A question for SETI

Phil
Phil
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RE: RE: What's with the

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What's with the system double posting anyway?

Phil

Maybe it a Seti conspiracy?

I knew it!!

Phil

I thought I was wrong once, but I was mistaken.

Chris S
Chris S
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RE: Imagine a superior

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Imagine a superior civilization making it's decision on whether to let us live or not based on our transmissions of "reality" TV.


C'mon, they would take one look at the Seti politics thread and nuke us for our own good!!!

Waiting for Godot & salvation :-)

Why do doctors have to practice?
You'd think they'd have got it right by now

David S
David S
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RE: RE: A couple of

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A couple of 'wrenches' to throw at you...us sending a message, and them receiving it, is a LONG WAY from them landing on the Earth and eating us!! If they can ALREADY get here, I think it's WAY too late to try and hide!! Good grief we are sending messages to Pluto and back, and have been sending them to Mars for over a decade now. Voyager is either close to, or is actually in 'Deep Space' right now, and we STILL talk to it!!

Yeah, I think some folks are trying to close the barn door after the cows have already made their escape. The earth is one big ball of RF radiation. Imagine a superior civilization making it's decision on whether to let us live or not based on our transmissions of "reality" TV.

Everyone load your BB guns. It's gonna get rough...:-)

Phil


One of Dr. K's points is that the current RF blob around us would only be detectable out to a very few light years, whereas what's being debated is a directed beam transmission that would be easily detected by whoever it was aimed at hundreds of light years out. Like the difference between seeing the spill of a flashlight vs. a laser pointer on a dark night. You can see the laser beam from a lot farther away, but only if it's pointed very close to you.

David

Miserable old git
Patiently waiting for the asteroid with my name on it.

mikey
mikey
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RE: RE: RE: A couple of

Quote:
Quote:
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A couple of 'wrenches' to throw at you...us sending a message, and them receiving it, is a LONG WAY from them landing on the Earth and eating us!! If they can ALREADY get here, I think it's WAY too late to try and hide!! Good grief we are sending messages to Pluto and back, and have been sending them to Mars for over a decade now. Voyager is either close to, or is actually in 'Deep Space' right now, and we STILL talk to it!!

Yeah, I think some folks are trying to close the barn door after the cows have already made their escape. The earth is one big ball of RF radiation. Imagine a superior civilization making it's decision on whether to let us live or not based on our transmissions of "reality" TV.

Everyone load your BB guns. It's gonna get rough...:-)

Phil


One of Dr. K's points is that the current RF blob around us would only be detectable out to a very few light years, whereas what's being debated is a directed beam transmission that would be easily detected by whoever it was aimed at hundreds of light years out. Like the difference between seeing the spill of a flashlight vs. a laser pointer on a dark night. You can see the laser beam from a lot farther away, but only if it's pointed very close to you.

Assuming you can travel at or near the speed of light you would HAVE to have some kind of detection system or you would run into something long before you could see it. That detection system would most likely pick up our transmissions a LONG way off, no matter what kind we are giving off. The story has always been that light, radio signals etc keeps going in Space until they hit something to stop or alter it's path, has that changed? If not despite being as slow as a no legged dog, the stuff we are sending is STILL going somewhere.

David S
David S
Joined: 6 Dec 05
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RE: RE: RE: RE: A

Quote:
Quote:
Quote:
Quote:
A couple of 'wrenches' to throw at you...us sending a message, and them receiving it, is a LONG WAY from them landing on the Earth and eating us!! If they can ALREADY get here, I think it's WAY too late to try and hide!! Good grief we are sending messages to Pluto and back, and have been sending them to Mars for over a decade now. Voyager is either close to, or is actually in 'Deep Space' right now, and we STILL talk to it!!

Yeah, I think some folks are trying to close the barn door after the cows have already made their escape. The earth is one big ball of RF radiation. Imagine a superior civilization making it's decision on whether to let us live or not based on our transmissions of "reality" TV.

Everyone load your BB guns. It's gonna get rough...:-)

Phil


One of Dr. K's points is that the current RF blob around us would only be detectable out to a very few light years, whereas what's being debated is a directed beam transmission that would be easily detected by whoever it was aimed at hundreds of light years out. Like the difference between seeing the spill of a flashlight vs. a laser pointer on a dark night. You can see the laser beam from a lot farther away, but only if it's pointed very close to you.

