From: Robert Powell <rpowell.nul>
Date: Mon, 10 Dec 2012 09:02:14 -0600
Archived: Mon, 10 Dec 2012 12:47:07 -0500
Subject: Re: Update To Our View Of The Drake Equation


>From: Ray Dickenson <r.dickenson.nul>
>To: UFO UpDates - Toronto <post.nul>
>Date: Mon, 10 Dec 2012 03:07:58 -0000
>Subject: Update To Our View Of The Drake Equation

>Hello List, another update to our view of the Drake Equation:

>At Last, How Many Alien Civilizations Are There?

>http://phys.org/news/2012-12-alien-civilizations.html

>[Quotation Begins]

>"Although the numerical results were not his objective, Maccone
>estimated with his SDE that our galaxy may harbor 4,590
>extraterrestrial civilizations. Assuming the same values for
>each term the Classical Drake Equation estimates only 3,500. So
>the SDE adds more than 1,000 civilizations to the previous
>estimate.

Although the Drake equation is fun to play with, this is a good
example of the old adage, "garbage in - garbage out."

>Another SDE advantage is to incorporate the standard variation
>concept, which shows how much variation exists from the average
>value. In this case the standard variation concept is pretty
>high: 11,195. In other words, besides human society, zero to
>15,785 advanced technological societies could exist in the Milky
>Way. If those galactic societies were equally spaced, they could
>be at an average distance of 28,845 light-years apart.

The author of the physics article contradicts himself in his use
of the Drake equation. On one hand he says that the latter terms
in the equation are so speculative that the values are
determined more by one's beliefs than by scientific evidence.
But then he turns right around and tries to draw some very
specific conclusions using the numbers that he "chooses" to put
into the equation.

The later terms are highly speculative, and the values one may
attribute to each of them might tell more about a person's
beliefs than about scientific facts.

Read more at:

http://phys.org/news/2012-12-alien-civilizations.html#jCp

The later terms are highly speculative, and the values one may
attribute to each of them might tell more about a person's
beliefs than about scientific facts.

Read more at:

http://phys.org/news/2012-12-alien-civilizations.html#jCp

>That's too far to have a dialogue with them, even through
>electromagnetic radiation traveling in the speed of light. So,
>even with such a potentially high number of advanced
>civilizations, interstellar communication would still be a major
>technological challenge. Still, according to SDE, the average
>distance we should expect to find any alien intelligent life
>form may be 2,670 light-years from Earth.

>There is a 75% chance we could find ET between 1,361 and 3,979
>light-years away. 500 light-years away, the chance of detecting
>any signal from an advanced civilization approaches zero. And
>that is exactly the range in which our present technology is
>searching for extraterrestrial radio signals.

>So, the "Great Silence" detected by our radio telescopes is not
>discouraging at all. Our signals just need to travel a little
>farther - at least 900 light years more - before they have a high
>chance of coming across an advanced alien civilization."

The argument about the "Great Silence" continues. There is
nothing in the article that convinces me otherwise.



Listen to 'Strange Days... Indeed' - The PodCast

At:

http://www.virtuallystrange.net/ufo/sdi/program/

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