lists many North American cities and times when the ISS can be viewed. If you have never before seen the ISS pass over, it is quite a sight. It moves very quickly and is incredible to imagine that there are people actually up there.
I'll beable to see it tonight in about 30 minutes. Check it out.
Try reading this and maybe it will spark some debate:
What are the possibilities that we will find ET signals? To address this issue, astronomer Frank Drake introduced an equation to calculate the number of ET civilizations in the galaxy in 1961. The equation, now referred to as the Drake Equation, considers astronomical, biological and sociological factors in its estimates:
N = R * x f p x n e x f l x f i x f c x L
where:
• N - Number of communicative civilizations
• R* - Average rate of formation of stars over the lifetime of the galaxy (10 to 40 per year)
• fp - Fraction of those stars with planets (0 < fp <1, estimated at 0.5 or 50 percent)
• ne - Average number of earth-type planets per planetary system (0 < ne <1, estimated at 0.5 or 50 percent)
• fl - Fraction of those planets where life develops (0 < fl <1, estimated at 1 or 100 percent)
• fi - Fraction of life that develops intelligence (0 < fi <1, estimated at 0.1 or 10 percent)
• fc - Fraction of planets where intelligent life develops technology such as radio (0 < fc <1, estimated at 0.1or 10 percent)
• L - Lifetime of the communicative civilization in years (estimates are highly variable, from hundreds to thousands of years, approximately 500 years for example purposes)
Note
Some forms of the Drake equation add an additional term after R* -- fs, for the fraction of stars formed that are sun-like stars. Non-zero values of fs vary between zero and 1, but are estimated at 0.1 or 10 percent.
The fractions in the Drake equation have non-zero values between zero and 1. The first three terms on the right side of the equation are the astronomical terms. The next two are the biological terms. The final two are the sociological terms.
The Drake equation has been a guideline in SETI research. The value of N has been calculated to be anywhere from thousands to billions of civilizations in the galaxy, depending upon estimates for the other values.
If we use the estimates listed above, and decide R* equals 40 , then the drake equation becomes:
N = (40 stars per year) x (0.5) x (0.5) x (1) x (0.1) x (0.1) x (500 years) = 50 civilizations
As you can see, the results of the Drake equation are highly dependent upon the values that you use, and values of N have been calculated at anywhere from 1 to in the thousands. Some aspects of SETI and general astronomical research have been devoted to gathering data for reliable estimates of the terms in the Drake equation, such as the number of extrasolar planets. See the Links section for more details on the Drake Equation.
mabye if you posted it earlier I would have gone out and watched it, instead of half an hour before it happens. Also, I never knew there was an equation to estimate the number of Alien civilizations that we may be able to talk to