reasoning may be sound, but it is based on an erroneous assumption. The inflated opinion of their own skills is pure Dunning-Kruger.

 

[Bill Thompson]

I overestimated human intelligence. That was my mistake. I thought everyone knew that we went to the moon and that people who pretended to think we did not were just joking.

So I sent a private email, as a joke to the owner of an Apollo Hoax forum. He instantly made the email public because it was exactly what the hoax believers had been praying for.

Now, no matter how many emails I send them to tell them it was a lark, they still do not believe me.

Google "William M Thompson Apollo Hoax"

Here was my idea. All these people claim that apollo landing is a hoax. So why doesn't anyone come forward who was an engineer with Apollo? So wouldn't it be funny if I pretended to be some old guy on his death bed who was involved in the hoax.

The results were amaizing. I suddenly had offers to appear on the radio and television and write a book. I told them all it was a joke. It still does not stop the fact that believers quote me to this day.

You can also just go here and search for "William M. Thompson" http://en.metapedia.org/wiki/Moon_Hoax
I still think it is funny. Sorry, my twisted sense of humor.

 

[abaddon]

I overestimated human intelligence. That was my mistake. I thought everyone knew that we went to the moon and that people who pretended to think we did not were just joking.

So I sent a private email, as a joke to the owner of an Apollo Hoax forum. He instantly made the email public because it was exactly what the hoax believers had been praying for.

Now, no matter how many emails I send them to tell them it was a lark, they still do not believe me.

Google "William M Thompson Apollo Hoax"

Here was my idea. All these people claim that apollo landing is a hoax. So why doesn't anyone come forward who was an engineer with Apollo? So wouldn't it be funny if I pretended to be some old guy on his death bed who was involved in the hoax.

The results were amaizing. I suddenly had offers to appear on the radio and television and write a book. I told them all it was a joke. It still does not stop the fact that believers quote me to this day.

You can also just go here and search for "William M. Thompson" http://en.metapedia.org/wiki/Moon_Hoax
I still think it is funny. Sorry, my twisted sense of humor.

According to the link, you died in 2002. I wept.

 

[threadworm]

And just so we can expose our lovely new friend's complete lack of ability to do basic research some more, a tiny amount of googling reveals that the Clementine probe in the late 90s also discovered evidence of water, the Russians discovered water in their lunar samples in 1976, and this paper:

http://adsabs.harvard.edu/full/1970GeCAS...1.1103F

discusses the Apollo 11 samples. It has this to say:

"We do not think that the lower water content of the vacuum-sealed sample indicates large scale contamination by terrestrial water in the other sampels because there appears to be great variability in water content between two pieces of the same breccia that had been exposed to the terrestrial atmosphere for several months."

"Contamination with unexpended rocket fuel dumped on the lunar surface can be ruled out"

and

"Additions of rocket exhaust gases cannot be as easily determined as can those of organic fuel, and these gases still remain a possibility as a contaminant...the CO2 results discussed later, however, tend to rule out rocket exhaust contamination."

So, not only was water found in Apollo 11 samples, and reported in the scientific literature, but its sources (including the possibility of rocket exhaust contamination) were considered.

E2A: And we can use studies like this COSPAR to show that contamination by LM exhaust products was anticipated and well studied long before a lunar module got near the moon, and they could therefore be allowed for in any examination of lunar samples.


Next...

 

[threadworm]

Dammit!

I was mid-post!!

In summary, my point was: 5 miles doesn't matter. 10 miles doesn't matter. 2 people knew exactly where they were, and the signal to and from the LM was good enough to speak to the people they needed to.

The idea that not being able to locate them to within a few feet matters is nonsense. A positional error of 0.23% (5 miles as a % of the moon's diameter) over 240000 miles is pretty good going in my book.

 

[Anders Lindman]

I have already posted this in the past, but it could be worth repeating: why haven't any new close-up photos been taken of the moon's surface since the early 70s?!

Probably because the moon landscape in reality doesn't look black and white like in the Apollo photos. Haha.

 

[Jim_MDP]

I have already posted this in the past, but it could be worth repeating: why haven't any new close-up photos been taken of the moon's surface since the early 70s?!

Probably because the moon landscape in reality doesn't look black and white like in the Apollo photos. Haha.

LOL wut?

It's too early to be that high.

 

[LaurelHS]

The Moon landscape isn't black and white in all of the Apollo photos. There was a greenish-coloured boulder at one of the Apollo 15 sites and the Apollo 17 crew found a patch of orange soil.

 

[R.A.F.]

I have already posted this in the past, but it could be worth repeating: why haven't any new close-up photos been taken of the moon's surface since the early 70s?!

Nope...wasn't worth repeating...

 

[smartcooky]

Jay

But for landing on the Moon, the landing programs have a specific task. They are supposed to manage the state vector, using engine thrust and direction as their inputs, so that the location portion of the state vector coincides with the desired landing point at the same time the lateral velocity component of the state vector is zeroed out and the vertical component is less than a certain value. A lot of calculus goes into determine what path and velocity states best accomplish that. But in the dirty details the system works out to be a series of basic, simple control laws.

