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I'll confess immediately that I didn't read TFA. I just want to drop this link to a nice Isaac Asimov essay, back from 1962:
Not as We Know it – The Chemistry of Life

Remember that Asimov was a professor of biochemistry. In the article, he investigates alternatives to the chemistry of life as we know it. He comes up with the following list:

[H]ere, then, is my list of life chemistries, spanning the temperature range from near red heat down to near absolute zero:
1. fluorosilicone in fluorosilicone
2. fluorocarbon in sulfur
3.*nucleic acid/protein (O) in water
4. nucleic acid/protein (N) in ammonia
5. lipid in methane
6. lipid in hydrogen
Of this half dozen, the third only is life-as-we-know-it. Lest you miss it, I've marked it with an asterisk.

When you read the article, you may want to skip the first bit and start from about the paragraph "Well, that's what I want to discuss."

My brother Karl Jansky and His Discovery (1929) of Radio Waves from Beyond the Earth

Do you think that ET will be using encryption?

Even if not, they'd still likely be using data compression, making it look like noise. I don't expect we'd be able to recognize a standard communication signal.

If we find a signal, it'll either be a deliberate hail like the Arecibo message, or a bit of technological noise, like the DEW and astronomical radar signals we transmit.

In three decades, we have sent only sixteen deliberate hails. If other civilizations are as quiet as us, the odds of hearing a hail are low - I can imagine a galaxy teeming with technological civilizations, each waiting for somebody else to open a conversation.

Recognizing technological noise is hard, as our bias is going to be to assume a natural origin. It's possible that we've got some bit of astrophysics wrong because some phenomenon we assumed was natural and worked into our theories was actual static from ET's Criswell structures. At best we might see something like the Wow! Signal: we see something but we don't know what it is.

(Please enjoy My Brother Karl Jansky and His Discovery of Radio Waves from Beyond the Earth).

Wow! this is so not off-topic. wake up mods. try google.

here, I'll make it easy for you.

http://www.bigear.org/6equj5.htm

In the spirit of the "Wow!" signal, I hereby declare this to be the "wtf?" signal.

The canonical announcement for this kind of event is "Wow!".

So what's the story behind the classic WOW!-signal?

No, I think you mean:

1) Bad result, but your graduate advisor yells at you. This is not a successful experiment.

2) Good result, but your graduate advisor takes the credit for it. Your advisor might consider this a successful experiment, but then he also calls you his "lab bitch" at faculty luncheons. Call it a draw.

3) Good result, but you will be unable to reproduce it ever again. Like the fabled WOW! event in radio astronomy, this tantalizing glimpse of success will haunt you through your waking hours, spent alternately drinking and working as an assistant manager at Radio Shack.

4) Bad result, but your graduate advisor is "accidentally" vaporized in the process. Although not strictly a successful experiment, you hear no complaints from your fellow grad students, the surviving faculty members, or the long-suffering department secretary as you are lead to the police car, leaving your former lab (and former career in academia) in glorious, if somewhat radioactive, flames.

Hope this helps!

That's actually a good idea. Take a look at:
Argus NGRT
Square kilometer array

Also, I think there was a /. story about LOFAR a few days ago which is basically the sq km array V 0.5

IANARA but what I understand is that computer tech is now getting to the point where you can basically make a reverse phased array. In a phased array you can generate a fully steerable radar beam with no moving parts by having a grid of radio emitters. Each emitter puts a specific delay on the waveform it generates so that the constructive interference of all the elements makes a big beam that you can scan all over the sky. Also, you can generate multiple beams this way. This is great if, for example, you detect an incoming airplane with the main beam, you simply divert a small portion of the beam to track that airplane while the rest of the big beam continues sweeping the sky.

