I don't have the time to peruse everything ever written about Seti, but I'm sure someone has made an estimate of how many 'results', 'wu's', or Teraflops-hours the community must donate to be 95% confident that there is no detected extraterrestial signal. If so, can someone post a link to the analysis?

In other words, how many more years and resources should 'we' plan on applying to getting a good estimate of whether ET exists? Serious question.

---

May this Farce be with You

In other words, how many more years and resources should 'we' plan on applying to getting a good estimate of whether ET exists? Serious question.

I don't think that the kind of estimate you are looking for will ever be possible.

The data from Arecibo that we have crunched thus far is limited to a very narrow frequency band, 2.5 Mhz in width. Heck, an ordinary FM radio covers 20Mhz in bandwidth, or 8 times that which SETI 'listens' to. And that's only talking about radio frequencies, which are merely a small portion of the known electromagnetic spectrum. Maybe ET doesn't even use 'radio', or if they do they might well be broadcasting on a very different channel on the dial. Not only that, but our survey only covers 28% of the sky anyway, since Arecibo is located in the northern hemisphere and that is the portion of the sky visible to it.

So even if all of the current data is analyzed and re-analyzed with 100% accuracy that no signals from ET are present, we could certainly not presume that this means ET doesn't exist. For all we know, the work we are doing for SETI right now is the equivalent of trying to get ESPN on an electric toothbrush. It could be just that far off.

Now, there is a multibeam reciever that covers a larger frequency bandwidth, and the Parkes telescope in the southern hemisphere will be used to cover a greater portion of the sky... however as far as I know we are still crunching only Arecibo data. Someone please correct me if I'm wrong.

With such a limited scope of work, SETI@home could never prove that ET doesn't exist... we can only hope to get very lucky and prove that ET does exist.

Sorry this got so long. LOL.

Dig

With regard to your first question, I did find a page pertaining to current progress with signal candidates. It was just recently updated on May 9th, but to be honest I didn't derive much interesting info from it. I don't think there's been a whole lot of information coming from Berkeley in this area because unfortunately they are spending most of their valuable time on BOINC and server-related issues.

Current Progress Summary

Dig

Thx for the replies. I was beginning to think that most of the calories in this project are being spent on how to compute (e.g. see the number crunching threads) rather than why to compute.

I am not expecting that one can prove non-existence; that is an unresolvable problem. But if you begin with a set of constraints, then one should be able to estimate the resources needed to attain some statistical confidence level.

For example, how much effort is needed to process the accumulated data (moving target I guess) using just the 2.5 MHz bandwidth and 28% viewing mentioned below to a point that we are 95% "sure" there is no signal? I suppose the calculation needs to know how dense the dataset is in the 28% of the sky (derived from the telescope acceptance solid angle, etc.). Some statement about how much recorded time at each position is required to meet the confidience level. And so on.

Knowing this (or similar estimates), one (SETI management) can make decisions regarding how and when to improve or redirect the project. Not knowing this one is faced with a Holy Grail search and we aren't doing good science.

---

May this Farce be with You

For all we know, the work we are doing for SETI right now is the equivalent of trying to get ESPN on an electric toothbrush. It could be just that far off.

Dig

I love that analogy! roflmao ~:)

I agree completely with your evaluation~~and still hope we get lucky just the same...its certainly worth crunching for.

Kathy

---

Last August I asked Dan Werthimer about this. He said that considering interstellar scintillation (which can make a steady signal come and go on a time scale of seconds to hours), and considering the need to get several repeats of a real signal before thinking that it's real, a reasonable goal for SETI@home would be at least nine good scans of most the sky that's accessible to Arecibo. So far, a fair amount of this area has been scanned at least six times.

But analysis of all this data has hardly begun. It will require searching for repeated signal matches across ALL of the 2.5 MHz of spectrum, considering the doppler shifts that are likely for an alien transmitter that's in close orbit around a star (where you would expect a really big, ages-old transmitter to be located -- where it could collect lots of free solar energy forever). This will be a huge job that is not talked about much yet. We're merely listing signals (billions so far), not matching them.

As for your larger question, it's estimated that all the SETI searches to date have analyzed only one part in 10^14 (a hundred-trillionth) of the "search space" that needs to be covered. For more, see

http://SkyandTelescope.com/news/article_1322_1.asp

and

http://SkyandTelescope.com/resources/seti/article_248_4.asp

Alan MacRobert
Sky & Telescope

i just spent an entire semester at my university on analyzing nothing but the drake equation. The minimum amount needed to be spent for any meaningful estimates is about 1000 years.

We have a long long way to go.

The galaxy is just so damn big! and light travels relative to it's size, very slowly.

But what we're dealing with are "probabilities" so even though it's a 1000 years. We could detect something tomorrow. But the statistics are stacked very much against it. One thing's for sure. The longer we search, the greater our chances are for discovery. They are zero if we do nothing.

I don't have the time to peruse everything ever written about Seti, but I'm sure someone has made an estimate of how many 'results', 'wu's', or Teraflops-hours the community must donate to be 95% confident that there is no detected extraterrestial signal. If so, can someone post a link to the analysis?

In other words, how many more years and resources should 'we' plan on applying to getting a good estimate of whether ET exists? Serious question.

---

<img src="http://www.boincstats.com/stats/banner.php?cpid=b3c0c2639ea110901bd0970a1c22efcd">

With regard to your first question, I did find a page pertaining to current progress with signal candidates. It was just recently updated on May 9th, but to be honest I didn't derive much interesting info from it. I don't think there's been a whole lot of information coming from Berkeley in this area because unfortunately they are spending most of their valuable time on BOINC and server-related issues.