In essence this looks very similar my understanding of how the "back end" of an inertial navigation system works, where the X, Y & Z vectors are are provided by the "front end" containing highly accurate accelerometers.

In the case of the Apollo navigation system, the "front end" is a computer that calculates the X, Y and Z vectors using the fact that a given thrust in a given direction will result in a known acceleration? By knowing the starting point, and knowing the exact acceleration, it is possible to accurate calculate, in real time, exactly where the spacecraft is in 3D space relative to that starting point.

Is that a fair assessment?

 

[JayUtah]

Is that a fair assessment?

Not really. Spacecraft guidance uses measured (not assumed) acceleration too.

In accelerated flight, the guidance system integrates measurements from the accelerometers on the IMU. So when the engine is on, the RCS is operating, etc., the guidance system additionally integrates measured acceleration into the state vector. You don't assume some engine will produce nominal acceleration. You simply measure the acceleration that is actually produced.

In unaccelerated flight the state vector is updated by means of a gravitation model of some sort. For Earth orbit, lunar orbit, cislunar cruise, and all the other major modes, there is a gravitational model that updates the state vector based on a parameterized gravity (i.e., orbital) model.

For example, the state vector at engine cutoff for an insertion maneuver uniquely determines the orbit. Position and velocity vector, relative to the primary, determine the orbital elements about that primary. From then on, the state vector can be updated from the generalized orbit model -- at time t along some orbit O, position and velocity are given by equations in the orbital model.

Obviously the initial orbit is only as accurate as the accumulated state vector when the insertion completes, which is why ground calibrations are necessary. If you enter an orbit around the Moon and leave the engine alone, each AOS/LOS pair goes into a numerical model of the orbit and after about 10 revs in the orbit you have a very highly accurate concept of the orbital elements. This can be uploaded to the spacecraft, which can then very accurately update its state vector in unaccelerated flight by solving the orbit at a time resolution most appropriate to the need.

Orbit calibrations are part of practically every space mission. We use various observational techniques on the ground to empirically determine the orbit a spacecraft has entered, then we can plan accelerated flight accordingly.

 

[smartcooky]

Not really. Spacecraft guidance uses measured (not assumed) acceleration too.

In accelerated flight, the guidance system integrates measurements from the accelerometers on the IMU. So when the engine is on, the RCS is operating, etc., the guidance system additionally integrates measured acceleration into the state vector. You don't assume some engine will produce nominal acceleration. You simply measure the acceleration that is actually produced.

In unaccelerated flight the state vector is updated by means of a gravitation model of some sort. For Earth orbit, lunar orbit, cislunar cruise, and all the other major modes, there is a gravitational model that updates the state vector based on a parameterized gravity (i.e., orbital) model.

For example, the state vector at engine cutoff for an insertion maneuver uniquely determines the orbit. Position and velocity vector, relative to the primary, determine the orbital elements about that primary. From then on, the state vector can be updated from the generalized orbit model -- at time t along some orbit O, position and velocity are given by equations in the orbital model.

Obviously the initial orbit is only as accurate as the accumulated state vector when the insertion completes, which is why ground calibrations are necessary. If you enter an orbit around the Moon and leave the engine alone, each AOS/LOS pair goes into a numerical model of the orbit and after about 10 revs in the orbit you have a very highly accurate concept of the orbital elements. This can be uploaded to the spacecraft, which can then very accurately update its state vector in unaccelerated flight by solving the orbit at a time resolution most appropriate to the need.

Orbit calibrations are part of practically every space mission. We use various observational techniques on the ground to empirically determine the orbit a spacecraft has entered, then we can plan accelerated flight accordingly.

So it uses a combination of assumed accelerations and velocities and actual measurements of same?

It sounds like the old "suck it and see" approach; you put the spacecraft into what you think is a particular orbit, then observe it to see how far away from the intended orbit it actually is, then adjust the orbit to make up the difference.

It reminds me of a funny story I once read on an ASW course back in the 1980's


"The missile knows where it is because it knows where it isn't. By subtracting where it is from where it isn't, or where it isn't from where it is (depending on which is the greater) it obtains a difference, or deviation.

The guidance system then uses this deviation to generate corrective commands to drive the missile from a position where it is, to a position where it isn't. Consequently, the position where it is now is the position where it wasn't, and it follows that the position where it was, is now the position where it isn't.

In the event that the position where it is now is not the position that it previously wasn't, the system will have acquired a variation, being the difference between where the missile is and where it wasn't.

If the variation is considered to be significant, it may be corrected, however, the missile must also know where it was. The missile guidance sequence can be summarised as follows;

Because a variation has modified some of the information the missile has obtained, it is not sure where it is, however, it is sure where it isn't and it knows where it was. It now subtracts where it should be from where it wasn't, or vice-versa, and by differentiating this from the algebraic sum of where it shouldn't be, and where it was, it is able to obtain both the deviation and its variation."