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- From: mg19768@gaia.swipnet.se (Tommy ClarΘn)
- Newsgroups: alt.paranet.ufo
- Subject: Re: Radiowaves?
- Date: 18 Jun 96 15:57:14 +0100
- Organization: -
- Lines: 50
- Message-ID: <2304.6743T957T712@gaia.swipnet.se>
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-
- >Tommy ClarΘn (mg19768@gaia.swipnet.se) wrote:
-
- >: One thing that I find a bit strange is that we are not picking up any
- >: radiowaves from other civilizations in universe.
-
- >: If a civilization reached the point of technology where they can travel
- >: between the starsystems, the must has been sending out radiowaves for
- >: at least a couple of hundred years, maybe thousands. How come there
- >: spacecrafts reach our solarsystem before there radiowaves do. Unless
- >: they discovered space traveling before they discovered radiosignals,
- >: which I doubt.
-
- >: What does you highly educated people think, is our receivers not sensitive
- >: enough to pick it up, or is it possible that other civilization discovered
- >: entirely different ways of transmitting messages.
-
- >Here's a repost of one reason why we won't hear them. . .
-
-
- >The formula for EMF propagation is P(ower detected)*4Pi(D)istance)^2 =
- >ST(rength of source signal.
- >Using 3.0E8 mps as the distance light/EMF travels in a second you can get a
- >distance of 9.23E16 meters at 10LY. This is relatively close.From a
- >conversation with Dr. Beck of the PHOENIX project he told me that they
- >currently can detect signals on the level of 1.3E-27 watts. Plugging in the
- >numbers you get a source strength of 139,099.068.68 Watts of power at the
- >source. 139 Megawatts is a LOT of power. If you use a typical 20dB gain
- >antenna you could narrow the beam and lessen the power to 1.39 Mega watts.
- >And SETI is looking at stars in
- >50LY range, again from a talk with Dr. Beck. So the power needed is 69.5 Mw
- >for use to detect it. We have no need for such signal strength, I don't even
- >think HAARPo will use that much power. Why would we suspect an ET race to be
- >wasting such power on local communications? It just doesn't make any sense to
- >expect these ET's to be doing things differently than us. After all, SETI
- >assumes that they will use radio waves for communication. . .
-
- >Garry (%^{>
-
- I read somewhere that because our radiosignals have reach 40-50 LY out in
- space, the earth would shine as a small sun in a radiotelescope, so I
- thought that radiowaves just goes on for ever out there.
-
- But this is obviously not the case.
- Thank's, I appreciate your good answer.
-
- But this generates a new question. How did they find us?
-
- Tommy C
-
-