Lost Bird Proves Apollo Inauthenticity

[scooter]

altitudes and azimuths...okaaayyy.
I think echnaton is probably right...this is becoming a polluted forum.

[lukepemberton]

Jul 7, 2011 16:50:15 GMT -4 fattydash said:

Precise determinations of altitudes and azimuths of celestial objects should do it Bob. They had the equipment for this and the human talent to boot, Aldrin manning the scope, sextant. I imagine they could have determined their position with great position

Sorry, did not mean to discount your question, I was checking out that video. Wild!

I think twik wants you to answer the question posed at post number 11 of this thread.

[drewid]

Barnard's star has an altitude of approximately 6 light years, is that accurate enough?

[ka9q]

Radio communications is both my hobby and my profession. Navigation by radio is closely related to communications by radio, so I also know a fair bit about it including how Apollo and other spacecraft are navigated. And I can say that fattydash is completely off base with his allegations -- which by now should surprise no one.

I should explain how Apollo was tracked. Integral to the Apollo Unified S-Band (USB) communications system was the ability to continuously measure range (the distance between the tracking station and the spacecraft) and range-rate (the component of relative velocity along the spacecraft-station line) with respect to the active earth tracking station. This was determined to extreme precision: a few meters and a few cm/sec, respectively.

It's important to understand that simply knowing the range is insufficient to unambiguously fix the position of the spacecraft. It could be anywhere on a sphere centered on the tracking station with a radius equal to the range. More is needed.

When this system tracked a spacecraft in earth orbit or in cislunar space (just a highly eccentric earth orbit), a time series of range and range-rate measurements were fed into a computer model with several important components:

1) A mathematical model of the earth's orientation in space as a function of time, i.e., the directions of its poles, its angular rotation rate and the position of the prime meridian at a certain epoch. Given the time of day, this allows coordinates with respect to the rotating earth to be converted into inertial (non-rotating) earth-centered coordinates and vice versa. For example, the inertial position of a tracking station could be computed as a function of time.

2) A highly accurate survey of each ground tracking station antenna.

3) A detailed model of the earth's gravity field. The earth's mass is not uniformly distributed around its center of mass; it has a highly pronounced equatorial "bulge" due to its spin plus other smaller but still important irregularities. This causes the direction and magnitude of the earth's gravity to depend on latitude and longitude as well as altitude. These models are determined from the tracking of many earth satellites over many years.

Since gravity is the dominant force on an earth-orbiting spacecraft, this model is crucial to the whole system.

4) Models of the positions of the sun, moon and other planets relative to the earth, and estimates of their masses.

5) A highly accurate clock to tag the ground stations' ranging measurements.

The mathematical model accepts a time series of range and range-rate measurements and, making the critical assumption that no external forces other than gravity are acting on the spacecraft, uses Newton's equations of motion to find the 3D position and velocity of the spacecraft at a chosen "epoch" time that best fits all the observations when run forward and backward in time. The fit is never exact because of "noise" in the measurements so the system is solved in a "least squares" sense.

The resulting 3D position and velocity vectors at a given time are known as "state vectors". They are periodically loaded into the spacecraft computers where they can be propagated (carried forward in time) with local computer models of gravity and measurements of rocket thrust, if any.

This system proved very accurate with spacecraft orbiting the earth. The moon was a different story. Tracking a moon-orbiting spacecraft all the way from earth required several more mathematical models:

6) A lunar "ephemeris": the position and velocity of the moon's center of gravity with respect to the earth over time, its rotation rate, polar orientation, and prime meridian location.

7) A model of the moon's gravity field. This was the weak link in the chain; it was known far less accurately than the earth's gravity field. As with the earth's gravity field this was determined by tracking spacecraft in lunar orbit. But there had only been a handful of such spacecraft by Apollo 11 and it was impossible to track any of them when they were behind the moon. So the lunar gravity field model was especially inaccurate on the far side.

The end result of all this is that only an approximate orbit and landing location could be immediately determined for Apollo 11's Eagle. In fact, the inaccurate lunar gravity model is the likely culprit for Eagle having overshot its intended landing spot.

I can hear 'fattydash' saying "How could Eagle possibly have landed and returned to Columbia given all this inaccurate tracking?"

