What do you think about the Drake equation?

Question

It says that the number of extraterrestrial civilizations trying to contact us right now can be predicted by a simple equation:
N=RPNLCT where...
N is the number of civilizations
R is the number of stars formed in the galaxy each year
P is the probability that a star will have planets
N is the probability that an Earth-type planet, capable of
supporting life, is among them
L is the probability that life will actually develop on that planet
C is the probability that life will lead to a technological
civilization capable of sending radio signals into space
T is the lentgh of time for which those signals will continue to
be sent

Answer 1

I'm surprised that none of the respondents have not sourced Amir Aczel's book Probability One? Aczel has pointed out that science now says that 75% of all known solar systems are binary in nature. This means two suns per solar system, thus making the chance of life greater than Drake's conservative equation! Drake based his hypothesis on single star systems in 1960. According to Aczel's hypothesis this increases the chances of life and intelligent life to double in probability! I would also like to point out that Drake, Carl Sagan and John C. Lilly ( Lilly was asked to take part based on his research with dolphins and sensory deprivation expertise) took part in a program to establish extraterrestrial contact under Project Ozma. This project was located in West Virginia at the Green Bank radioastronomy observatory, established in the early 1960's. Interestingly, when the observatory was operating for the first time the Ozma personel received a signal form Tau Ceti. According to Drake they were absolutely stunned with the signal, and by all accounts the program went "black" and a disinformation campaign was put into place to discredit the signal. Drake's explanation was that the signal could not be located after a second on-line try. I would also like to mention that the "Big Ear" facility located in Columbus, Ohio also received a signal known as the "Wow" signal sometime in the 1980's.

There are many presuppostions that an advance civilization has not contacted us and that the chance of finding life and receiving a signal are so remote that it will never happen. I disagree with this anthropocentric analysis because we are assuming that information is free under the National Security State and that our terrestrial technology and "their" technology are compatible with how we decipher a signal. What about Scalar technology as an example? Even if a civilization millions of years old used radio waves as a form of communication, how do you really know we haven't picked up a signal? You don't because contrary to popular belief information is not free and most people in the science community do not have a top secret security clearence, nor do they have a "cosmic" security clearence. Academicians do not like to hear this because most feel that they are in on cutting edge technology. Think again! This is why we have "Black" and "Grey" programs that are so compartmentalized that one would need a Special Access Program based on "a need to Know" in order to be fully apprised of a project. Radioastronomy would definitely fall under such programs!

Answer 2

It relies upon on what you recommend by existence sort like. in case you elect an precise, reliable prediction--no. yet then, Drake in no way claimed it became. What Drake did became practice a thank you to pass approximately making an ecucated guess (no longer aprediction) approximately how basic liveable planets or alien civilizations must be. the belief is rather basic: the equation is basically a itemizing of all of the climate scientists thought have been significant (stellar radiation, planetary length, and so forth.)--alongside with the final estimates of what the possibility of each became. That became many years in the past-an as much as the instant version might have most of the values replaced, or perhaps some diverse variables. And--as you're saying, we've not got any reliable figures for some--regardless of the undeniable fact that we do have plenty extra perfect figures now for others. this is incredibly basically an prepared way tothink approximately this subject remember. And from that point of view, definite, an fairly existence like one-as long as you keep in mind it incredibly is all it incredibly is.

Answer 3

Karl asserts life only originated once on the earth. Actually, it may have arisen several times. We cannot tell if previous incarnations of unicellular life simply went extinct by eukaryotic displacement. Also, the genetic difference between the archaea and bacteria is greater than the difference between archaea and eukaryotes. We may already have examples of multiple independently originated life forms here on earth.

In 1990 we did not know of any planets beyond our solar system. Today we know of more than 200, and we thus are getting excellent estimates for P. NASA cancelled the Terrestrial Planet Finder project, but there are other missions launching soon that will give us a very good handle on N.

C & T will remain a big unknown for a long time to come, even if we establish contact with another civilization. Only after we have explored a good fraction of our galaxy will we have a sufficient sample size to estimate values for these. We may launch the first interstellar spacecraft some time later this century, if we don't squander all our resources on unprovoked war. These ships will be slow, and it will be thousands of years before we get signals back from them from neighboring stars. We won't really have a decent handle on C or T for another 50 thousand years, and then only if L is very large.

Many biologists think L is almost inevitable, giving sufficient conditions. Life on earth arose very early in our history, more than three billion years ago (and the first 1.5 billion years of our 4.5 billion year history was especially unpleasant). But for the present time we lack hard evidence L > 1 in 100 billion. (There are 200 billion stars in our galaxy, but it is possible ours is the only galaxy out of the 100 billion in our universe that harbors life).

If we ever launch a TPF, it will be able to resolve surface features of earth sized exoplanets. With that we would be able to detect the presence of free oxygen in alien atmospheres--a key indicator of photosynthetic organisms. Without L, of course, C & T cannot exceed zero.

Answer 4

It's a way of estimating that number, and thinking about the question of extraterrestrial civilizations. As such, it's an important teaching aid. Advances in astronomy and biology are leading to more accurate values for some of the terms, but others are just wild guesses.

Answer 5

I was first introduced to this concept in a television show called COSMOS. I believe it to still be available and occasionally I find it on the science chanel. The problem with this SIMPLE EQUATION is our lack of precise data. It is kind of like some linear algebra matrix manipulations that result in so many calculations that the precision of the answer is less than one significant digit. Depending on the values plugged in there is either practically no chance of our ever meeting another inteligence or that there ought to be one in every other planetary system.

Answer 6

as long as the L = something like infinity to one odds, i am okay with it.
consider that life has had an almost infinite number of chances to develop on earth, at least one chance per milliliter of water multiplied by every second that has passed since the earth cooled and it only happened once here. even the most ideal lab setting cannot reproduce it.
even if every planet were very earth like odds are it would never happen in a billion billion universes.
after all the earth is pretty earth like, and it (virtually) never happens here.

Answer 7

The equation's as valid as it ever was. Since most of the factors are still completely unknown, it continues to tell us, fundamentally, nothing.

It does give us an idea of the work that remains to be done in strophysics. Science is a long way from finished!

Answer 8

I think it is useless. It is a bunch of things, most of which we don't know, combines to tell us something else we don't know. In particular, L and C are just a wild guesses. It does not add knowledge at all.

Answer 9

is an interesting aproach but is quite impossible to prove, so is kind of pointless, and is not like im smarter than mr drake... but come on!

Answer 10

i still say eye witnesses are better
http://www.youtube.com/watch?v=PBtVOhAl2ks
http://www.youtube.com/watch?v=MmgncYEuIXk