archive: SETI Re: [ASTRO] Encounter 2001 "Cosmic Call"

SETI Re: [ASTRO] Encounter 2001 "Cosmic Call"

Larry Klaes ( lklaes@bbn.com )
Mon, 28 Dec 1998 10:08:54 -0500

>X-Authentication-Warning: brickbat12.mindspring.com: majordom set sender
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>X-Sender: pchien@digital.net
>Date: Thu, 24 Dec 1998 18:06:10 -0500
>To: ASTRO@lists.mindspring.com
>From: Philip Chien <kc4yer@amsat.org>
>Subject: Re: [ASTRO] Encounter 2001 "Cosmic Call"
>Sender: owner-astro@brickbat12.mindspring.com
>Reply-To: Philip Chien <kc4yer@amsat.org>
>
>Let's see if I can consolodate some comments and add my 3 cents worth -
>
>Here's the clip of the press release which was posted to the [astro] list -
>
>FOR IMMEDIATE RELEASE
>Interview opportunities available
>
>Media Contact: Susan Schonfeld 914-356-6089
>or 914-371-9684
>Alternative Contact: Chan Tysor 713-522-7282
>http://www.encounter2001.com/
>
>FIRST TIME EVER OPPORTUNITY FOR THE WORLD-WIDE PUBLIC TO PARTICIPATE IN AN
>INTERSTELLAR SPACE MISSION AND "COSMIC CALL"
>
>Encounter 2001, LLC (Houston) and Energia, Ltd. (Alexandria, VA, the
>American office of Rocket Space Corporation Energia) will announce an
>historic agreement to transmit a series of interstellar radio messages on
>behalf of the participants in the Encounter 2001 Millennial Voyage.
>
>
>----------
>
>Engergia is one of the most important aerospace firms in the world,
>responsible for the fourth stage of the Proton launch vehicle, Mir, and
>many of the international space station's Russian built components.
>
>However its U.S. subsidiary has done little visible work. (the deal where
>western satellites use Protons was negotiated directly between Lockheed and
>Energia along with Khrunichev, NASA deals directly with the Russian
>company, etc.) Involvement in this "Encounter 2001" deal does little to
>improve my impression of Energia. Yes, it's a catchy name. But does this
>'opportunity' offer anything beyond novelty?
>
>To me this entire concept seems silly. My voice has been transmitted to
>space literally thousands of times when I've used satellite links for phone
>calls (rarely now since most long distance is via fiber optic), news
>broadcasts, etc. The entire [astro] list, including this message is almost
>certainly retransmitted via satellite to some folks in distant regions
>which don't have more conveinent connections. As a rule the transmitters
>are very powerful and directional. Only a small percentage of any
>satellite transmission is actually intercepted by the satellite, the
>remainder continues towards interstellar space.
>
>It's interesting to extrapolate that since the vast majority of high power
>microwave radiation aimed towards space is aimed towards the geosync belt
>that certain portions of the sky are being radiated much more than others.
>(It is not a simple shape since most uplink sites are in the Northern
>hemisphere in higher technology areas, uplink sites and satellites are not
>located at regular intervals, the Earth's movement around the sun must also
>be taken in to account, etc.).
>
>In addition high power microwave terrestrial transmissions (also less
>common now due to fiber optics) also 'leak' most of their signal to space
>instead of reaching their intended destinations (the principle for many
>classified military radio listening satellites).
>
>For that matter every time I use my 5 watt handheld amateur transceiver my
>signal is transmitted to space, although with much less intensity. (enough
>to be heard clearly by an astronaut aboard Mir or the shuttle under the
>proper circumstances though). Under ordinary circumstances most R-F
>transmissions from VHF to light makes it to outerspace. So we've all had
>our messages transmitted to space. (and if any extra-terrestrial is
>reading this message and understands it then feel free to drop by for a cup
>of tea or raktajino.)
>
>Shortwave transmissions have been in existence since the beginning of the
>20th century and high power VHF transmissions (ones which are not reflected
>back to Earth by the ionosphere) have been in existence for the past five
>decades. While none of this has been directed towards any particular
>extraterrestrial viewer it's out there for whoever wants to intercept it.
>Somebody at a distance of 29 light years and is a "Star Trek" fan is
>probably fairly upset that the original series just got cancelled. But
>just has to hang in for about four years for the animated series and a
>couple of additional years until the movies. Granted there aren't many
>stars within 50 light years of the Earth which astronomers currently
>believe have terrestrial planets but with every year those signals go
>further out.
>
>(BTW did anybody notice in the film "Contact" that the Vegans took almost a
>decade before they decided to reply? Berlin Olympics 1936 + 52 years round
>trip light time makes 1988. The movie took place in 1997 - nine years
>later.)
>
>
>There are practical limits for the maximum distance a signal can be
>received before its so attenuated it's below the signal-to-noise floor.
>Here's a formula for calculating the range for detecting a signal. Radio
>astronomers, Electrical Engineers, and some ham radio operators should
>recognize the formula and values. (I believe I got this from the SETI
>League's web page)
>
>
>Range at which a signal can be detected
>
>R=8x10-6*(Pe*A/T)1/2*(t/B)1/4
>
> Notes:
> 1. R is in light-years
> 2. Pe is the effective radiated power of the transmitter in watts
> 3. A is the effective area of the receiving antenna in square meters
> 4. T is the excess receiver noise temperature in kelvin
> 5. t is the averaging time of the receiver in seconds
> 6. B is the bandwidth of the signal in Hertz
> 7. 8x10-6 is a constant and calculated using the formula:
1/(LY*(4*pi*K)1/2)
> 1. LY is a light-year in meters (9.4608x1015)
> 2. K is boltzman's constant (1.38x10-23)
>
>Note that this is the distance for detecting a signal - not decoding it.
>The odds of somebody in another solar system receiving any signal are _NOT_
>zero. Small yes. Zero no. I've heard that Arecibo could "communicate"
>with any similar size radio telescope in the Milky Way, although I don't
>have any reference or evidence to back up that statement.
>
>
>To me purposely transmitting messages as a commercial endeavor is about on
>the same order of 'pet rocks', sending your DNA in to space, 'imitation
>Titanic necklaces' and other similar frivilous novelties. The companies
>involved are not making any false or unsubstantiated claims about the
>chances for success or why they're doing it.
>
>However, this strongly reminds me of a con man who claimed that he had
>determined the frequency of heaven and was going to offer to transmit
>messages to God - for a fee of course. He noted that since his transmitter
>site was outside of the U.S. he didn't have to reveal the frequency to the
>FCC or other details of his operation. And that reminded me of when the
>magician and skeptic James Randi exposed a religious evangalist who claimed
>that he was receiving messages from God when he knew what his parishoners
>were telling his wife - and showed that they were using hidden radios.
>Randi commented that God apparently talked to the evangalist on (something)
>Mhz. - within the frequency band used by commercial VHF radios!
>
>
>Philip Chien, KC4YER
>Earth News
>world (in)famous writer, science fiction fan, ham radio operator,
>all-around nice guy, etc.
>
>
>