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41

Tom Jones talks about it some in his memoir "Skywalking" when he describes an EVA carried out on shuttle mission STS-98: Inside the airlock when it is pressurized Through the helmet shell, from the world outside the space suit, came a muted, sporadic tinkling sound, the result of minor collisions between our drifting tools and the airlock walls. ...


36

Your premise is incorrect. Microphones have been carried on Mars missions, they just failed to work. Mars 2020 (now Insight) will carry microphones. NASA spacecraft that traveled to Mars in the past have carried microphones twice. Unfortunately, one of those missions, the Mars Polar Lander, failed. The Phoenix Lander had a microphone on the spacecraft’s ...


33

Curiosity does not have speakers. As the OP's linked article states: This was accomplished using Curiosity's Sample Analysis at Mars (SAM) instrument. It "sang" the song by vibrating at different frequencies. More information on how this was accomplished is available in this LA Times article: The Sample Analysis at Mars instrument, or SAM, isn't ...


18

An article in the Washington post explains: the rover’s sample analysis unit vibrates at different frequencies to move soil samples. Normally, those vibrations sound remarkably like the noises robots make in Disney’s Wall-E, but when you string them all together, something similar to “Happy Birthday” results.


18

tl;dr: There's certainly some propagation of sound waves possible at 100 km altitude. With a density a million times lower than at the surface the mean free path of individual molecules will approach a millimeter, so ultrasonics might be impacted, but for Human or GoPro frequencies it will be much quieter, but still there. Till what altitude above earth ...


17

The shuttle Orbiter's wing leading edges, constructed of reinforced carbon-carbon (RCC) composite material, were tested in part by technicians tapping on them and listening to the resulting sounds. It didn't work all that well though, and was replaced by infrared thermography. Sources STS-121: The Hardest Launch, Part 3 1986 Press Manual


15

The title of the question asks Till what altitude above earth sounds can be heard? @uhoh gave a detailed answer to that question. I'll instead speculatively answer an implied question in the body of the OP, What is the sound in the linked video? The OP implicitly assumes the sounds in the video were transmitted through the air to a microphone. (Many ...


14

According to WIRED Magazine's article and video Watch Astronauts Answer Your Burning Questions about Space (also viewable on YouTube): Sounds exist in space, but humans can not hear them. As pointed out in the question, there is not going to be any significant, perceptible sound transmitted through space at the altitude of the ISS (now roughly 400 km). The ...


13

Many years ago, as a young engineer, I worked for Hamilton Standard who developed the Space Suit, and which had the remit to develop a Power Tool for Astronauts for the purposes of repairing the Space Telescope while in orbit. We interviewed astronauts regarding their experiences working 'extravehicular' ...meaning in space, mainly at that point, in the ...


12

This is a fantastic question! There are some sounds recorded by a GoPro camera high in Earth's atmosphere in the video linked in the question How did the tangential thrusters for the 2014 LDSD test spin-up then spin-down so nicely? also shown below. The sound starts at 120,000 feet (36.4 km) and then is heard at about 180,000 feet (54.5 km). Using NASA's U....


12

I'm not sure how widely you are casting the breadth of your question. But I know jet engine mechanics always listen to a turbine as it runs up, reaches steady state, then is powered down. I knew the chief engineer for Flying Tigers in the 1970s who was a grizzled old guy who put his ear against an engine's nacelle to listen to the bearings and oil pumps. He ...


11

Submitted as a somewhat subjective answer - you never know what sound editors did. These are two clips from the early shuttle IMAX file The Dream is Alive. This agrees fairly well with my experience of hearing the more white-noisy main engines followed by the louder crackly, snappy rumbling of the solids. There are significant differences between the sound ...


10

Yes, you can hear the noise of anything that hits the outside of the ISS, because from that point there is no vacuum - vibration is passed to the inside of the ISS where it is audible. This is all reasonably self-evident. This includes micrometeoroid impacts, as Hobbes mentioned, but also noises from crew members moving on EVA, their tools and anything else....


9

They wouldn't work. In a pipe, wind blowing over the fipple, or past a reed causes vortices which give lots of different frequencies. Then at the open end of the pipe (or open finger holes) the change to a fixed pressure causes most of the vibration to be reflected back down the pipe, setting up standing waves at various harmonics, which produce the tone. ...


9

There's a lot of variations in the astronauts' subjective impressions of the sound: "muffled roar", "gutteral roar", and allusions to infrasonic vibration, for which "rumble" might be a fair description. Collins, in Carrying The Fire: Trust your instruments, not your body, the modern pilot is always told, but this beast is best ...