Current Progress Summary

Dig

I was wondering what ever happened to this page. It would be great if we could receive some insite on the project results. How does Seti Team spend it's time on the project? A list of the most promising candidates, which will include a amended list once in a while.
It's great the we are always informed of the outages and the problems with the hardware and the software but honestly we want to know that what we are sendng back to Seti, is really making a difference.
We all enjoy spending our time on this project but it's time that Seti give's us something back.
Any thoughts on this would be appreciated.

Cheers

Bill

---

We have a long long way to go.

The galaxy is just so damn big! and light travels relative to it's size, very slowly.

It's not just distances, but timelines also.

For all we know there might have been a civilisation that had been sending out a signal for a million years or more but then stopped (for any number of possible reasons).
If the signals reaching us stopped only 100 years ago, we would never know about it.

---

Join TeamACC

Sometimes I think we are alone in the universe, and sometimes I think we are not. In either case the idea is quite staggering.

No end in sight. If we continue to find nothing, the search will expand and grow more sophisticated. On the other hand, if we do find someone, then that will prove that other civilizations can and do exist, and that they can be detected, and that the whole idea is not so ridiculous, and who knows what else might be out there. Then, SETI would become not only politically viable, but essential. The floodgates would open, and government funding would flow like Guinness on St. Patrick's day. We would build dishes to make Arecibo look like a bird bath.

---

No end in sight. If we continue to find nothing, the search will expand and grow more sophisticated. On the other hand, if we do find someone, then that will prove that other civilizations can and do exist, and that they can be detected, and that the whole idea is not so ridiculous, and who knows what else might be out there. Then, SETI would become not only politically viable, but essential. The floodgates would open, and government funding would flow like Guinness on St. Patrick's day. We would build dishes to make Arecibo look like a bird bath.

I agree with you on this one. Space supposably does not have and end. If it does go on forever and ever then we are most certainly not alone. If we have found nothing, which is the case so far, that likely (and the odds are in our favor) that the nearest civilization is very very very very very far away. And when we do detect one or communicate with one, then we WILL need a bigger better telescope, and we would be talking like hundreds of Areciboos.

---

"By faith we understand that the universe was formed at God's command, so that what is seen was not made out of what was visible". Hebrews 11.3

I agree with you on this one. Space supposably does not have and end. If it does go on forever and ever then we are most certainly not alone. If we have found nothing, which is the case so far, that likely (and the odds are in our favor) that the nearest civilization is very very very very very far away. And when we do detect one or communicate with one, then we WILL need a bigger better telescope, and we would be talking like hundreds of Areciboos.

I think that a radio telescope (or even a transceiver) purpose-built for interstellar communication would be mounted on three or more asteroids, roughly equidistant about the Asteroid Belt, transmitting their signals to a central base where the signals are phase-adjusted and combined into one stream that then gets corrected for Doppler shifts and the like.

Perhaps free-floating platforms a few A.U.'s above the Sun's magnetic poles would be more practical. Something that would eliminate athospheric interference and make Doppler/Gaussian shifts very predictable.

In any case, not a trivial expense.

---

No animals were harmed in the making of the above post... much.

I agree with you on this one. Space supposably does not have and end. If it does go on forever and ever then we are most certainly not alone. If we have found nothing, which is the case so far, that likely (and the odds are in our favor) that the nearest civilization is very very very very very far away. And when we do detect one or communicate with one, then we WILL need a bigger better telescope, and we would be talking like hundreds of Areciboos.

I think that a radio telescope (or even a transceiver) purpose-built for interstellar communication would be mounted on three or more asteroids, roughly equidistant about the Asteroid Belt, transmitting their signals to a central base where the signals are phase-adjusted and combined into one stream that then gets corrected for Doppler shifts and the like.

Perhaps free-floating platforms a few A.U.'s above the Sun's magnetic poles would be more practical. Something that would eliminate athospheric interference and make Doppler/Gaussian shifts very predictable.

In any case, not a trivial expense.

It would be interesting to see. Although I agree when you say we need something that moves more or "free floating devices" but I would say somewhere like the moon would be good for starters and testing. Afterall this would be a project requiring manpower. The Moon is not too much closer to anything no, but It has a lot of space on it. Satillites are a good idea but we would be talking about thousands probably.

---

"By faith we understand that the universe was formed at God's command, so that what is seen was not made out of what was visible". Hebrews 11.3

It would be interesting to see.

Completely off topic, but the difference in the photos of your avatar and your profile is striking. I've never seen such a 5 o'clock shadow :-)

---

No animals were harmed in the making of the above post... much.

It would be interesting to see.

Completely off topic, but the difference in the photos of your avatar and your profile is striking. I've never seen such a 5 o'clock shadow :-)

LoL...I thought the pic was updated? Hmmm...I will have to change that ..brb ;-)

---

"By faith we understand that the universe was formed at God's command, so that what is seen was not made out of what was visible". Hebrews 11.3

It would be interesting to see.

Completely off topic, but the difference in the photos of your avatar and your profile is striking. I've never seen such a 5 o'clock shadow :-)

I am getting me in a blue shirt looking away from the camera?

---

"By faith we understand that the universe was formed at God's command, so that what is seen was not made out of what was visible". Hebrews 11.3

I am getting me in a blue shirt looking away from the camera?

Yes, that's the picture in the profile... I was comparing it to your avatar, which is considerably hairier.

---

No animals were harmed in the making of the above post... much.

I am getting me in a blue shirt looking away from the camera?

Yes, that's the picture in the profile... I was comparing it to your avatar, which is considerably hairier.

Ah. LoL. Star wars is my Fav Movie ever...All of em ;-)

---

"By faith we understand that the universe was formed at God's command, so that what is seen was not made out of what was visible". Hebrews 11.3