The alien hypothesis?

[jbor at bigpond.com]

Thanks. Science is way cool!

best

On 15/10/2005, at 12:16 AM, Blake Stacey wrote:

> Quoting jbor at bigpond.com:
>
>> Actually, "Science" does seem to spend an awful lot of time (and 
>> money)  investigating whether Mars could support, or has supported, 
>> organic  life and so forth. I'd imagine that the probability of the 
>> existence of  "life" elsewhere in the universe could be calculated 
>> scientiffically,  i.e. via some sort of equation where the expanse of 
>> the known universe  is moderated against the likelihood of 
>> environmental and chemical  conditions needed to generate and sustain 
>> "life" manifesting  spontaneously. I suspect that the odds would be 
>> quite good.  Hypothetically-speaking, that is.
>>
>
> Been done.  We have the "Drake Equation", named not for any Celtic 
> dragon but
> for astronomer Frank Drake, which takes the big question "Is there 
> anybody out
> there?" and divides up our uncertainty.  Each factor in the Drake 
> Equation can
> be estimated (or guesstimated) based on a different set of scientific 
> findings.
> The first number, R*, is the rate of star formation in the galaxy, 
> which we can
> figure out by looking through telescopes.  Other parameters, like f_L 
> -- the
> fraction of possibly life-bearing planets which in fact go on to 
> develop life
> -- must be estimated using biochemistry, molecular biology and 
> geology.  While
> all of these variables have considerable "plus or minus" as regards 
> their
> values, the most contentious is probably the last, the number Drake 
> called L. The variable L represents the average lifetime a 
> civilization stays "alive". Drake estimated L at 10 years; Michael 
> Shermer puts it at 420.  (Pass the bong,
> dude.)
>
> http://en.wikipedia.org/wiki/Drake_equation
>
> http://en.wikipedia.org/wiki/420_(drug_culture)
>
> In Timothy Ferris's book **The Mind's Sky**, he quotes a poem which 
> apparently
> floated through the SETI community:
>
>> Of all the sad tales
>> That SETI might tell
>> The saddest would be
>> A small value for L.
>
> Freeman Dyson pointed out, some years ago, that the Drake Equation 
> should really
> be called the "Drake Inequality".  According to Dyson, the equation 
> needs one
> more factor, a parameter to represent how many "daughter" 
> civilizations are
> colonized by each intelligent species.  The Drake Equation as it was 
> originally
> stated gives the **minimum** number of civilizations in the galaxy, 
> but if
> civilizations achieve interstellar spaceflight, the actual number 
> would be
> higher, possibly much higer.  At present, the only way to estimate 
> this number
> is to take an average over the values proposed in science-fiction 
> novels.
>
>> As to "intelligent life" or UFOs, well, that'd be a separate 
>> equation.  Or a derivative of the first. But the concept of 
>> "intelligent life" is  problematic in that it's another one of those 
>> self-defining systems or  semantic constructs. And, coming at it from 
>> another perspective, it's a  little but egotistical, if not downright 
>> solipsistic, to assume for  oneself the mantle of supreme being in 
>> all of existence.
>>
>
> Don't wanna go there.  Murky waters.  Let me just say that the SETI 
> people have
> worked very hard to imagine what sort of communication might be 
> possible with
> species as different from humanity as scientists can imagine.  (As 
> different,
> that is, while still being consistent with known physical law.  Beings 
> from the
> Q Continuum need not apply.)
>
> Blake
>
>