Good question. The short answer was that absolute accuracy was not nearly as important as relative accuracy. Eagle had a landing radar that provided accurate measurements of altitude and velocity with respect to the moon. This was a critical piece of equipment for the actual landing, as the radio-tracking-based estimates were then typically several thousand feet off -- much too great when you need to know your altitude to a few feet or less. But it's important to remember that the landing radar could not determine -- nor did it need to determine -- the LM's absolute position on the moon.

To facilitate rendezvous Eagle and Columbia had several ways to track each other. Eagle had a rendezvous radar (the dish on top of its "nose") that operated through a transponder on Columbia. As a backup, Columbia could measure range and range rate to Eagle through the VHF voice radios, albeit less accurately than Eagle's rendezvous radar. And they could sight each other through the same optical instruments used to align the inertial reference platform.

It's important to understand that these were relative measurements. Eagle and Columbia could determine their positions relative to each other far more accurately than either could determine its position relative to the moon. But accurate relative measurements are what count in rendezvous.

So the Eagle was hardly "lost" when it landed. Its approximate landed location was immediately determined by means of earth tracking and the on-board navigation system, but the absolute accuracy of these estimates was too poor to enable Collins to sight Eagle from orbit, or for the laser ranging stations on earth to quickly locate the Apollo 11 LRRR. Eventually, Eagle's exact landing site was accurately determined by analysis of the movie film taken during the descent and this enabled the lunar ranging observatory to find the reflector. But this obviously had to wait until the film could be returned to earth, processed and analyzed.

Yet another red herring from the hoax crowd goes up in flames.

[fattydash]

This is by a light year my best thread yet. Of course it should not be closed. It is by a light year Apollo's most promising solution.

I supplied a response to #11. The astronauts may determine their position by making multiple azimuth and altitude measurements of celestial bodies. They for example may call the sun's azimuth zero degrees, and then all measurements are to be made with the sun as reference.

[fattydash]

To proceed, on the morning of 07/21/1969 at 02:39 UTC, when Armstrong climbs out of the ship, the LM, the firmament will have a characteristic fingerprint/star print/venus print. The stars, venus, sun, can only be in those places at that time at Tranquility Base's precise location.

Lunar module pilot Aldrin has the requisite ability to take those measurements using his high precision instruments, scanning scope, sextant and in this way, Eagle's position may be identified, and precisely so. The precision of the instruments will determine the degree to which the Lick Observatory people will need to hunt for the LM. But to be sure, they would I imagine do quite well.

[ka9q]

So, fattydash, have you performed the error analysis calculations to show how errors in these various measurements (celestial object sightings, etc) would affect their determined position?

Have you compared them to the accuracy requirements of the laser ranging observatory? Do you even know what those requirements are?

If so, let's see them.

If not, then withdraw your assertion that this would have been sufficient.

[fattydash]

And so the "solution" to the great Apollo Hoax lies here. Astronauts Aldrin and Armstrong should have taken measurements of the positions of celestial bodies and these positions would be "matched" to that unique place on the lunar surface which at that time; 07/21/1969 at 02:39 would have such features. Those azimuths measured, those exact altitudes measured, with the sun for reference at azimuth zero degrees.

The LRRR people would be called, the reflector would be targeted based on the coordinates determined by the aforementioned measurements and Tranquility base and the astronauts would be found.

As they did not do this, follow the obvious, appropriate course of actions under the circumstances, as they did not want to be found as based upon their behavior, their not following the very simple procedure as above, the Apollo 11 astronauts decidedly were not at Tranquility Base. they were not on the moon, as after all, who wants to be lost on the moon?

[ka9q]

Here's just one example of an error source that would affect the accuracy of a surface position calculation through optical sightings of celestial objects.

I've already explained that the moon's gravity field is both highly irregular and, during Apollo, not accurately known. Not only does this cause inaccuracies when propagating a state vector, it also causes inaccuracies in any optical sightings taken from the surface using the local gravity vertical as a reference.

