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51

The Hoax Theory / Re: Telematry Data

« Last post by benparry on November 03, 2024, 01:31:17 PM »

NASA Goddard is the typical repository for NASA's space data. But I don't know what Apollo telemetry records they might have, or in what form they're in, or how easy it is to access it.

Telemetry is really boring. Except for historically significant cases like Apollo 13, there is almost no historical value after the mission or program is complete. Yes, incurable nerds like me like to have it. But it means almost nothing to anyone else. Telemetry is literally just streams of numbers divided into different logical channels. When you graph those numbers, you have a picture of one parameter of spacecraft operation over time—say, oxygen tank pressure. It's absolutely vital if you're trying to diagnose a failure in the spacecraft. But after the mission is over, the crew is home safely, and the spacecraft has either burned up or been gutted and sent off to the Smithsonian, those paper strip charts or computer tapes have very limited appeal. After the program ends and you don't fly that spaceship model anymore, there's not even really any technical need for raw telemetry.

What makes Apollo 11 special for telemetry is that one of those streams of numbers was the raw video signal from the jury-rigged television system. That wasn't part of the original telemetry design. Nowadays we're accustomed to live 4K digital video from ascending launch vehicles. But in 1969, video embedded in a telemetry stream wasn't really standard thinking. They had a long-term plan for live television from the lunar surface, but it went entirely differently and needed either the big erectable antenna or the high-gain antenna on the rover. Beginning with Apollo 12, the telemetry stream went back to simply reporting cabin temperature, fuel cell power output, spacecraft attitude, and so forth. Just boring streams of numbers representing engineering measurements. The TV signal came in over a different carrier.

Ah ok cool thanks again Jay. Once again your the font of all haha

52

The Hoax Theory / Re: Telematry Data

« Last post by JayUtah on November 03, 2024, 01:13:48 PM »

NASA Goddard is the typical repository for NASA's space data. But I don't know what Apollo telemetry records they might have, or in what form they're in, or how easy it is to access it.

Telemetry is really boring. Except for historically significant cases like Apollo 13, there is almost no historical value after the mission or program is complete. Yes, incurable nerds like me like to have it. But it means almost nothing to anyone else. Telemetry is literally just streams of numbers divided into different logical channels. When you graph those numbers, you have a picture of one parameter of spacecraft operation over time—say, oxygen tank pressure. It's absolutely vital if you're trying to diagnose a failure in the spacecraft. But after the mission is over, the crew is home safely, and the spacecraft has either burned up or been gutted and sent off to the Smithsonian, those paper strip charts or computer tapes have very limited appeal. After the program ends and you don't fly that spaceship model anymore, there's not even really any technical need for raw telemetry.

What makes Apollo 11 special for telemetry is that one of those streams of numbers was the raw video signal from the jury-rigged television system. That wasn't part of the original telemetry design. Nowadays we're accustomed to live 4K digital video from ascending launch vehicles. But in 1969, video embedded in a telemetry stream wasn't really standard thinking. They had a long-term plan for live television from the lunar surface, but it went entirely differently and needed either the big erectable antenna or the high-gain antenna on the rover. Beginning with Apollo 12, the telemetry stream went back to simply reporting cabin temperature, fuel cell power output, spacecraft attitude, and so forth. Just boring streams of numbers representing engineering measurements. The TV signal came in over a different carrier.

53

The Hoax Theory / Re: Telematry Data

« Last post by JayUtah on November 03, 2024, 12:40:41 PM »

That kind of information is usually hand waved away by hoax proponents.

Of course. They want simple(r) answers that appeal to their intuition. I say "simpler" because conspiracism is all about believing you're smarter than the sheeple without making the full effort to become genuinely smart. Conspiracy theories are a shortcut to the illusion of erudition, the shady side of "true crime" and armchair detectives. The scenario in their minds is, "NASA tried really hard to put one over on me, but I figured it out when they admitted they don't have the originals: if they did, it would reveal the hoax." And so forth. They can pretend they're smarter or more clever than the average Joe who just accepts what NASA tells them. But then when faced with the full, non-simple set of facts for any given situation, they don't want to hear it. It's all about creating a world in which they're the hero, not about finding what's actually true according to the facts—the often very non-simple facts.

There are scientific facts like the radiation environment in space. The conspiracy theories talk about the "searing radiation hell" of cislunar space. That harks to the fears of Chernobyl and atomic warfare. But the physical facts of the Van Allen belts take a lot of effort to understand properly. They are extremely non-simple, but they are true. And yes, if you know them, you can chart a safe orbital course through the safer regions. Conspiracy theorists don't want to hear about that, first because it means they're wrong and second because it means they're not the smartest people in the room for "understanding" radiation better than the sheeple. You can't get around scientific facts. You either understand how the universe works or you don't. The universe doesn't respect ignorance.

And there are historical facts like having to cobble together something for only one mission to record a jury-rigged video signal in a way that would fit the mission profile and not compromise more important objectives. Intuition notwithstanding, there were those who didn't want to bother with lunar surface television broadcasts at all. It would complicate an already iffy mission for very little additional data-gathering value. Obviously more humanistic heads prevailed, but that still left a problem for which the best solution was a one-off technical compromise.

