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Mysterious Sounds Recorded During Near Space Balloon Flight
An anonymous reader writes: LiveScience reports on strange sounds recorded by microphones on board a high altitude balloon. The sounds were captured at altitudes of up to 36 kilometers, higher than any such experiment to date. Most of the noises are in Infrasound frequencies — below 20 Hz. Researchers aren't sure what caused the noises, but they have a few theories: "a wind farm under the balloon's flight path, crashing ocean waves, wind turbulence, gravity waves, clear air turbulence, and vibrations caused by the balloon cable."
Of a pod of air whales.
"The average reporter we talk to is 27 years old......They literally know nothing." - Ben Rhodes
This is what it sounds like when doves cry
It's the theme from Close Encounters of the Third Kind!
its not politically correct. They prefer to be called undocumented martians
have you seen my sig? there are many others like it but none that are the same
On 31 May 2003, a group of UK researchers held a mass experiment where they exposed some 700 people to music laced with soft 17 Hz sine waves played at a level described as "near the edge of hearing", produced by an extra-long-stroke subwoofer mounted two-thirds of the way from the end of a seven-meter-long plastic sewer pipe. The experimental concert (entitled Infrasonic) took place in the Purcell Room over the course of two performances, each consisting of four musical pieces. Two of the pieces in each concert had 17 Hz tones played underneath. In the second concert, the pieces that were to carry a 17 Hz undertone were swapped so that test results would not focus on any specific musical piece. The participants were not told which pieces included the low-level 17 Hz near-infrasonic tone. The presence of the tone resulted in a significant number (22%) of respondents reporting anxiety, uneasiness, extreme sorrow, nervous feelings of revulsion or fear, chills down the spine, and feelings of pressure on the chest.[34][35] In presenting the evidence to the British Association for the Advancement of Science, Professor Richard Wiseman said, "These results suggest that low frequency sound can cause people to have unusual experiences even though they cannot consciously detect infrasound. Some scientists have suggested that this level of sound may be present at some allegedly haunted sites and so cause people to have odd sensations that they attribute to a ghost—our findings support these ideas."[33]
https://en.wikipedia.org/wiki/...
It teh guvernmint....
"If any question why we died, Tell them because our fathers lied."
...huh, so THAT'S what microphones sound like when they freeze over at low pressures.
To do something right, you often have to roll up your sleeves and get busy.
Well, aliens and high altitude balloons are known to have an affinity for one another, and one is often mistaken for the other.
That's so racist! Not all undocumented extraterrestrial immigrants are Martians, neither are all Martian immigrants undocumented.
Required reading for internet skeptics
Couldn't sit through them, couldn't skip them. Is this what science has come to? "Newton's laws ... brought to you by Fig Newtons!" Why is all the money in the hands of the private sector, so they have to annoy you by forcing you to watch a full 30-second ad? If their product was really good wouldn't word-of-mouth suffice?
...around 5 Torr, which is actually quite a lot of Torr.
(Not using modern units because _they_ used Miles.)
So let's not have any of that "It's Vacuum up there!" nonsense.
What I propose is that these are local pressure variations due to Micro-Meteorites passing nearby, merrily vaporizing away, even though the resulting light is too dim to see from ground.
BTW, for giggles, look up "hissing meteorites", as in Electrophonics.
"Vibrations caused by the balloon cable" is listed last? I'd list it first!
Obviously it's all those souls trapped in the vault of heaven.
"It's .. Dethklok. It's Dethklok!"
Dethklock
It's the brown note.
The most plausible theory is that microphones are made and sold on Earth to work at soil level, or at least where humans can still hear from their ears, where air is dense enough to propagate sounds. "Near space" would be better for light, certainly not better for sounds.
Slashdot, fix the reply notifications... You won't get away with it...
This is ambiguous. Most people hearing "gravity waves" think general relativity "gravitational waves". The two are not related: http://en.wikipedia.org/wiki/Gravity_wave
That's so racist! Not all undocumented extraterrestrial immigrants are Martians, neither are all Martian immigrants undocumented.
Do they have Green Cards?
Or someone is running low on funding.
Mother Earth putting ancient brown noise emitters to use...
Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
Undocumented Terrestrials
I am Bennett Haselton! I am Bennett Haselton!
The winds at the float altitude of 120k' (36km) have frequent and sustained gusts exceeding 25 m/s. The air is thin, and barely perceptible, but the effects of vortex shedding around structures is still vexing for those of us who try to keep payloads pointed and vibrations minimized. The PSD of the vibrations is sometimes significant in the lower frequencies. The PSD of the vibration profile shifts, sometimes dramatically, in real time to the measured winds and directional changes of the payload gondola at those altitudes.
As for a microphone freezing over, the environment at those altitudes will very quickly shed any moisture accumulated in any phase on exterior surfaces. A balloon typically rotates throughout its mission, and the extreme cycling between view factors for albedo, direct solar radiation, and deep space cycle any moisture accumulated in the tropopause or below in minutes unless the surfaces are somehow unusually shielded.
It's that critter that William Shattner saw on the plane's wing....
mark