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The Scream Aliens Hear From the Earth
onehitwonder writes "Astronomers have discovered that the Earth emits awful, ear-piercing chirps and whistles that could be heard by any aliens who might be listening, according to an article up at Space.com. The sounds are created by charged particles from the solar wind colliding with Earth's magnetic field. This article explains more about the sounds and links to an audio recording of it."
If anyone ever makes first contact with us, it will to complain about the noise. Not a good start.
The usefulness of this discovery in finding planets or identifying if they have an atmosphere is interesting.
...any emission in any spectrum can be mapped to audible sound, I guess. Unless it carries information encoded in analog form meant to be replayed as sound, it will always sound like awful, ear-piercing chirps and whistles.
It as interesting as the lengths they went to create a sensationalist headline
News pattern:
1. Find interesting scientific discovery that features emissions in any spectrum.
2. Map emission to audible sound.
3. Write "The screams X emits to anybody listening"
4. Profit.
Wait, no ??? line. I must have told it wrong.
What I do for a living: Build a GPS mobile game
Can't another planet emit those noises ?
I suppose the answer is "Yes", if it has a magnetic field and if it orbits a usual star.
So, can't we use those noises to detect extrasolar planets ?
Dear Magrathea Customer Support,
it has come to our attention that the planet, namely the EARTH, which we purchased from you some millennia ago, may now be faulty. It appears to emit a high pitched screeching noise as it turns around its star. We are not sure at this point if it's perhaps an intermittent fault, however Benji can hear it every time he's out in his spaceship.
We understand that the planet is still covered by warranty, thus we would be grateful if you could send some engineers around to have a look at it. Mornings suit us best.
Kind regards
The Mice.
I'm afraid that's not true. Assuming that a sound wave could travel (particle to particle) in a gas density like that of outer space (1x10^-11 Pa), quantum effects would completely destroy any signal contained years before one particle could collide into the next.
Sound is the propagation of a wave within a medium, and in space, there is no medium with the density required to propagate a wave of any kind. Sound can travel within a medium such as a gas, however when the gas density decreases such as an atmosphere does as you get further from the surface, the sound wave attenuates, eventually petering out to nothing.
When the article says that the Earth "screams" and "whistles", it's not talking about acoustic sound waves, rather, the acoustic translation of the radio waves that are given off as a result of the helio-terrestrial effects. Whatever sensory capacity aliens have may not actually consider it to be noise, to them, it may sound pleasant, the way the waves on a beach sound to us. They may be translating it into their native sensory package, which may be "eyes" that are only sensitive to microwaves, or "ears" that only "hear" sound in a band outside of our 5hz-15khz range. Once translated, we have no idea how they'd perceive the resulting sensory experience to be. It could be a piercing shriek to them, or a gentle soothing experience.
I hate printers.
Obviously a topic ripe with potential for humor, and once again Slashdot has attempted to meet the challenge. Some would say grandly, others would say falling short. It all depends on your sense of humor, of course.
On a more serious note...
There are those who believe that our emissions of radio and TV signals are advertising our presence to book ("To Serve Man") authors everywhere, and that letting our presence be known is a Really Bad Idea. (TM) They should be happy to hear that we're being drowned out quite effectively by the Earth, itself. From what I remember, a really good detector can fish signal out of this much noise, but you also have to have more of an idea what you're looking for.
Which also has implications for SETI and such. Maybe there's more noise out there than we anticipated. We knew that suns make some serious noise, as do Jupiter-type planets. I'm not sure we knew how much noise Earth-style planets make.
Plus there's the nature of "intelligent" signals themselves. You can listen to Morse code and pretty quickly come to the conclusion that it's modulated - not random noise. Even if the concept of a BFO is foreign, you can look at it on an oscilloscope and figure that out. Next would be an AM or FM modulated signal. Even if it's Brittany Spears, as others mention, you can probably figure out that it's a modulated signal. By the time you get to Adolph Hitler opening the Olympic Games it's starting to get rougher. But I guess if you hang a spectrum analyzer on the thing, you can figure out that it's a modulates signal, find the video fields, figure out that there's a second signal (audio) on a subcarrier, etc.
Now from first principles try to intercept and decode an HTDV signal, even without DRM. Or how about spread-spectrum communications, or the various cellphone signaling mechanisms. In fact, good signal compression turns *any* signal into noise. That's because if there were anything in the compressed output that looked regular, then the compression would have been evaluated as lacking. This is even before we try to add any encryption, but in fact some compression/archive programs include password protection, because it does so good a job of de-regularizing data that it practically is encrypted.
Which brings us to "Dpilot's Corollary to Clarke's Third Law" :
"Any sufficiently advanced communications technology is indistinguishable from noise."
(Need I state Clarke's Third Law: "Any sufficiently advanced technology is indistinguishable from magic.")
Which brings us back to SETI and Drake... Maybe the signals of interstellar communication are all around us - and we're just not smart enough to recognize and decode it - yet.
The living have better things to do than to continue hating the dead.
So let's see. Middle C is about 260 Hz (with Bb slightly lower). 57 octaves lower is 2^-57 * 260 Hz, which is 5.5 x 10^14 seconds per cycle, or about 17.4 million years per cycle. Yeah, I think it's fair to say that humans aren't going to hear this signal.
...following the principles of Heisenburger's Uncertain Cat...