The SETI@home algorithms are quite good and take many factors into account. Yes, they are aware of what you describe as "Fade-In and Fade-Out signals". They also account for Doppler shift in signals.

What is this?; USN AW

US Navy something maybe?

By the sounds of things, you possibly have quite a bit of experience in radio transmission and detection analysis?

John.

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Does Seti look for any type of carrier wave. In a such a long distance signal the guts of the message would be lost to background noise. The carrier wave still exists. Sort,ve like a cb band and the signal would be weak but a voice can still be heard. If there is such a species that create a radio type of communication we would only be able to hear leaked messages. The distance involved nothing would be left of very powerful signal let alone normal communication. Most stars with planets are more than 5 light years. At speeds we can attain about 60000 mph to reach the nearest star would take 73000 years one way. That alone is a sobering thought. If ET is millions of years ahead of us a entirely different form of communication would be used. One day man will have to leave our star system to survive. Our star will someday die and man will have to beat the distance barrier to find other inhabital planets.

is a Best Triplet Power value of 12.86 30.9953 of interest, keeps repeating on setihome graph, thanks

A signal is only of interest if it can be proven that it is not an "ordinary" signal,, and if it can be heard from the same part of the sky on different observation dates. There are many sources of "interference", or unwanted signals that are picked up. These are stored in a database and each new signal found is compared against it to see if it matches one of the "known" signals. Each signal has a "signature" or "pattern" unique to it. (I'm an amateur radio operator, and we have a computer program that you can feed a signal into and it will identify the particular radio out of the millions that are produced that sent it!)
But that's getting away from your question.
A very strong signal is probably not going to be one we are interested in. Much more likely would be one that is very weak, even buried in the background noise, but one that is only received when the antenna is pointing at one certain spot in space. Each work unit produced has the exact time and the position of the telescope stored when it was recorded. This information is used to determine a lot of the "bogus" signals. If a particular signal occurs at regular intervals regardless of where the telescope is pointing that is a clue that it's not a "lgm" (little green man!) but rather a source closer to the telescope.

So the short answer to your question is "probably not".

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Jim

Some people plan their life out and look back at the wealth they've had.
Others live life day by day and look back at the wealth of experiences and enjoyment they've had.

Jim R. wrote the following:

"A signal is only of interest if it can be proven that it is not an "ordinary" signal,, and if it can be heard from the same part of the sky on different observation dates".

If some of the numbers are supposed to be from the skies, what then would the numbers of interest likely appear to be (spike, pulse, gaussian, triplet) ?

Is it all numbers, or could there be something else as well? What constitutes the breakpoint or difference between the ordinary result and the one that might be of interest?

Right now there is not much showing up, but what about the past (and possibly the future)? Could numbers change again?

Thanks!

thank you for insigthful anlysis, would like your opinion on the following sethihome numbers

New Pulse Power: 8.15 Period 24.3270 score 1.10
are those of any curiosity


where in the sky is 18hr 51' 54'RA + 13 deg 5' 2' Dec

i think those coordinates are close to the Auriga constelation

If your coordinates are right, the constellation should rather be Aquila and not Auriga. The constellation of Ophiuchus borders to the west and south of this area.

Personally, I have no knowledge about what is contained in the database, or of the possible significance of any figures. Any of them that show any type of signal at al could be of significance.
The information from every work unit processed is stored into another database, whether it contains a detectable signal or not. Periodically this database is run through a computer program that compares the information with the known signal database, and the master database for every other work unit processed from the same area of the sky. Each signal is assigned a neutral "quality" factor when it is discovered. When the database is evaluated for possible candidate signals which (until the "nitpicker" or "Near Time Persistancy Checker" program comes online) has only been run two or three times, it will compare the candidate signal with the known object database. If they match the quality factor goes down. If they don't it stays the same. Then when it is compared with the rest of the units and it finds a match the "q" factor goes up. After the process is completed the signals with the highest "q" are examined to determine if there is a possible manmade source. If it does it's logged into the known source database. If not it's put into a pool for real time reexamination. (EDIT) the "Q" factor has nothing to do with how strong or weak a signal is. It is determined by the shape and charactistics of the signal and whether it compares to a known signal either from the "identified" signal database or a signal in other work unit results. (It's been a while since I've been able to read the exact procedure for this quality check so I may be off on many of the details, but the idea for the Q check is basically right.)

