Thread: radio signals

if radio waves continue to travel infinitely, you would think that if other tech societys existed in the universe they would have been flooding space with their signals and we would be inundated with their traffic. perhaps we are the first to achieve this in 13 billion years. or do these signals decay with time and distance.

Originally Posted by alwon

if radio waves continue to travel infinitely, you would think that if other tech societys existed in the universe they would have been flooding space with their signals and we would be inundated with their traffic. perhaps we are the first to achieve this in 13 billion years. or do these signals decay with time and distance.

That would be true, but that's not how it works. Intelligent Radio signals degrade as the move across space. In fact, pretty much all of Earths Radio transmissions are garbled beyond recognition before they ever leave our own solar system.

Only a very powerful transmission can go far- check out the Arecibo Message.

We use radio telescopes to listen to unintelligent radio waves from space, but that's a whole different enchilada- considering that I'm sure you are aware of radio telescopes, I can see why you would have reached the conclusion that you had.

And happy first post.

Radio waves travel infinitely, but the intensity that we can perceive decreases with the square of the distance, the same as for the light. So, if somebody is watching TV on Alpha Centauri, I am not sure we can see the show on earth.
Actually, it is easy to receive radio waves coming from the space, but, so far, they have been attributed to natural phenomenons rather that to intelligent activities. Just turn a TV antenna toward the sun and you will receive a bunch of radio waves : it doen't prove that there is somebody up there listening to music !
I few decades ago (Yeah, I getting old, I know that.), there was a great excitation because some lab have receive radio waves, from space, that seemed to be modulated. During a day or two, it was considered as possibly transmitted by some outer space civilisation. It was rapidly established that is was a natural phenomenon.

Originally Posted by caKus

I few decades ago (Yeah, I getting old, I know that.), there was a great excitation because some lab have receive radio waves, from space, that seemed to be modulated. During a day or two, it was considered as possibly transmitted by some outer space civilisation. It was rapidly established that is was a natural phenomenon.

You may be referring to the "Wow! Signal" noted by SETI. Most consider it to be a fluke, but googling up "Wow! Signal" should yield hits on reputable sites, even wikipedia.

It makes you think we could be "alone" after all.

Originally Posted by Jim Colyer

It makes you think we could be "alone" after all.

OTOH, consider our own radio 'signature'. It's only been radiating for about 90 years or so. Which means that any potential receiver would have to be within 90 lys, a miniscule distance.

Originally Posted by Neverfly

Originally Posted by caKus

I few decades ago (Yeah, I getting old, I know that.), there was a great excitation because some lab have receive radio waves, from space, that seemed to be modulated. During a day or two, it was considered as possibly transmitted by some outer space civilisation. It was rapidly established that is was a natural phenomenon.

You may be referring to the "Wow! Signal" noted by SETI. Most consider it to be a fluke, but googling up "Wow! Signal" should yield hits on reputable sites, even wikipedia.

He might also be thinking of LGM-1.

LGM-1(for Little Green Men) was the nickname given to the first pulsar detected in 1967. The regular timing of the signals raised the possibility that they were of artificial origin. A natural explanation (rotating neutron stars) was forwarded in 1968, which was followed by the detection of a second pulsar in the Crab nebula, which pretty much nailed it down as natural.

Originally Posted by Janus

He might also be thinking of LGM-1.

LGM-1(for Little Green Men) was the nickname given to the first pulsar detected in 1967. The regular timing of the signals raised the possibility that they were of artificial origin. A natural explanation (rotating neutron stars) was forwarded in 1968, which was followed by the detection of a second pulsar in the Crab nebula, which pretty much nailed it down as natural.

That sounds a lot closer than mine.
LGM-1... somehow that made me think of Odyssey...(TMA-1)

Originally Posted by Jim Colyer

It makes you think we could be "alone" after all.

Alien life probably monitored our politicians on our TV broadcasts and decided that there was no intelligent life on Earth!

Originally Posted by efbjr

Originally Posted by Jim Colyer

It makes you think we could be "alone" after all.

Alien life probably monitored our politicians on our TV broadcasts and decided that there was no intelligent life on Earth!

They should have monitored this site, instead.

He might also be thinking of LGM-1.

Yes, Janus, I think you are right ! You know my memories better than I do ! From your mail, I had some reading about LGM-1 and pulsars, a very interesting topic.
Thanks.

I seem to recall the assertion that the use of radar means that our solar system would show a detectable and clearly artificial excess of emissions in that microwave band. Not a signal but detectable at far greater distance than anything except deliberate or aimed emissions or signals.

Originally Posted by alwon

if radio waves continue to travel infinitely, you would think that if other tech societys existed in the universe they would have been flooding space with their signals and we would be inundated with their traffic. perhaps we are the first to achieve this in 13 billion years. or do these signals decay with time and distance.

That would be the infamous Fermi paradox - Wikipedia, the free encyclopedia