Assuming you can travel at or near the speed of light you would HAVE to have some kind of detection system or you would run into something long before you could see it. That detection system would most likely pick up our transmissions a LONG way off, no matter what kind we are giving off. The story has always been that light, radio signals etc keeps going in Space until they hit something to stop or alter it's path, has that changed? If not despite being as slow as a no legged dog, the stuff we are sending is STILL going somewhere.


If it's not in a very tight beam, it quickly disperses to the point that there isn't enough signal strength to receive.

David

Miserable old git
Patiently waiting for the asteroid with my name on it.

Mike Hewson
Mike Hewson
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Some of the radiation is

Some of the radiation is absorbed, but the key point is coherence of the signal. What is the real penalty with inverse square is the reason for that behaviour : for a given subtended solid angle the area grows by the square of the distance. That's pretty savage. Also a listener has to distinguish our emissions from whatever else is going on, and in a fashion that resembles the original transmission. As the photons spatially disperse one would need an awfully big receiver to catch enough to analyse successfully.

Cheers, Mike.

( edit ) In fact TV is a good example to quote. The reason why I Love Lucy doesn't carry is partly the cosmic microwave background. If you leave the TV on but un-tuned to any known transmitting channel then some of the hash on the screen is due to CMB photons.

I have made this letter longer than usual because I lack the time to make it shorter ...

... and my other CPU is a Ryzen 5950X :-) Blaise Pascal

mikey
mikey
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RE: Some of the radiation

Quote:

Some of the radiation is absorbed, but the key point is coherence of the signal. What is the real penalty with inverse square is the reason for that behaviour : for a given subtended solid angle the area grows by the square of the distance. That's pretty savage. Also a listener has to distinguish our emissions from whatever else is going on, and in a fashion that resembles the original transmission. As the photons spatially disperse one would need an awfully big receiver to catch enough to analyse successfully.

Cheers, Mike.

( edit ) In fact TV is a good example to quote. The reason why I Love Lucy doesn't carry is partly the cosmic microwave background. If you leave the TV on but un-tuned to any known transmitting channel then some of the hash on the screen is due to CMB photons.

So you are both saying Seti is probably NEVER going to work as the dish is too small?

anniet
anniet
Joined: 6 Feb 14
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RE: RE: Some of the

Quote:
Quote:

Some of the radiation is absorbed, but the key point is coherence of the signal. What is the real penalty with inverse square is the reason for that behaviour : for a given subtended solid angle the area grows by the square of the distance. That's pretty savage. Also a listener has to distinguish our emissions from whatever else is going on, and in a fashion that resembles the original transmission. As the photons spatially disperse one would need an awfully big receiver to catch enough to analyse successfully.

Cheers, Mike.

( edit ) In fact TV is a good example to quote. The reason why I Love Lucy doesn't carry is partly the cosmic microwave background. If you leave the TV on but un-tuned to any known transmitting channel then some of the hash on the screen is due to CMB photons.

So you are both saying Seti is probably NEVER going to work as the dish is too small?


*dull thud* ....

*weak distant voice* ... can you people PLEASE give me some warning before you come out with stuff like that! *pause... greatly extended one* do you have any idea *puff wheeeeeeeeeeeeze*

...how long it takes me to get up off the floor these days? No... and now I've forgotten what I was going to say so I'm going to have to go back and read EVERYTHING again...

*scroll down page midst LOUD grumbling*

Quote:
...dish is too small?


*dull thud* .... *weak distant voice* ...

oh good GRIEF!

I'm uncomfortable...

...you know... with the hypocrisy :)

...that it's alright for us lot to eavesdrop and give ourselves plenty of time to plot a paranoid response along the lines a dangerous and somewhat deranged species would resort to... *pause* ...

oh... I get it now...

*blink*

well... if we can't rise above our only frame of reference - ourselves, I'm a trifle... you know... disappointed... and can't help wondering how ethical it is for us to spy on our neighbours under those circumstances. *cast disappointed gaze - perfected by years of motherhood - around thread* :)

We have enough weapons to obliterate ourselves many times over. What happens if we do find a signal - would we subtly reposition our weapons so that they're not pointing at each other - just in case - or make a whole new set pointing straight up? 'Scuse me for a moment ... *clump to area of thread that promises a soft landing*

Y-e-e-s... just as I thought *dull thud* ... oh... should have fallen the other way...

:)

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