(I remember reading that once they had an unidentified signal that only occurred around noon each day, and occurred regardless of the direction the telescope was pointing. After checking all of the equipment for possible problems, and doing a through survey of the signals in the immediate area, checking for a possible new satellite launch, new airline flight etc. it was found that one of the employees had developed the habit of going up on a hill overlooking the telescope to eat his(her) lunch and they took a transistor radio with them!)

So without having access to the databases, and without running the comparison programs there's no way to say what is a "good" signal or a "bad" one. As I mentioned in my last post, any signal at all, regardless of the numbers, is significant until it is run through the computer programs to classify it.

While it's exciting to look at the display or through the program output and see a huge spike and think "this is it, an alien signal", the reality of it is that the bigger and cleaner the signal, the less chance it has of being what we're looking for. It's like using a radio to try to hear a station far away. When you're listening for it's signal you don't tune into the strongest signal and say "here it is, I've found it". That is usually a nearby station that you don't want to hear. Instead you listen for the very weak noisy signals that you can just barely hear. We are in the same situation. Unless an alien spacecraft parks itself somewhere nearby, we won't hear a good strong signal from them. We will hear the weakest of signals that are barely detectable through the natural noise level of space (and the surrounding earthly area.)

When you see that huge strong spike you should start wondering "what airplane flew over? or "Could this be a new satellite? or "Has someone went up on the hill to eat lunch with their radio" (hehe) again?". So unless they hit us with a concentrated beam using the total output power of several solar systems, if and/or when we do get that "wow" signal, we at home probably wouldn't ever notice it.

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Jim

Some people plan their life out and look back at the wealth they've had.
Others live life day by day and look back at the wealth of experiences and enjoyment they've had.

thank you very much for you detailed anlysis and highly informative explanation. I will just keep checking and who knows maybe that WOW signal might be in the background noise. Just curious, is the Aracibo radio telescope antena positioned to receive radio signals from the direction of Sagitarius. Sagitarius is closer to the galactic center, hence higher star formation, with perhaps higher probability of stars having habitable planets. How can be Gliese E be habitable if it is permanently locked with it its star, on side allways on the day side and the other on the night side. Are plate tectonics even possible in such an envoriment, GliseE does not rotate as far we know, it might not have an active magma.

I'm not sure the exact position of the star/planet you refer to but if it lies within the limited area of the sky that the telescope can track then the telescope can see it. Arecibo, due to it's construction, can only see a portion of the sky about 40 degrees wide. Maybe someone on here that has more knowledge of astronomy than I do can tell you for certain.
I'm not an astronomer, and I'm certainly not an exobiologist so I can't begin to answer your other questions. At this point I don't think even they could! Mercury is the only planet that lacks a "daily" rotation that we have been able to study at all, and without an atmosphere there's no possibility of life as we know it. With an atmosphere, who knows?

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Jim

Some people plan their life out and look back at the wealth they've had.
Others live life day by day and look back at the wealth of experiences and enjoyment they've had.

[…] Just curious, is the Aracibo radio telescope antena positioned to receive radio signals from the direction of Sagitarius. […]

No, Arecibo can’t see as far south as Sagittarius; its declination range is only from about –2° to +38° (±20° from its own latitude), because it can’t be ‘aimed’ more than about 20° below the zenith. See Where in the sky? from the “Classic” screensaver description. Some portions of the Milky Way are covered, though, in the Aquila–Cygnus and Taurus–Gemini regions.

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Einstein@home is getting data from the Parkes radiotelescope in Australia in its search of binary pulsars. Parkes should cover also the galactic plane, where pulsars are more abundant.
Tullio

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thank you for your response, so the receiver at Aracibo is not capable to be pointed toward Sagitarius where suposedly the WOW signal originated from, any thoughts on that. Can pulsars,magnetars simulate a credible radio signal.

The S@h strategy is random sweeping, as opposed to the directed listening some other SETI projects have undertaken. OTOH should we find something especially interesting, I imagine specific follow-up observations could be arranged, whether by Arecibo or elsewhere.

AFAIK the signals from pulsars, which the E@h project can detect (see the list), are quite distinctive and unlikely to make a 'false positive' here. Assuming, that is, that ET has the sense not to build a beacon that simulates a pulsar!

is SHGb02+14a radio source possible indication of a pulsar