If I set up an ordinary plumb-bob and asked you the direction it points, you would most likely answer "toward the center of the earth, obviously!" This answer would be wrong. It points somewhat away from the center of the earth for two reasons: the earth is rotating, and the earth's mass is not uniformly distributed. Although the moon turns only 1/28 as fast as the earth, its internal mass distribution is even more irregular than the earth's. And since the exact nature of this distribution was not known during Apollo, even simple optical surveying-type measurements from the surface would not have been accurate.

[fattydash]

As stated, this is my best thread so far by a parsec. It would be an absolute pity to lock it.

I realize the concerns of many given what I seem to have stumbled upon here. Everyone should take a deep breath including myself for obvious reasons.

I have been up for a long time working at the hospital and writing to my Apollo Hoax colleagues. I realize this is not on topic, but since there was the unfounded request to lock the thread, I believe this appropriate.

Leave this be until I return. I must sleep. I am extremely fatigued from work. I trust all will be fair here.

I believe I answered Bob's query most thoroughly. The position of the Eagle would be determined by taking azimuth and altitude measurements of multiple celestial bodies. The Eagle would be so located, and by way of the LRRR the astronauts would be found.

I promise to return and answer all questions posed. But I must sleep now.


Respectfully P

[Jason]

fatty, ka9q has demonstrated why the astronauts didn't need to get out their sextants in order to rendezvous with Colombia in #33. Can you point out where he is wrong?

And would it really be "simple" to use a sextant with one of those helmets on?

[trebor]

Jul 7, 2011 18:17:39 GMT -4 fattydash said:

I believe I answered Bob's query most thoroughly. The position of the Eagle would be determined by taking azimuth and altitude measurements of multiple celestial bodies.

Perhaps you should try reading the responses to it.
Especially those by ka9q

[Bob B.]

Jul 7, 2011 16:01:58 GMT -4 @fatty dash said:

Hey Bob, check out this MIT video, search, "Computer for Apollo 1965"-science reporter TV series. the MIT eggheads claim the sextant-computer system can determine position. your thoughts? thanks!

The LM wasn't equipped with a sextant; only the CM had that. The LM had an Alignment Optical Telescope (AOT) only, which was used for alignment of the inertial platform. Furthermore, the AOT read angles to a precision of only 0.02 degrees, which is insufficient to provide the accuracy you think the LM was capable of.

EDIT

Sighting on Earth features as described in that video from the distance of the Moon with an angle accuracy of only 0.02-degree gives a position error of +/– 134 kilometers. Even if they could interpolate to an accuracy of 0.01-degree, that still means they couldn’t measure position any better than +/– 67 km. The position of the LM was already known to far greater accuracy than this. The error ellipse for landing was something like +/– 8 km east-west and +/– 2 km north-south of the target point, and the LM landed within this ellipse, though long of the target.

[twik]

Fattydasher, here's what my question in post 11 was:

"So, fattydasher, you are conceding that the Eagle was actually there, near the Moon? That they actually sent *something* up? "

This is not a trick question, I'm trying to be sure I understand what you say happened. There was no mention of altitude, attitude or azimuth in my question.

[scooter]

Jul 7, 2011 19:00:15 GMT -4 Bob B. said:

Jul 7, 2011 16:01:58 GMT -4 @fatty dash said:

Hey Bob, check out this MIT video, search, "Computer for Apollo 1965"-science reporter TV series. the MIT eggheads claim the sextant-computer system can determine position. your thoughts? thanks!

The LM wasn't equipped with a sextant; only the CM had that. The LM had an Alignment Optical Telescope (AOT) only, which was used for alignment of the inertial platform. Furthermore, the AOT read angles to an accuracy of only 0.02 degrees, which is insufficient to provide the precision you think the LM was capable of.

EDIT

Sighting on Earth features as described in that video from the distance of the Moon with an angle accuracy of only 0.02-degree gives a position error of 134 kilometers. Even if they could interpolate to an accuracy of 0.01-degree, that still means they couldn’t measure position any better than 67 km. The position of the LM was already known to far greater precision than this. The error ellipse for landing was something like +/– 8 km east-west and +/– 2 km north-south of the target point, and the LM landed within this ellipse, though long of the target.

Nice work, Bob B.
Somehow I think fatty will not get it, and keep on with his azimuth and altitude (sic) thing...oh well, he's in his happy place it seems...quite pleased with himself.