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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."
that could be heard by any aliens who might be listening
Assuming that "aliens" can hear at all.
Of course "hearing" is based on the detection of vibrations in the surrounding medium - a sense that is very antiquated indeed - and available to even some of the most primitive organisms. On Earth. However it's difficult to use the mere existence of such a sense to apply it to possible creatures on entirely different worlds. Perhaps given very different environments with stranger density/pressure conditions other senses would be more vital for survival. Of course one could argue that as far as we know the conditions that are suitable for life would not be that different from our own, therefore hearing would probably have to exist.
And then we can argue that the "screeches", etc, are merely the way we choose to make our computers interpret this data.
Seven puppies were harmed during the making of this post.
It's very likely the original auroral noise is much closer to your basic interstation FM hiss than "piercing chirps and whistles". Somebody put the noise through a FFT-like process which pretty much made up all the coherent beeps out of random noise.
But studying random noise seems a whole lot less interesting than trying to make out words from the chirps.
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.