Historical facts are still facts; something factually happened. But unlike the manifest state of the universe, historical occurrence is governed by people making decisions—often not wisely and often under pressing or untidy circumstances. There is no objective observation against which to measure their propriety. Hence history is full of compromises, and serious historians make it their job to understand such impurities without judgment or suspicion. Conspiracy theorists, on the other hand, interpret every departure from simplistic armchair expectations as evidence of wrongdoing or deception. They presume (wrongly) that anything that actually happened should have happened the obvious and logical way their intuition and hindsight dictate. These arguments land better with an unsophisticated audience precisely because intuition is powerful and history is messier than we often care to admit.

54

The Hoax Theory / Re: Telematry Data

« Last post by benparry on November 03, 2024, 12:26:58 PM »

As with most hoax topics i wonder why this information isn't given out by people when they debate this kind of stuff.

It is though. What generally happens is excuses are made or the information is simply ignored. One of the things I like to do in discussion threads about the 'missing' telemetry data is to drop random bits of telemetry detail/data/graphs/reports in the comments, which is usually around then when you realise that most HB's aren't actually aware of what telemetry is.

Interesting. Do you have this data stored locally or is there an online resource

55

The Hoax Theory / Re: Telematry Data

« Last post by benparry on November 03, 2024, 12:26:31 PM »

That kind of information is usually hand waved away by hoax proponents.

Exactly which is why i wanted to get the facts. As usual Jay is the master haha

56

The Hoax Theory / Re: Telematry Data

« Last post by TimberWolfAu on November 03, 2024, 04:20:36 AM »

As with most hoax topics i wonder why this information isn't given out by people when they debate this kind of stuff.

It is though. What generally happens is excuses are made or the information is simply ignored. One of the things I like to do in discussion threads about the 'missing' telemetry data is to drop random bits of telemetry detail/data/graphs/reports in the comments, which is usually around then when you realise that most HB's aren't actually aware of what telemetry is.

57

The Hoax Theory / Re: Telematry Data

« Last post by Ranb on November 02, 2024, 06:19:53 PM »

That kind of information is usually hand waved away by hoax proponents.

58

The Hoax Theory / Re: Telematry Data

« Last post by benparry on November 02, 2024, 03:26:53 PM »

I think there's some confusion between what is considered original and what is considered backup. The Memorex telemetry tapes that were overwritten with new data were those from Apollo 11 and a bunch of other missions. These were the tapes running through the telemetry recorders during the Apollo missions and, as such, constitute the first recording of the data. That is the sense in which they could be considered originals. For Apollo 11, this also constituted the embedded television signal. Intuitively we would think of these as "originals" and therefore worthy of special protection. But the facts are slightly more complicated.

None of the data were directly usable from the tapes. To access the data on them, you needed telemetry tape machines, which were comparatively expensive and uncommon and most in demand for recording new data. You needed a technician to configure the heads and channel processors. This was especially true for the embedded video signal, which was a complete one-off used only on Apollo 11. You needed custom decoding hardware and technicians to operate it.

Therefore the first thing that was done with the telemetry was to read out the different data channels onto standard 9-track, 6250 bytes-per-inch computer tape or on paper strip charts. The charts can be read directly and photographically copied, and the standard computer tape could be run through any of the computers at NASA. For Apollo 11, the video signal was decoded and converted to a standard NTSC signal and recorded on standard reel-to-reel video tape. This tape could be played on any video tape machine.

These secondary recordings were considered the best sources available because they could be easily copied and accessed. Strip charts and computer tapes are reasonably faithful reproductions of the "original" data. If some spacecraft sensor reads 42 and this is preserved on the Memorex tape as a PCM-encoded number 42, then it will read out on the 9-track tape as 42 and on the strip chart somewhere accurately between 40 and 50 on the pre-printed grid. There's no loss of precision. The spacecraft told you 42 and you have 42 in your data stream. This was a well-developed, well-tested method because it was used on previous missions and would be used for subsequent missions. It was the general case.

But the process of reading out the video signal was entirely different. There was no magic way of electronically converting the embedded slow-scan signal to a standard video signal. You had a slow-scan monitor that could display the video, and then they just pointed a standard video camera at the screen. This is a fairly ingenious and reliable method, but it obviously accepts some degradation in the picture. It was deemed acceptable because of the one-off nature of Apollo 11's television solution. Previous missions had the benefit of the CSM's high-gain antenna and wider bandwidth. Subsequent lunar surface missions would rely on the erectable S-band antenna. (Apollo 11 carried one, but would have set it up only in an emergency.)

The usable form was considered the primary video record, even though it was technical a secondary format. If you wanted to re-read the video portion of the telemetry signal, you would have needed to reassemble all that one-off equipment: the slow-scan decoder and monitor and a camera. At no time did NASA contemplate a less lossy method of obtaining the picture from Apollo 11 television. And this was not considered irresponsible back then. Kinescopes and telecines were standard methods of converting between picture formats—film and videotape. These were all lossy methods and considered acceptable and common at the time. NASA considered the primary visual records of the mission to be the film photography, not the live television.