9

If you count ultrasound inside metal as sound: From this answer to Why do they believe that the Bigelow Expandable Activity Module has “taken a hit”?: After some research and this article I found out that they are using a system called Distributed Impact Detection System (short DIDS) to detect these impacts. NASA describes the system like: DIDS units are ...


8

The amount of white vapor present at the beginning and end of the test suggests that there is indeed a water spray down within the flame trench. There is no need for above-grade spray because the rocket is tied down and cannot lift off. The structure of the test stand itself will provide substantial acoustic shielding for the rest of the vehicle.


8

If you count ultrasound Several leaks aboard the ISS were first discovered by an increase in the rate of depressurization of the station that could not be accounted for by known causes. These can be localized to "which compartment?" by closing various hatches and monitoring the pressure drops in them. However before you can FIX the darned leak, you ...


8

If you count seismic vibrations as sound From this answer to How are the most sensitive seismometers on Mars protected from the most powerful jackhammer on Mars just a few feet away?: The SEIS team had this to say in Review of the commissioning phase of the SEIS seismometer on Mars. During the same period as the calibration operations, the SEIS seismometer ...


7

How many grains of sand does it take to form a heap? An orbiting spacecraft is flying many times faster than the speed of sound. It's starting in atmosphere too thin to sustain an audible shock wave. As it descends, it's going to be producing a shock cone continuously, but in the very thin atmosphere high up, the amplitude of the shock wave is too faint to ...


7

I think you might have some misconceptions about what that spectrogram represents, and how it might have been processed. The purpose of recording audio "room tone" is not to remove background noise, but to add it back in during post processing, to make sound edits less jarring. It would be useless for removal of true, uncorrelated noise. The spectrogram ...


7

A real stethoscope has some features that make it useful in normal use, but would be a hindrance in your scenario. The sound conductance medium is the air column in the tube, not the tube itself. Between ships or spacesuits, the air column would not be present. The flexible material of the tube is a poor sound conductor. The ear pieces help to direct the ...


7

Expected noise levels can be found in the environmental assessment. For Falcon 9: 156.1 ± 4.9 dB (unweighted) at 125 ft. For Falcon Heavy: 160.9 ± 4.9 dB (unweighted) at 125 ft. So asdfex's comment is in line with what SpaceX expects/has calculated. Now this is a 2011 study, after the first v1.0 launch but predating the various upgrades to the F9. I ...


7

The amount of energy involved in a take off and landing will be roughly equal to the mass being moved, and approximately the same proportion of energy will be turned into sound given the same engines are involved. Going up a falcon heavy is around 1400 tonnes, coming down the stages have split apart and are almost empty. Have not found authoritative numbers ...


6

Of course there is no sound in the vacuum of space, as there isn't a sufficient medium to propagate sound waves. Your teacher was referring to a medieval concept known as the music of the spheres. Musica universalis (lit. universal music, or music of the spheres) or Harmony of the Spheres is an ancient philosophical concept that regards proportions in the ...


6

Short answer: These "sounds" consist of vibrations produced by the astronaut's movements and his suit systems and transferred through his space suit, camera enclosure and PCB the microphone is soldered to plus electrical and digital noise added by the sound processing pipeline. Long answer: Microphone is an electromechanical device, that converts ...


6

It is a sound suppression system like the one developed by NASA for the Space Shuttle in the 1980s. It was required to keep the sound level below the required 145 dB. See: https://www.nasa.gov/mission_pages/shuttle/launch/sound-suppression-system.html On launch pad 39A in Cape Canaveral, a water tower dumps 300,000 gallons of water in less than a minute ...


6

(not an answer yet, I have yet to find SPL data for the SRBs) Thanks to the discussion and videos it does seem that the SRBs are louder. However, I had a vague notion that turbulence was important, and Reynolds number scales with jet velocity. The paper "Arenas, Jorge P., and Ravi N. Margasahayam. "Noise and vibration of spacecraft structures."...


5

However, once in space, the vacuum does not transmit sound, so any sound produced by the engines will be contained to the spacecraft. No. The sound produced by the engines is mostly in shockwaves in the exhaust plume, and those leave the spacecraft just fine in a vacuum. There might be a slight increase because vibrations transmitted through the thrust ...


5

Yes and no. It's a yes in that gravity is often responsible for the density of the atmosphere, at least on a planet or gas cloud. Higher air density often means a higher speed of sound for the same composition of atmosphere, although there are other factors involved. It's a no in that gravity does not change the path of sound. Say you had 2 identical ...


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