This article from the Daily Telegraph in the UK is interesting and has some interesting comments at the bottom. Particularly the first one about a new comet been ignored by the media - even though it passes between us and the sun.
This all has an impact on the Drake Equation since that was based on the assumptions that there were few if any 'earth-like' planets around locally. Now there seem to be more than you can shake a stick at!
Life of what species? Humans? We have to start thinking in wider terms.
The point I am making is that we dont KNOW what other species need to be able to live there. We cannot live in the (to us) freezing cold, but that does not stop other species living and colonising those areas.
Maybe you do not agree that on this forum we have shown areas of Earth which are too cold for humans to live comfortably, but there are obvious signs that someone is living there. This shows me, at least, that just because we assume somewhere is hostile, does not mean it is hostile for other species who have other requirements to survive.
Now... do you agree that the images of Antarctica, for example, show habitation beyond what humans currently develop there? (which appear to be prefabricated huts on stilts - see the thread on the Norwegian Troll station for links to images of the base)
If you do agree, then you must also agree that it is possible that other species can apear to survive quite comfortably in areas which we humans find hostile.
If you do not agree, then what do these images of Antarctica show?
If our galaxy is an example, then we should have almost 100% inhabited planets out there. These figures are way too low.
Every asteroid and every planet has probably been colonised by some being or other. Just like environments here on Earth, there are going to be environments out in space that are able to be inhabited by some being which has adapted to live there over the course of its evolution.
This Drakes equation is just a just an academic exercise and a waste of time and mental effort - in my opinion.
I've always felt that the Drake equation is flawed in that is doesn't go far enough we/the line of questioning:
Eg- Average time it takes for a surviving civilization to colonize extrasolar planets.
This is a realistic possibility given enough time+technological knowhow. Even if it takes many centuries to arrive at & colonize a single planet- the universe is old enough for this to have happened many many times over, & would therefore significantly effect the results .
& also factor in the number of galaxies in the known universe & the number would be effected even more.
& what about the fact that "life as we know it", w/our specific DNA structures,etc. Carbon-based life may be just one type of life in a vast spectrum of ways that nature can manifest life. Sinse the drake equation was first created (early 1960's) we've found out that 1)Life as we currently know it can thrive in extremely hostile environments 2)Life as we know it is just that 3)Life may take such an "alien" form to us that given sufficient evolutionary differences, we may not even recognize it as being alive. 4)Life can thrive on integration of substances that are extremely poisonous to us (lake in the US where bacteria inconporates arsenic into its DNA)
So basically I tend to think that the Ne number has to go up considerably.
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. The Drake Equation is:
N = N* fp ne fl fi fc fL
The equation can really be looked at as a number of questions:
N* represents the number of stars in the Milky Way Galaxy Question: How many stars are in the Milky Way Galaxy? Answer: Current estimates are 100 billion. fp is the fraction of stars that have planets around them Question: What percentage of stars have planetary systems? Answer: Current estimates range from 20% to 50%. ne is the number of planets per star that are capable of sustaining life Question: For each star that does have a planetary system, how many planets are capable of sustaining life? Answer: Current estimates range from 1 to 5. fl is the fraction of planets in ne where life evolves Question: On what percentage of the planets that are capable of sustaining life does life actually evolve? Answer: Current estimates range from 100% (where life can evolve it will) down to close to 0%. fi is the fraction of fl where intelligent life evolves Question: On the planets where life does evolve, what percentage evolves intelligent life? Answer: Estimates range from 100% (intelligence is such a survival advantage that it will certainly evolve) down to near 0%. fc is the fraction of fi that communicate Question: What percentage of intelligent races have the means and the desire to communicate? Answer: 10% to 20% fL is fraction of the planet's life during which the communicating civilizations live Question: For each civilization that does communicate, for what fraction of the planet's life does the civilization survive? Answer: This is the toughest of the questions. If we take Earth as an example, the expected lifetime of our Sun and the Earth is roughly 10 billion years. So far we've been communicating with radio waves for less than 100 years. How long will our civilization survive? Will we destroy ourselves in a few years like some predict or will we overcome our problems and survive for millennia? If we were destroyed tomorrow the answer to this question would be 1/100,000,000th. If we survive for 10,000 years the answer will be 1/1,000,000th.
The real value of the Drake Equation is not in the answer itself, but the questions that are prompted when attempting to come up with an answer.
I you plug these numbers into the equation
N* = the number of stars in the Milky Way Galaxy 100 billion Fp = Fraction of stars with planets around them 50% Ne = Number of planets per star ecologically able to sustain life 1 Fl = Fraction of those planets where life actually evolves 50% Fi = The fraction fo Fl that evolves intelligaint life 20% Fc = The fraction fo Fi that communicates 20% FL = The fraction of the planet's life during which the communicating civilizations survives 1/1,000,000th (10,000 years)
N = The Number of communicating civilizations in the galaxy = 200
The numbers that have been plugged into this equation are what "we" think is best true to the knowledge at hand.
So you end up with a 1000 alien species!!!
Of course this is just an equation, and it proves nothing other than the fact that be sheer numbers alone.......We are not alone.
On a side note....If you plug in the smallest numbers possible into this...even going against the "known" number of stars....and add a smaller value than what we "know" to be true.....You still end up with at least 3 alien communicating species.
Just food for thought.
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