Posted on 07/23/2004 9:15:08 PM PDT by ckilmer
EXO WORLDS
First Contact Within 20 Years: Shostak
Will the 20s see ET roar onto center stage Mountain View CA (SPX) Jul 22, 2004 If Intelligent life exists elsewhere in our galaxy, advances in computer processing power and radio telescope technology will ensure we detect their transmissions within two decades. That's the bold prediction from a leading light at the Search for Extraterrestrial Intelligence Institute in Mountain View, California. Seth Shostak, the SETI Institute's senior astronomer, based his prediction on accepted assumptions about the likelihood of alien civilisations existing, combined with projected increases in computing power.
Shostak, whose calculations will be published in a forthcoming edition of the space science journal Acta Astronautica, first estimated the number of alien civilisations in our galaxy that might currently be broadcasting radio signals.
For this he used a formula created in 1961 by astronomer Frank Drake which factors in aspects such the number of stars with planets, how many of those planets might be expected to have life, and so on. Shostak came up with an estimate of between 10,000 and 1 million radio transmitters in the galaxy.
To find them will involve observing and inspecting radio emissions from most of the galaxy's 100 billion stars. The time necessary for this formidable task can be estimated from the capabilities of planned radio telescopes- such as SETI's 1-hectare Allen Telescope Array and the internationally run Square Kilometre Array- and expected increases in the power of the microchips that sift through radio signals from space.
Shostak assumed that computer processing power will continue to double every 18 months until 2015- as it has done for the past 40 years. From then on, he assumes a more conservative doubling time of 36 months as transistors get too small to scale down as easily as they have till now.
Within a generation, radio emissions from enough stars will be observed and analysed to find the first alien civilisation, Shostak estimates. But because they will probably be between 200 and 1000 light years away, sending a radio message back will take centuries.
Paul Shuch, executive director of the SETI League, a separate organisation in New Jersey, says Shostak's prediction ignores one important factor. "It is altogether reasonable to project the development of human technology, based upon past trends and planned investments," he says.
"But predicting the date, the decade or even the century of contact is another matter because the 'other end' of the communications link is completely out of our hands. It would be nice to think we know something about the existence, distribution, technology and motivation of our potential communications partners in space, but in fact, we don't."
Shostak admits that there are myriad uncertainties surrounding his prediction, but he defends the basis on which he made it. "I have made this prediction using the assumptions adopted by the SETI research community itself."
We don't *know* that Gravity travels at C. We know that Light travels at C. We've measured it. We've observed it. We've tested it.
Not so with Gravity.
What we've *observed* is that the orbit of our planets around our Sun can only be accurately calculated if Gravity is presumed to be nearly infinite in speed.
Our orbits *appear* to show infinitely fast Gravity.
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142 - "Our orbits *appear* to show infinitely fast Gravity."
Does gravity - 'travel'? It seems more like gravity 'is'. I agree, if it travels, it most likely 'is' there before 'light' gets there.
Now, what about magnetism? How 'fast' are 'magnetic' waves or lines of force?
That's obvious. For our purposes, however, it doesn't matter.
Whether Gravity propagates at near infinite speed (Newton), or whether Gravity forms an instantaneous Geometry (Einstein), the end result is that information can be transfered using Gravity faster than Light...because it doesn't matter if you are opening and closing a geometric channel, or modulating a Gravity wave. Either method will enable two vastly distant observers to communicate with each other.
Modifying a geometry and modulating a wave both convey information, after all.
I'll leave it for you to decide, therefore, whether an advanced civilization would use Gravity or radio waves to communicate across vast distances.
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Could you guys deal with this ignoramus? I am tired of playing with him.
I had hoped my links would have helped. FYI, Southack is getting his ideas from Tom Van Flandern.
Actually, we are not looking for patterns at all. Just finding a narrowband carrier is enough. :-) The problem is just how big this universe is. It takes light (radio waves) years just to reach the nearest star. The other rub is where and what frequency do we look at? It is not unlike finding a station on your car radio if there was only one radio station out there, you don't know the frequency, you only had a directional antenna, and the radio station could only broadcast so far in any direction.
Imagine firing a super-range cannon. The cannonball doesn't travel in a perfectly straight line tangential to the Earth; instead, it "hugs" the curve of the Earth... e.g., if you fire it 6 feet above ground, the cannonball stays 6 feet above ground instead of travelling in a line tangent to the Earth.
Fire it hard enough, and it'll go around the Earth completely before falling down. Fire it even harder, and you'll have a satellite that'll stay up a really long time before it gradually gets lower & slower until it finally crashes into the ground.
It's the exact same way with the planets, they're giant cannonball that are revolving around the Sun, and indeed, they're slowly losing energy and "falling" into the Sun. Hope that helps a bit.
Gee, Boris, I never realized how rude and condescending you were. You call him names, why? Because he shares a similar interest, but a dissimilar view. I enjoyed Southhacks rambling much more than your technical obfuscation. Anger in technical argument often demonstrates weakness of position.
Ask Physicist or RadioAstronomer if my responses were "technical obfuscation" or perhaps concise descriptions of why modern physics disdains his 19-th century notions.
If you find them "obfuscation" I suggest you should read up on physics yourself.
--Boris
Just trying to help. You wanna be a jerk, jerk away.
Instantaneous, action-at-a-distance, and never disproven placemarker.
No, he's not getting his ideas from Van Flandern. He has pulled a quote once from Flandern's web site, but that's hardly germaine.
The character assasination attempts on this thread are going beyond the pale.
You of all people, who uses an *infinite* speed of Gravity to calculate planetary orbits (no other method is accurate), should be careful about criticizing someone like me who has pointed out that it just *might* be possible that Gravity is faster than Light.
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Truly a classic. He proposes a "proof" that gravity propagates at the "speed" of "c2" at #84 of that thread, in which he appears to be cognizant of, but not bothered very much by, the fact that the units of "c2" aren't even a velocity.
As they used to say in freshmen physics; "quantity calculus" is your friend.
;-)
Interesting concept at #134. Thanks for posting that.
Oh goodness, how could something propagate at a rate that isn't a fixed velocity?! < /SARCASM >
Methinks someone has forgotten a term known as: acceleration.
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Excuse me! I have not character assasinated anyone. Go read that other thread Physicist linked to, my links I posted to you, and do some google's of refutations of Van Flandern. I think you will then see where you have made your error.
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