I think about the kind of antenna gain and transmit power needed to generate a signal from outside our galaxy that we could detect and differentiate from stars and figure anyone that could would know better than to try and contact a bunch of primitive apes in the first place.
Its been estimated that two Arecibo type instruments could communicate with each other across the galaxy, so I donât think the gain issue is too much of a problem.
But I wish the article gave the location in the sky of the sources. Two alien civilisations behaving in a similar manner would be highly unlikely.
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Then thereâs always:
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What is your source for this binary âmessage?â
What, assuming that Arecibo-type instruments (and the society providing their operators) would remain operational for 100000 to 120000 years implied by that statement? Claim is laughable on its face.
Damn it! Well I feel rather gullible. Was really kind of hoping it was true X-D
No worries 
I only learned that trick recently while playing Bad Ass Dragons of the Wasteland here on the BBS.
I would like to see a citation on the technical issue of gain.
And the phrasing of [quote=âMichael_R_Smith, post:22, topic:38037â]
communicate with each other
[/quote] implies a conversation.
But a gentler reading of âcommunicationâ â allowing it to mean simply that one could detect a signal sent by the other â does not require that both be in operation for the entire time that signal is crossing the intervening space.
Once the signal is sent out, the sending society can collapse and the instrument can crumble to dust, leaving plenty of time for the receiving society to advance from upper paleolithic technology all the way to the capacity to receive and comprehend the Arecibo Message.
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I am only referring to the characteristics of the antennas, receivers and transmitters, not the operators and it does assume that both can listen more or less continuously.
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Correct me if Iâm wrong here, but I donât think the article was implying that the messages were necessarily coming from two different sources. They did say that two radio telescopes on opposite sides of the planet detected the radio bursts, but they could still have been picking up one source depending on how they are positioned relative to it, and also donât forget that the Earth rotates (am I missing something here?) As for giving the location in the sky of the sources, they specifically state âright now, astronomers have no idea whatâs causing these bursts or where theyâre coming from.â Yes?
From the same movie, a clip I canât watch dry eyedâŚ
Yeah Astronomers know that. Most radio telescopes are directional so detecting a signal means you know the altitude and azimuth in the sky as well as the time of detection. This gives you an absolute coordinate in the sky but the article didnât actually say the signals come from the same part of the sky. Maybe the uncertanty in location is about the distance. It could be a noisy amplifier 10^0 metres away or a quasar 10^18 metres away.
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