NASA did retain the original tapes for as long as possible. The decision to reuse them for a later mission, however, was not irresponsible. It was the proper decision in the lurch they had been put in by the supplier of new (faulty) tapes. Viewing this decision in light of late and improbable data recovery techniques is unfair. The situation is unfortunate, but utterly unrelated to any sort of credible claim of a hoax.

But to summarize all this in an answer to your question, the Memorex tapes were both original and backup. They are the earliest and best recordings of the video signal, but they were never meant to be used as a primary source. The primary source was the slow-scan-to-NTSC conversion, and the (relatively unusable) telemetry tape played the role of backup.

Thanks Jay. Most of it over my head of course but i appreciate your time. As with most hoax topics i wonder why this information isn't given out by people when they debate this kind of stuff.

59

The Hoax Theory / Re: Telematry Data

« Last post by JayUtah on November 02, 2024, 03:18:21 PM »

I think there's some confusion between what is considered original and what is considered backup. The Memorex telemetry tapes that were overwritten with new data were those from Apollo 11 and a bunch of other missions. These were the tapes running through the telemetry recorders during the Apollo missions and, as such, constitute the first recording of the data. That is the sense in which they could be considered originals. For Apollo 11, this also constituted the embedded television signal. Intuitively we would think of these as "originals" and therefore worthy of special protection. But the facts are slightly more complicated.

None of the data were directly usable from the tapes. To access the data on them, you needed telemetry tape machines, which were comparatively expensive and uncommon and most in demand for recording new data. You needed a technician to configure the heads and channel processors. This was especially true for the embedded video signal, which was a complete one-off used only on Apollo 11. You needed custom decoding hardware and technicians to operate it.

Therefore the first thing that was done with the telemetry was to read out the different data channels onto standard 9-track, 6250 bytes-per-inch computer tape or on paper strip charts. The charts can be read directly and photographically copied, and the standard computer tape could be run through any of the computers at NASA. For Apollo 11, the video signal was decoded and converted to a standard NTSC signal and recorded on standard reel-to-reel video tape. This tape could be played on any video tape machine.

These secondary recordings were considered the best sources available because they could be easily copied and accessed. Strip charts and computer tapes are reasonably faithful reproductions of the "original" data. If some spacecraft sensor reads 42 and this is preserved on the Memorex tape as a PCM-encoded number 42, then it will read out on the 9-track tape as 42 and on the strip chart somewhere accurately between 40 and 50 on the pre-printed grid. There's no loss of precision. The spacecraft told you 42 and you have 42 in your data stream. This was a well-developed, well-tested method because it was used on previous missions and would be used for subsequent missions. It was the general case.

But the process of reading out the video signal was entirely different. There was no magic way of electronically converting the embedded slow-scan signal to a standard video signal. You had a slow-scan monitor that could display the video, and then they just pointed a standard video camera at the screen. This is a fairly ingenious and reliable method, but it obviously accepts some degradation in the picture. It was deemed acceptable because of the one-off nature of Apollo 11's television solution. Previous missions had the benefit of the CSM's high-gain antenna and wider bandwidth. Subsequent lunar surface missions would rely on the erectable S-band antenna. (Apollo 11 carried one, but would have set it up only in an emergency.)

The usable form was considered the primary video record, even though it was technical a secondary format. If you wanted to re-read the video portion of the telemetry signal, you would have needed to reassemble all that one-off equipment: the slow-scan decoder and monitor and a camera. At no time did NASA contemplate a less lossy method of obtaining the picture from Apollo 11 television. And this was not considered irresponsible back then. Kinescopes and telecines were standard methods of converting between picture formats—film and videotape. These were all lossy methods and considered acceptable and common at the time. NASA considered the primary visual records of the mission to be the film photography, not the live television.

NASA did retain the original tapes for as long as possible. The decision to reuse them for a later mission, however, was not irresponsible. It was the proper decision in the lurch they had been put in by the supplier of new (faulty) tapes. Viewing this decision in light of late and improbable data recovery techniques is unfair. The situation is unfortunate, but utterly unrelated to any sort of credible claim of a hoax.

But to summarize all this in an answer to your question, the Memorex tapes were both original and backup. They are the earliest and best recordings of the video signal, but they were never meant to be used as a primary source. The primary source was the slow-scan-to-NTSC conversion, and the (relatively unusable) telemetry tape played the role of backup.

60

The Reality of Apollo / Re: Interesting video about the lunar rover, politics and Elon Musk

« Last post by bknight on November 02, 2024, 08:41:47 AM »

The only aspect concerning Elon that I find appropriate is he is a capitalist.
Mission to Mars, not scientific but how much he is able to make out of the idea.
Mission to the Moon, see above.
Tesla is a "a transportation that reduces greenhouse gases produced by transportation", no build a transportation system that is funded in part by the federal government reducing cost to the consumer.
Don't get me wrong I support his space plans but don't agree with some of his testing methods.  I'm neutral when it comes to EVs. Outside a few states the vast amount of energy production is by consuming fossil fuels.  Where is the savings/reduction?