Well, if you have a large array of simple detectors - they don't have to actually be dishes, simple aerials will do, you can take and run a computer network to look at all the incoming raw radio data and back extract the intensity and direction of each incoming signal. With this system, you can watch an artibrary number of signals at once, only limited by computing power. Furthermore, your 'telescope' watches the entire sky at once. Here's a rundown of this array vs traditional radio astronomy:

Array tech:
Can view multiple object at once
Can track rapidly moving sources
Easily discriminates space from Earthbound or LEO sources
Detects short, transient sources
Requires massive amounts of computing power

Traditional (big dish) tech:
Can only view multiple objects if they are very close to one another
Can only track moving sources as quickly as the dish can be accurately turned
Has trouble discriminating between space and earthbound sources unless you take the time to move the dish (to see if the signal goes away - an earthbound source that's bleeding into a dish will still be present even if the dish is turned slightly)
Only sees transient events if it happens to be looking at them when they happen.
Requires little computational power

The primary limitation is computer power. The square km array is basically a radio telescope that will cover the better part of Australia with a total reciever area of a square km, easily outpowering all of the radio telescopes ever built. However, this telescope, at full resolving power can only look at a few objects at a time at a single frequency, not the entire sky since doing so for so many elements would require something like a metric fuckload of teraflops. Instead, some elements will be dedicated to a low resolution/sensitivity whole sky scan to detect transient events and the rest of the array will train its virtual beams on various objects of interest or on said transients within a fraction of a second of their detection with the wide scan.

Here's where I think amateurs could come in:
the square km array, if it's ever built, will only look at the Southern hemisphere. Furthermore, it will be taken up by radio astronomers, not SETI or amateurs. I know Paul Allen is setting up some sort of massive SETI system not unlike this but, IT would be nice to have more than one group doing this.

So here's what should be done:
Set up a system of radio recievers that people can easily build/buy to put on their computers.
Have these computers slaved to some sort of very accurate time clock, eg: GPS
Have each computer pull out all of the waveforms from a pre-agreed frequency, eg: standard SETI search frequencies)
Set up a central or distributed system to pull out any non-Earthbound sources. (this array tech is great for IDing non-human sources since widely spaced recievers can easily triangulate distances to nearby sources out to a few hundred km, eliminating the vast majority of non-ET tr

I have a vested, sentimental interest in these places so I'm going to plug them:

The Big Ear telescope, operated by Ohio State University, was built on the grounds of Perkins Observatory, between Columbus and the town of Delaware. Delaware is the location of my alma mater, Ohio Wesleyan University, which owns and operates Perkins as a public outreach center. (OSU used to have some financial involvement, but pulled out a few years ago.) In other words, Perkins is no longer a research observatory: it is entirely dedicated to educating the public about astronomy and allowing people to look through their telescopes. (In other words, it's awesome.)

For a couple years after Big Ear had stopped being used it just stood there on the property. I remember taking a walk around the grounds in 1998 with a friend, peaking in the windows of the little building with the control room, filled with junk. It was sort of sad to see it so neglected. Even worse, the land on which it sat had been sold by my school to the neighboring golf course. We actually ran into a golfer while we were there, and he took the time to tell us how much he wished they would tear the telescope down so they could extend the driving range. And not too long afterwards, it happened. Big Ear is gone.

There's some really great stories to tell about Hiram Perkins, too, but I don't want to ramble on too long... The short version: Perkins Obs. was the second observatory he built, and at the time it was completed, it housed the third largest telescope in the world. That telescope, now with an even bigger mirror, lives at Lowell Observatory in Flagstaff, but was still owned by Ohio Wesleyan until around the time I graduated (1998) when OWU sold it completely to Lowell. It's now operated jointly by Lowell and Boston University, which happens to be where I went after OWU. I took two trips out there to use it before I got my masters in astronomy and left BU to come back to Ohio.

Here's a few links to entertain you:

• Perkins Observatory. Make sure the read the history section.
• Big Ear
• Lowell Observatory
• Lowell's page about the Perkins telescope
• Ohio Wesleyan Astronomy Club, with info about the first Perkins Observatory. Some of the pages here are unchanged since I wrote them around 1997. Looks like they took down the page about how run down the building is and saying that we need money from the university to keep it from falling apart.

If you live anywhere near Columbus, I highly recommend visiting Perkins sometime. They have great facilities and a fantastic staff. It's a great way to spend an evening.

I'm surprised nobody has mentioned the WOW signal. read the link..it'll send chills down yer spine!

Just in case anybody is still reading this story, I just found an article by her, which is very amusing. And she says it was OK that he got it. I must admit that I tend to think that she's wrong on that one, I think she should have had it.... :-)