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The Drake Equation assumed there were only numbers, as in number of stars with planets, to be considered when equating the odds of live arising on a planet or planets. The missuse of statistics was what I tried to refer to.

Dr. Ross appears to have started with a survey of what must be the conditions and for how long in order that life arise and advance to the stage of intelligently surveying the universe around the planet upon which that intelligence arose. From one perspective, it is sort of like the Drake Equation was conceived for a box of "S" size, while ignoring that the "S" size was not constant. That box size dramatically effects the fundamental conditions required for a 'long enough quiet period' so that life evolves to the level of intelligence. Hey, the whole notion of intelligent life taking more than 500 million years to emerge may even be erroneous. It took that long on this planet, but can we apply the process fundamentals to other planets? We assume we can, for contemplation purposes. Given a consistency of temporal conditions (time is neither expanding or contracting), the changes to the universe, the environment, the biochemical processes, all these other variables were mostly ignored in the Drake Equation.

I have read a lot of stuff like what Ross puts out. For one thing Ross does not even know what life is. How it got started. What makes it tick.

What Ross doesn’t consider is that Life is a part of the very fabric of the Universe. That Life is a natural and normal occurance.

For someone to make assumptions as he does about something he doesn’t even comprehend is pretty silly don’t you think??

John

http://www.guardian.co.uk/science/2008/feb/18/extrasolar.planets?gusrc=rss&feed=science

The Drake Equation assumed there were only numbers, as in number of stars with planets, to be considered when equating the odds of live arising on a planet or planets. The missuse of statistics was what I tried to refer to.

The Drake Equation didn't assume there were only numbers -- it was an attempt to estimate the number of civilizations in the galaxy. Since we can't go beyond our own Solar System, that's the best we've got. Making assumptions is something *everyone* (including Ross) will have to do. Meanwhile, the estimate varies based on new information, new findings, new assumptions, etc.

This equation consists of 8 variables, all of which are explained below.

N is the number of civilizations within our galaxy that are capable (technology-wise) of communicating with us.

R* is the average rate of star formation in our galaxy. This value is currently thought to be approximately 20 stars per year.

fp is the fraction of these stars that have planetary systems. The fraction of stars with planets in our galaxy is one of the unknown factors in Drake's Equation. The Hubble Space Telescope has spotted multiple “protoplanetary disks" (orbiting debris of gas and dust around a star out of which planets are thought to be formed) around stars. Astronomers have also discovered massive planets resembling Jupiter orbiting stars. These observations indicate that planetary systems could be common throughout the galaxy.

ne is the number of planets that have environments suitable to the development of life in each system. In other words, how many earth-like planets are there? Planets that are in the habitable zone^? of a star are able to maintain a temperature that would allow liquid water, and life as we know it needs liquid water to develop and survive.

fl is the fraction of these planets that actually have life. Just because a planet is in the habitable zone of a star doesn't mean that planet will have life. Other factors such as an abundance of certain chemicals and a continual source of energy are necessary for life to develop.

fi is the fraction of these planets that have intelligent life. Intelligence could just be a fluke. Biologist Ernst Mayr noted that “It took intelligence millions of years to evolve on Earth, and it only involved once out of a billion species of earthly animals”. Intelligent life on other planets in the galaxy is likely to be as rare.

fc is the fraction of the species of intelligent life that have developed technology for interstellar communication. Consider the hundreds of thousands of species on Earth. Only we, the human race, have developed any form of technology. Also, just because an intelligent species is capable of interstellar communication, who knows whether they'd have the desire or ambition to initiate such communication?

L is the average lifetime of a technological civilization, or the length of time civilizations release detectable signals into space. This is one of the most difficult factors of the Drake equation to estimate. When species have developed technology capable of sending messages out into space, they most likely also have the technology to (inadvertently) destroy themselves.

Obviously fp has a much higher value than previously thought, since for a time binary stars were considered more common. ne is one that can be refined as orbital telescopes, larger scopes, and new techniques proliferate. L was one used by the likes of Carl Sagan to grind various political axes, and -- like at least a few others -- are entirely based on assumptions of various kinds. There won't be any widely acceptable data on any of these until at least one unequivocal contact with extraterrestrial civilization is made, probably via the electromagnetic spectrum.

N	is the number of civilizations within our galaxy that are capable (technology-wise) of communicating with us.

R*	is the average rate of star formation in our galaxy. This value is currently thought to be approximately 20 stars per year.

fp	is the fraction of these stars that have planetary systems. The fraction of stars with planets in our galaxy is one of the unknown factors in Drake's Equation. The Hubble Space Telescope has spotted multiple “protoplanetary disks" (orbiting debris of gas and dust around a star out of which planets are thought to be formed) around stars. Astronomers have also discovered massive planets resembling Jupiter orbiting stars. These observations indicate that planetary systems could be common throughout the galaxy.

ne	is the number of planets that have environments suitable to the development of life in each system. In other words, how many earth-like planets are there? Planets that are in the habitable zone^? of a star are able to maintain a temperature that would allow liquid water, and life as we know it needs liquid water to develop and survive.

fl	is the fraction of these planets that actually have life. Just because a planet is in the habitable zone of a star doesn't mean that planet will have life. Other factors such as an abundance of certain chemicals and a continual source of energy are necessary for life to develop.

fi	is the fraction of these planets that have intelligent life. Intelligence could just be a fluke. Biologist Ernst Mayr noted that “It took intelligence millions of years to evolve on Earth, and it only involved once out of a billion species of earthly animals”. Intelligent life on other planets in the galaxy is likely to be as rare.

fc	is the fraction of the species of intelligent life that have developed technology for interstellar communication. Consider the hundreds of thousands of species on Earth. Only we, the human race, have developed any form of technology. Also, just because an intelligent species is capable of interstellar communication, who knows whether they'd have the desire or ambition to initiate such communication?

L	is the average lifetime of a technological civilization, or the length of time civilizations release detectable signals into space. This is one of the most difficult factors of the Drake equation to estimate. When species have developed technology capable of sending messages out into space, they most likely also have the technology to (inadvertently) destroy themselves.