16 Jun 06
Originally posted by thechessguyCarl Sagan actually had a formula and it started with the conservative number of galaxies which is 400,000,000,000 (400 Billion galaxies).
This question was givin to my class at the end of the year.
What is the probability of there being life in the universe? Some people said that it would be very small and I agreed with the few people who said close to 100% who do you think would be right.
The formula progressed with Sagan's outstanding commentary (as usual) and finally arrived at the number 10.
I recall that Sagan started by using our galaxy, the Milky Way as an example and he stated that "if we assume we are the only form of life in our galaxy then calulate ... At this point he simply and elegantly whittled away using his knowledge of the COSMOS (what a great program) and finally arrived at the interesting number that we might expect life on 10 planets in the known 'billions and billions' of galaxies.
Mind you "galexies", not just stars but galaxies. Contemplating on this truely vast numer is both humbling and mind boggling.
I like to go to the NASA site and look at the photos of Hubble's deepest views of the universe - revealing a most beautiful and startling number of galexies as seen through Hubble's lens. For those unfamiliar with this, NASA focused Hubble on the "darkest, blackest' part of space in an attempt to 'see' what was out there. The results are nothing short of breathtaking, remarkable and thought-provoking.
Here is a link (not to NASAs which one should visit also) to a good look at Hubble deep field view.
http://hubblesite.org/newscenter/newsdesk/archive/releases/1996/01/
16 Jun 06
Originally posted by sword4damoclesCORRECTION...
Carl Sagan actually had a formula and it started with the conservative number of galaxies which is 400,000,000,000 (400 Billion galaxies).
The formula progressed with Sagan's outstanding commentary (as usual) and finally arrived at the number 10.
I recall that Sagan started by using our galaxy, the Milky Way as an example and he stated that "if ...[text shortened]... field view.
http://hubblesite.org/newscenter/newsdesk/archive/releases/1996/01/
I believe the final number was 1!
19 Jun 06
Originally posted by Sambo69I'm fully aware of the detail behind the drake equation including Frank Drake's development of it, but there are no clear ideas as to what numbers should go into any of the equations variables - so, effectively it's useless.
The Drake Equation was developed by Frank Drake in 1961 as a way to focus on the factors which determine how many intelligent, communicating civilizations there are in our galaxy.
Go to this site to experiment with different factors in the equation
http://www.activemind.com/Mysterious/Topics/SETI/drake_equation.html
20 Jun 06
1 edit
Originally posted by amannionHave you heard of the Green Bank conference where scientists from a wide range of fields discussed and agreed on a value for each factor in the Drake Equation ?
I'm fully aware of the detail behind the drake equation including Frank Drake's development of it, but there are no clear ideas as to what numbers should go into any of the equations variables - so, effectively it's useless.
The answer was that there are roughly 50 civilizations in the entire Galaxy which are likely to be engaged in trying to communicate using the means presently available to us on Earth.
http://www.daviddarling.info/encyclopedia/D/DrakeEq.html
20 Jun 06
Originally posted by Sambo69I think that amannion is correct.
Have you heard of the Green Bank conference where scientists from a wide range of fields discussed and agreed on a value for each factor in the Drake Equation ?
The answer was that there are roughly 50 civilizations in the entire Galaxy which are likely to be engaged in trying to communicate using the means presently available to us on Earth.
http://www.daviddarling.info/encyclopedia/D/DrakeEq.html
The Green Bank Conference may have met back in 1961 and agreed on arriving at the seven "best guess" factors, but it is also pointed out that the 'estimate' for only ONE factor out of those seven on the right side of the equasion could be estimated with any degree of confidence.
OK, here are the first two paragraphs from the page...after these follow the guessed of the other factors.
>>>Unfortunately, of the seven factors that appear on the right side of the Drake Equation, only one (R*) can be estimated at present with any degree of confidence. Current and near-future research on extrasolar planets will gradually reduce the uncertainties in three other factors, fp, ne, and fl. However, the values of the remaining three factors, which relate to the evolution of extraterrestrial intelligence and technology, are likely to remain a matter of pure speculation for a very long time, unless contact is made with a more advanced civilization which could convey this knowledge immediately.
Despite the enormous uncertainties involved in using the Drake Equation, which can result in a value of N from less than one to more than a billion, it is at least interesting and instructive to consider each of the factors involved. Aside from Factor 1, the values suggested below are simply the author's own "best guesses".
24 Jun 06
Discussion about certainty of life in the universe prompts a paraphrased quote by Douglas Adams, author of The Hitchhikers Guide to the..." and that is that us trying to fathom the vastnes and depths of space is a bit like a tea leaf knowing and understanding the history of tea production in China. Unlikely that we would ever know.
24 Jun 06
1 edit
Originally posted by Sambo69I've always wished that I came up with Drake's Equation. Talk about obvious! Then people would have to say my name everytime they talked about the probability of highly-intelligent life on other plantets.
The Drake Equation was developed by Frank Drake in 1961 as a way to focus on the factors which determine how many intelligent, communicating civilizations there are in our galaxy.
Go to this site to experiment with different factors in the equation
http://www.activemind.com/Mysterious/Topics/SETI/drake_equation.html
Edit: Surely though, in the original form, Drake didn't use the exact same variable on the left and right hand sides of his equation!
24 Jun 06
1 edit
The standard definition of life so far is an organism that exhibits :-
Organization
Metabolism
Growth
Adaptation
Response to stimuli
Reproduction
I've always wondered if this were a bit short-sighted. Shouldn't we
consider the other planetary complexities too?
Can life be given a mathematical equation instead and applied to
the age old eddies of dust storms and planetary weather systems?
What if for example Jupiters spot was actually a form of life?
edit -
'Animistic views of matter as alive
Two concepts can come under the heading of Animism. Firstly, one could believe that the distinction between life and unlife is illusory, which is to say that, to some degree, all matter is alive.
The Animist concept could also mean that life is a spiritual phenomenon, whereby a thing is made living by a non-physical principle of life. This view was also known as Vitalism.' - ref Wikipedia - 'life'