Recording of "outer space" music heard on Farside by Apollo 10 crew

originally posted by: game over man
The point in the video is the astronauts would have recognized it as radio interference and they did not. Are their transcripts online?

They're pilots. They wouldn't have taken an electronics guy. All they'd know is that it sounded weird. But as far as being able to even explore what they were hearing, and how to try to isolate it without ground support to tell them what to do, not very likely.

originally posted by: Bedlam

originally posted by: game over man
The point in the video is the astronauts would have recognized it as radio interference and they did not. Are their transcripts online?

They're pilots. They wouldn't have taken an electronics guy. All they'd know is that it sounded weird. But as far as being able to even explore what they were hearing, and how to try to isolate it without ground support to tell them what to do, not very likely.

You think they have never heard radio interference before? You're telling me the astronauts are that illogical and for an hour they thought they were listening to aliens? Why would they presume aliens?

originally posted by: game over man

You think they have never heard radio interference before? You're telling me the astronauts are that illogical and for an hour they thought they were listening to aliens? Why would they presume aliens?

Um, because they're in space? They didn't "presume aliens", that's the spin to sell page clicks.

eta: if you'd have heard it on the ground, they'd have likely made comments about something else. But being on the back side of the moon, it's an obvious comment to call it 'alien music'.

I wish I had something constructive to ass, but this is all I have.
Am I the only one that's made really uncomfortable by these audio recordings? I've watched all the videos posted in this thread so far, and they all make me feel really uncomfortable. They make the hair stand up on the back of my neck and and give me this weird angsty feeling. I'm not saying it means anything, but the sounds make me super uneasy. Anyone else?

Any musicians out there? Right away I knew that high-low woosh woosh. It sounds like a flanger.

en.wikipedia.org...

From the wiki:

Flanging /ˈflændʒɪŋ/ is an audio effect produced by mixing two identical signals together, one signal delayed by a small and gradually changing period, usually smaller than 20 milliseconds. This produces a swept comb filter effect: peaks and notches are produced in the resulting frequency spectrum, related to each other in a linear harmonic series. Varying the time delay causes these to sweep up and down the frequency spectrum. A flanger is an effects unit that creates this effect. In some cases the two signals will become so close that it almost fades away to oblivion called "sucking air." It has also been called the "Darth Vader effect."

Part of the output signal is usually fed back to the input (a "re-circulating delay line"), producing a resonance effect which further enhances the intensity of the peaks and troughs. The phase of the fed-back signal is sometimes inverted, producing another variation on the flanging sound.

So it's pretty simple I think...I would guess that they were just picking up their own signal(s)/emissions bounced off the moon itself. The delay that caused the flanging effect was from the travel time...straight line had the shortest time, while the signal bouncing back from off-centre would come back just a little later than that.

The moon would also be blocking all the signals from Earth, so a weak signal would come in much 'louder' than normal. It's not that the signal is any louder/hotter itself, it's that the background is much quieter. I wonder if they tried to pick up any of the big stations on their way to the moon? And how well they came in for how far? There were some really big radio stations back then.

Also fun, a flanger is iirc used quite a bit on on Pink Floyd's "Dark Side of the Moon," particularly in "On the Run."

Another wiki link: list of recordings with a flanging effect.

I think it's also worth clarifying some of the clams about secrecy.

The mission transcripts were classified, but if you look at this document:

www.jsc.nasa.gov...

You can see on the front cover when that classification was changed to 'U', or unclassified.

The video claims that they were hidden until 2008, but as this article makes clear the audio and documents were available to anyone who was prepared to put in some effort:

www.airspacemag.com...

a reply to: smurfy

There is sound in space, you just can't hear it without a pickup.

Fair enough. I was aware that sound does indeed exist in space in the form of electromagnetic vibrations.

However, there is NO SOUND in space that can be HEARD by the astronauts (within the context the OP story is suggesting,) based on my limited understanding of the cosmos, is was what I was trying to convey. Space is a vacuum.

Again:

Sound needs something to travel through to get from one place to another. On the Moon, since there is no air, sound cannot travel above the surface. So, there are no sounds on the surface of the Moon. When the Apollo astronauts were out on the Moon’s surface, they could only talk to each other, and to mission control, by using the radios in their air filled helmets. Even when the astronaut in the photo to the right, hit a metal tube into the ground with a hammer, no sound was made.

From what I understand, there exist sophisticated instruments which can detect the different electromagnetic vibrations. It then converts these electromagnetic frequencies, which cannot be heard by human ears, into audible sound-waves that can be heard by human ears at a later date.

The point is: I still don't get how the astronauts could claim the sounds they were hearing were coming from "out there".

Since we are on the topic, here is something I have meditated to off and on over the past few years.

originally posted by: Involutionist

The point is: I still don't get how the astronauts could claim the sounds they were hearing were coming from "out there".

They didn't.

originally posted by: 11andrew34
Any musicians out there? Right away I knew that high-low woosh woosh. It sounds like a flanger.

en.wikipedia.org...

