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Breakthrough Listen publishes first analysis of 692 stars in ET search

universetoday.com

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Re: Breakthrough Listen publishes first analysis of 692 stars in ET search

#2
"The Green Bank Telescope searched for these signals using its “L-band” receiver, which gathers data in frequencies ranging from 1.1 to 1.9 GHz ... they conducting three five-minutes observation periods, while also conducting five-minute observations on a set of secondary targets"

Does this seem like a really short timescale to anyone else?

Of course, anything on human timescales is but the blink of an eye on geological, never mind astronomical timescales, but it still fells like you'd have to get awful lucky to catch something in just the 5 to 15 minutes you happened to be listening on a narrow range of radio frequencies.

Re: Breakthrough Listen publishes first analysis of 692 stars in ET search

#3
From what I have read, most of this SETI data processing involves very long FFT to channelize down to 1 Hz BW. However, assuming any alien signals would be like our digital comms, those signals are pseudo noise like, so using very narrow bandwidths just reduces the signal too. These narrow bandwidths would only be good for CW signals?

Re: Breakthrough Listen publishes first analysis of 692 stars in ET search

#4

"The Green Bank Telescope searched for these signals using its “L-band” receiver, which gathers data in frequencies ranging from 1.1 to 1.9 GHz ... they conducting three five-minutes observation periods, while also conducting five-minute observations on a set of secondary targets" Does this seem like a really short timescale to anyone else? Of course, anything on human timescales is but the blink of an eye on geologi…

Yeah, I have read to detect a transmission from several light years, it would take a transmitter like Aeroceibo. Also must assume the alien politicians would fund it long enough.

Re: Breakthrough Listen publishes first analysis of 692 stars in ET search

#6
The data is analyzed on a distributed network. You can download the app and have it run in the background or as a screensaver. If ET is found, they promise to credit the computer owner that actually finds it. Just think, you might be the one!

https://seti.berkeley.edu/participate/

I have been doing this since 2005, have processed over 5 million units, and am in the 98th percentile worldwide.

Re: Breakthrough Listen publishes first analysis of 692 stars in ET search

#7
post #3

From what I have read, most of this SETI data processing involves very long FFT to channelize down to 1 Hz BW. However, assuming any alien signals would be like our digital comms, those signals are pseudo noise like, so using very narrow bandwidths just reduces the signal too. These narrow bandwidths would only be good for CW signals?

If I recall my EE schooling correctly, the 1Hz resolution bandwidth significantly reduces the noise floor of the receiver, and this allows you to resolve smaller signals from the noise. Also, assuming it is sweeping, having a digital signal with greater bandwidth is no problem to find.

Re: Breakthrough Listen publishes first analysis of 692 stars in ET search

#8
post #3

From what I have read, most of this SETI data processing involves very long FFT to channelize down to 1 Hz BW. However, assuming any alien signals would be like our digital comms, those signals are pseudo noise like, so using very narrow bandwidths just reduces the signal too. These narrow bandwidths would only be good for CW signals?

If I recall my EE schooling correctly, the 1Hz resolution bandwidth significantly reduces the noise floor of the receiver, and this allows you to resolve smaller signals from the noise. Also, assuming it is sweeping, having a digital signal with greater bandwidth is no problem to find.

Yes, EE here too, but if the signal you're trying to detect is also noise like (pseudo random), it is averaged out with the noise. That's why I'm thinking that any moderately complex signal won't be detectable. We'd have to detect a signal that aliens purposely sent out at a very narrow bandwidth; essentially seconds per bit, or even narrower.

Re: Breakthrough Listen publishes first analysis of 692 stars in ET search

#9
I hope we find some ETs. Otherwise I'm worried we're either:

- in a simulation, and they didn't bother to simulate other parts of the universe in high fidelity.

- in a zoo, and somehow we're blocked from seeing other civilizations.

I don't buy, for an instant, that in a universe of this size, we'd be the only life forms.

Re: Breakthrough Listen publishes first analysis of 692 stars in ET search

#10
post #9

I hope we find some ETs. Otherwise I'm worried we're either: - in a simulation, and they didn't bother to simulate other parts of the universe in high fidelity. - in a zoo, and somehow we're blocked from seeing other civilizations. I don't buy, for an instant, that in a universe of this size, we'd be the only life forms.

But the speed of light is kinda slow relative to the size of the universe, right?
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