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interesting signal in 2010-08-13-blank06_1422_1 setiQuest observation data

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robackrman
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[no-glossary] This signal found in setiQuest observation data 2010-08-13-blank06_1422_1 has characteristics of a traditional sought for ETI signal: narrow (~1Hz), weak, precise, and apparently Doppler drifted. The plot, which has no labels, is ~1Hz/pixel horizontal and 734 seconds (~12 min.) vertical. The DADD algorithm would easily detect this signal. I wonder, if it had been observed by SonATA, if SonATA would follow up on this signal or find some criteria to reject it? [/no-glossary]

herpy
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Joined: 2010-08-27
Posts: 65
Here is one that looks

Here is one that looks similar to me.  It is all the way at the bottom center of the plot kinda hard to see.

Looks dopler shifted to me because it is straight and slanted.  This is the first streak I have seen that was straight.  

It looks like it is slanted to much to be doppler shift though. 

http://imgur.com/0ZGAP

herpy
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Posts: 65
http://imgur.com/JnoPm the

http://imgur.com/JnoPm

the dots and the slash are still alone after going though all those data sets.

I guess it probably is just intermittent RFI.  It seems every other signal that isn't short lived is RFI.  

Here is a smooth wavy signal but it is in a area with a lot of RFI so it is probably RFI.
The blue and red circle is the box the picture is from.

http://imgur.com/RpOBB

Now I understand why short of a spectrogram picture there really isn't anyway to tell if something is interesting without the three beam data because it could just be intermittent RFI.

herpy
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Posts: 65
Here is one that seems to be

Here is one that seems to be in the data set 16 times.
http://imgur.com/a7Om5
 
The weird thing is it seems to be spaced out mostly the same.
 
65304
65301
65301
522424
65303
457118
326518
65299
65304
1240752
65304
587719
522426
718332
65302
those are the hz between the ones I could see.
It is probably exact but I just didn't try to hard to get the right pixel.
 
 
 
Here is the link to all the pictures of the signals I saw in that data set.
http://dl.dropbox.com/u/56988145/2010-09-24-exo219_1-8bit.zip
It doesn't appear to be obvious RFI to me and it has that slant thing going on.

Dave Robinson
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Posts: 196
Is it pulsing?

That looks an interesting signal; I am afraid my eyesight isn't as good as it once was, and find your colour scheme slightly difficult to see. However the diagonal streak definitely looks like a tone with a Doppler gradient, suggesting that it is not an earth based interference signal; however I get the impression that the signal is pulsing on and off about 3 times in your time frame. and it looks like it could be a fairly regular pulsation - it might of course be that the signal just disappears into the noise; it looks like we aught to make a more detailed look at this signal

Regards

Dave Robinson

robackrman
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another interesting signal

I applied the following operations to Herpy's recent image: desaturate, invert (black <--> white), contrast, and then flip vertically.  Dave, can you see the signal better?  I also added a red guideline (left of the signal) which demonstrates that the signal, although drifting, is frequency stable.  This is an interesting signal.   It has the characteristics of the classic ET signal which has been sought by the SETI Institute and others.

I flipped the image vertically so that the Doppler drift would be like that seen in SonATA.

The signal could be pulsing as Dave suggested.   Another possibility is that the signal is linearly polarized and rotating its polarization angle against the linear polarization of the feed.  Unfortunately, the ATA has never achieved full Stokes parameters (recording both calibrated linear feed inputs), so we have no way that I can think of to experimentally determine this.

I wish there were more interplay between the SETI Institute staff and the forum members: myself, Dave, Herpy, and others.  There would be more excitement for the community if we could have a sliver of time for some reobservations even if the signals in question were deemed, for whatever reason internally, not likely to be fruitful.

herpy
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Posts: 65
I am seeing the signal again

I am seeing the signal again in another data set so it is RFI.  

Dave Robinson
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Interesting RFI

First thanks Rob, your post processing of Herpy's picture made it much easier for me to see, I am very grateful to you for going to this effort.

I am not sure it makes sense to just put this signal down to RFI. First it is so linear in terms of Doppler gradient indicates that the source is accelerating wrt ATA, which suggests that it is probably not in the Data acquisition system. Secondly as Rob say's this is exactly the sort of signal we are looking for, so if it is a bogey, we aught to go to have a crack at trying to identify it. The most likely situation is that it could be one of our own spacecraft. Well we know what the telescope was pointing at in this instance, and in the other times you have found it. The signal is clearly very low in amplitude, as it is so close to the ambient noise level. It could of course be some form of harmonic from a much stronger signal, but this should show up in other regions of the Waterfall.

We know where it is in the sky, we know its relative motion wrt ATA, we know the times at which it was visible and the frequency it was transmitting, so I would have thought that someone who knew their orbital mechanics could have a good crack at identifying this so it can be labelled a bogey - if that is what it is.

Regards

Dave Robinson