From the wiki:

Flanging /ˈflændʒɪŋ/ is an audio effect produced by mixing two identical signals together, one signal delayed by a small and gradually changing period, usually smaller than 20 milliseconds. This produces a swept comb filter effect: peaks and notches are produced in the resulting frequency spectrum, related to each other in a linear harmonic series. Varying the time delay causes these to sweep up and down the frequency spectrum. A flanger is an effects unit that creates this effect. In some cases the two signals will become so close that it almost fades away to oblivion called "sucking air." It has also been called the "Darth Vader effect."

Part of the output signal is usually fed back to the input (a "re-circulating delay line"), producing a resonance effect which further enhances the intensity of the peaks and troughs. The phase of the fed-back signal is sometimes inverted, producing another variation on the flanging sound.

So it's pretty simple I think...I would guess that they were just picking up their own signal(s)/emissions bounced off the moon itself. The delay that caused the flanging effect was from the travel time...straight line had the shortest time, while the signal bouncing back from off-centre would come back just a little later than that.

The moon would also be blocking all the signals from Earth, so a weak signal would come in much 'louder' than normal. It's not that the signal is any louder/hotter itself, it's that the background is much quieter. I wonder if they tried to pick up any of the big stations on their way to the moon? And how well they came in for how far? There were some really big radio stations back then.

Also fun, a flanger is iirc used quite a bit on on Pink Floyd's "Dark Side of the Moon," particularly in "On the Run."

Another wiki link: list of recordings with a flanging effect.

My favorite stomp is my stereo flanger.

I also recorded a tune using the sounds of saturn as a background.

In space, no one can hear you scream.

Come on people. You would have to touch helmets to hear each other without radio.

what? no one's ever seen a space movie?

originally posted by: Elementalist
Anything classified should be illegal.

Especially when tax payers paid for most of the trips.

So a government employee, say like a librarian, shouldn't have any personal privacy?

They are after all paid by tax payers...

a reply to: Involutionist

Thanks for that creepy video.

a reply to: Skush

Are you sure that that sound you hear in the clip is the actual "music" the astronauts heard? It doesn't actually say it is.

they confirm in the video that the sound sounds like "outer space music" - does not mean its music, sound more like heavy wind blowing down a mic. but thats what they described it as.

They described it as 'outer spacey', 'outer space type' and 'whistling'.

The kind of thing that was common in science fiction films of the day:



Radio interference type noises.

RF demodulators in the receivers back then had component noise and oscillator injection drift. They were listening to their equipment component noise as the temperatures drifted up and down because of moving and out of sunlit regions. AGC (automatic Gain Control) and AFC (automatic frequency control) circuitry was working to compensate for the temperature induced drift. I remember working on circuitry back in the early 70's on military equipment.

originally posted by: 11andrew34
Any musicians out there? Right away I knew that high-low woosh woosh. It sounds like a flanger.

Good post. Now add in the fact omitted by HuffPost that the sound came over the VHF link between two spacecraft maneuvering a few tens of miles apart, and you have a recipe for such feedback interference.

Is the 'g' hard or soft in pronouncing 'flanger'?

originally posted by: Involutionist
Fair enough. I was aware that sound does indeed exist in space in the form of electromagnetic vibrations.

Sound isn't an 'electromagnetic vibration', so it doesn't exist in that form.

However, there is NO SOUND in space.

Poifect.

From what I understand, there exist sophisticated instruments which can detect the different electromagnetic vibrations. It then converts these electromagnetic frequencies, which cannot be heard by human ears, into audible sound-waves that can be heard by human ears at a later date.

Sound is not low-frequency radio. The difference between radio waves and sound is qualitative. They aren't related in any way. So it's not just a matter of changing the frequency to that of sound. You can have radio-frequency sound, which won't radiate off an antenna, and EM waves in the frequency of human hearing, and you can't hear it. Sound is not radio, radio is not sound.

Your ears hear pressure waves in a compressible medium. Water and air are the two usual ones. Radio is not a pressure wave. You can't hear it, even if it's in an 'audible frequency', because it's not sound at all.

originally posted by: JimOberg

originally posted by: 11andrew34
Any musicians out there? Right away I knew that high-low woosh woosh. It sounds like a flanger.

Good post. Now add in the fact omitted by HuffPost that the sound came over the VHF link between two spacecraft maneuvering a few tens of miles apart, and you have a recipe for such feedback interference.

Is the 'g' hard or soft in pronouncing 'flanger'?

Soft. The first way people did it was by mixing in a duplicate recording from a reel-to-reel recorder and riding a finger on the reel flange.

originally posted by: game over man
The point in the video is the astronauts would have recognized it as radio interference and they did not. Are their transcripts online?

originally posted by: Bedlam
They're pilots. They wouldn't have taken an electronics guy. All they'd know is that it sounded weird. But as far as being able to even explore what they were hearing, and how to try to isolate it without ground support to tell them what to do, not very likely.

Plus, the fact that they were somewhat isolated from other EM interference could mean that the sound itself was isolated.

So even if a pilot has heard feedback interference before (on Earth), it was probably as only a small part of a larger background noise, and it maybe didn't stand out among that background interference. But without the other background interference the feedback interference stands out and is more obvious.

a reply to: Phage

phage, you really behaved like mr. spock right there! this was a joke? you know, "pink floyd", "dark side of the monn"? "space oddity"? "rocket man"?

but thanks for the lesson!