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 around 200 billion.
fp is the fraction of stars that have planets around them
Question: What percentage of stars have planetary systems?
Answer: Thanks to advances in technology, new planets are being discovered every month. Within a few years we may have a reasonably accurate estimate. For now we'll say 20% (a standard estimate given my many including Frank Drake).
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: If you base it on our solar system you might say 3 planets could possibly support life - Venus, Earth, and Mars. There is also the chance that one or more of Jupiter's moons could support life. If our system is typical the answer may be between 3 and 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 guesses 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: Guesses 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: Who knows? Let's guess 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 another 10,000 years the answer will be 1/1,000,000th.
When all of these variables are multiplied together we come up with: N the number of communicating civilizations in the galaxy.
Man, compatible processing power to the SuperNES? And full colour too? Can you imagine? I'm sooooo hoping that SuperNES titles will be released for it....like, can you imagine Final Fantasy III for GameBoy? Or multiplayer GameBoy StarFox? Gnnnaaaaaahhhhhhh....
During his testimony Valenti played a brief clip from the MGM film "Stigmata." "This film was illegally downloaded this week and the film is still in many theaters in the U.S. and has not yet opened anywhere else in the world. But it is available on the Internet for free."
He 'illegally downloaded' the film? Arrest that man!!!
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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 around 200 billion.
fp is the fraction of stars that have planets around them
Question: What percentage of stars have planetary systems?
Answer: Thanks to advances in technology, new planets are being discovered every month. Within a few years we may have a reasonably accurate estimate. For now we'll say 20% (a standard estimate given my many including Frank Drake).
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: If you base it on our solar system you might say 3 planets could possibly support life - Venus, Earth, and Mars. There is also the chance that one or more of Jupiter's moons could support life. If our system is typical the answer may be between 3 and 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 guesses 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: Guesses 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: Who knows? Let's guess 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 another 10,000 years the answer will be 1/1,000,000th.
When all of these variables are multiplied together we come up with:
N the number of communicating civilizations in the galaxy.
Man, compatible processing power to the SuperNES? And full colour too? Can you imagine? I'm sooooo hoping that SuperNES titles will be released for it....like, can you imagine Final Fantasy III for GameBoy? Or multiplayer GameBoy StarFox? Gnnnaaaaaahhhhhhh....
Repeat story....we've already seen it, i believe the story was last titled something about matchbox size computers.
During his testimony Valenti played a brief clip from the MGM film "Stigmata." "This film was illegally downloaded this week and the film is still in many theaters in the U.S. and has not yet opened anywhere else in the world. But it is available on the Internet for free."
He 'illegally downloaded' the film? Arrest that man!!!
Has anyone had any luck in updating Corel Linux with KDE 2.0?