The Scream Aliens Hear From the Earth 223
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."
Right but that's (Score:5, Interesting)
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.
Incomplete summary (Score:3, Interesting)
The summary could have mentioned that although
somebody learned something new about the radiation produced by charged particles trapped in the Earth's magnetic field,
which seems fairly interesting. I wonder if anybody's got a model worked out yet to explain how a narrow planar beam gets generated.
needlessly anthropomophised (Score:4, Interesting)
I used to think that space,com had some credibility, but it looks like they're willing to give up any principles of sound (ooops, pun unintended) reporting in the pursuit of a good headline
All that's happened is some scientists have concluded the solar wind interacts with our magnetic field to emit radio waves. Hardly a big deal, but I suppose it's a cheap, undemanding article that attracts the uniniatated (and slashdot readers) to their advertising.
So much for a decent science article
Re:Sound without Medium?? (Score:1, Interesting)
The summary is incorrect. It is absolutely correct that sound does not travel in a vacuum. TFA is also full of wild inaccuracies.
After reading it, it became clear that this "discovery" is being used in attempt to get a bunch of grant money to build a new telescope. See, the whole world is in this mode of hysteria over spending trillions of dollars to solve imaginary problems that do not exist and that, even if they did exist, we could do absolutely nothing about. Global Warming is one example, and this "scream from Earth" is another. We must protect the hearing of our alien neighbors and not pollute their space with our noise, right?
1) Fabricate an imaginary problem ...
2) Blame Humans
3)
4) Profit!
Misleading FA (Score:5, Interesting)
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.
Re:I thought (Score:3, Interesting)
Re:I thought (Score:3, Interesting)
If your a few feet away and relatively stationary, no red shift should be occurring. The dB would drop, not the Hz. Question really is how fast the dB would drop to 0 on any given sound.
Re:What about the scream we hear from other planet (Score:3, Interesting)
Re:I thought (Score:3, Interesting)
True. However, I specifically said signal, not information for a reason.
The hypothetical situation I was thinking of was an interstellar medium density so low that the "sound" would be transmitted by a single particle travelling through space. Assuming that this particle is going to travel onwards until it hits another particle and transfers its information across, the "signal" (actually meaningful information) would be destroyed. As you cannot predict the exact state of the particle due to quantum effects, the original signal is lost.
"Information" is still transferred but it is not the same information you started with. In summary, there is no way (given solely the information at the receiving end) of reversing the quantum effects in order to retrieve the original "signal".
Humor intersects SETI and Drake (Score:5, Interesting)
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.
Re:Ear piercing in space?? (Score:3, Interesting)
I don't disagree, converting to sound is a useful process for representing what would otherwise be invisible to our senses. A lot of our understanding of science revolves around models like this. But we need to appreciate that they are only models.
Dumping your model straight back into reality and speculating what the results may be is just nonsense that suggests you've no understand of what the underlying phenomenon actually is, just the misguided idea that the model is the reality.
If I converted the peaks of mountains into a sound wave, then played it back at a pitch related to population density, I would have a fair audio representation of geographical data. It would probably also sound horrible. But would I then be correct in suggesting that Switzerland emits an ear-splitting noise that might upset Italy? I don't think so.
Re:To us... (Score:3, Interesting)
That's insightful, but I think what it says to an advanced civilization is "This Planet Has An Atmosphere, And Therefore Edible People. Now Turn Down The Damn Radio."