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Galactic anticenter

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Anders Feder
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setiCloud has some 40 GB of data from observations of the galactic anti-center. What is the motivation for studying the galactic anti-center in SETI? Are there even any stars there?

sigblips
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My guess is the thinking is

My guess is the thinking is that the galatic center is the hub of civilization, so looking anti-center would intercept any "outpost" communications directed towards the center. This means that the "outpost" would have to be inline with us and the galactic center but that is better odds than looking randomly around the sky.

I don't see this 40 GB of data in the data/API section. Is there any way to download this data from setiCloud so that I can analyze it in baudline? So far setiCloud in its current implementation is not of any value to me.

robackrman
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The "outpost" explanation is

The "outpost" explanation is correct.  Looking at the anti-center is an alternative to looking at, or near, the galactic center which is not above the ATA horizon during the times for which setiquest observations are currently scheduled.

Here are the URLs for the original anticenter data which was fed into CloudAnt:

184.73.186.167/download/2010-05-07-galanticenter-1/
184.73.186.167/download/2010-05-07-galanticenter-2/
184.73.186.167/download/2010-05-07-galanticenter-3/
184.73.186.167/download/2010-05-07-galanticenter-4/
184.73.186.167/download/2010-05-07-galanticenter-5/

Anders Feder
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Okay. But as far as I can

Okay. But as far as I can tell there are no (observable) stars in that exact direction. So the ETI's would have to either use some strong transmitters with wide beams or be picking target stars close to the position of the galactic center on their sky?

Is there any way to tell from the metadata what the diameter of the synthesized beam was in these observations? Or is it fixed?

Very interested to see what you can find sigblips, since especially the fifth of the data sets that Rob linked scored high on the KLT test and somewhat high in the kurtosis test. There is definitely something there and it is increasing in magnitude over the five sets. Could be RFI since they were recorded at consecutive times - from 2010-05-07 11:30 to past 2:43. But it would still be valuable to see what kind of signal gives this result.

robackrman
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The synthesized beam is ~ 5

[no-glossary]
The synthesized beam is ~ 5 arcmin diameter at 1420 MHz.  About 1/3 the width of the 0.25 degree sky chart you referenced.  The synthesized beam narrows with increasing observation frequency.
I am interested as well in the results from sigblips.
Note, from the metadata, the anti-galactic observations were conducted at various frequencies.
[/no-glossary]

Anders Feder
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Ah, great. This chart should

Ah, great. This chart should be more representative then. There is at least some 239 stars there according to USNO-A2.0.

sigblips
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Thanks for those URLs. Are

Thanks for those URLs. Are there other data directories that haven't been exported to the http://setiquest.org/join-the-quest/data-api/getting-data webpage? Is there any way to find them?

Anders Feder
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This information can now be

This information can now be found through Vis.

sigblips
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Wow, that's pretty cool.

Wow, that's pretty cool. Thanks.

gerryharp
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outpost and available now

Hi All
The "outpost" theory is what we had in mind when collecting data on the galactic anti-center. Very good sleuthing!
There were 5 collections on the galacitc anti-center. As you can see from the notes in the files, collections 1, 2 and 5 are good, collections 3 and 4 were aborted b/c we discovered some or other technical problem.
#1 is taken at the PiHI frequency. (a la Carl Sagan).  We believe this is a good band because A) every civilization will know both the frequency of the HI line and the number PI and B) it is arguable that no self-respecting ETI group would pollute the extremely important HI band with radio frequency interference. Even on earth, 1421 MHz is a "protected band." Finally, C) there has been very little SETI work at Pi * HI because the receivers for such signals are not generally available. It is new turf!
#2 was taken at 3991 MHz, at the direct request of Jill Tarter. This is what's known as a  "bad" frequency band. So we DON'T expect to find a SETI signal here and wouldn't believe it if we did. This band is so full of myriad RFI junk that is all man-made that usually we don't even bother to try to observe in this range. But Jill makes an important point -- in order to know the enemy ("and he is us"), we have to study it. Furthermore, we can learn a lot about how ETI may choose to transmit their signals by studying the way humans transmit signals. Most of the crud in this band is C-band TV satellites. A sufficiently motivated amateur might be able to decode some TV signal; if they have the right kind of decoder.
#5 is taken at plain old vanilla 1422 MHz. It is a clean band and if you generate a frequency power spectrum from this data you will see a strong HI signal. We have not attempted any further analysis of this data, yet, but we will soon so you better get crackin'!
Cheers and have fun,
Gerry
 

hartzell
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Maybe just to get some less

Maybe just to get some less noisy samples? 

A galactic-center vs. anti-galactic-center might be the equilivent to the RF cold-sky vs. sun-noise test...