tag:blogger.com,1999:blog-35651226341564828892012-02-16T03:19:54.417-08:00Alexanderhttp://www.blogger.com/profile/05557596039480786383noreply@blogger.comBlogger11100tag:blogger.com,1999:blog-3565122634156482889.post-51916750109871687492008-06-29T01:13:00.000-07:002008-06-29T07:23:59.517-07:00Let make only one numerical estimation:<br /><br />1) T1 = The oxygen, essential life component, in the Earth's<br />atmosphere exists and therefore emits O2 spectral line at least 200<br />million years = 200,000,000 x 365 x 24 = 1.75 x 10**12 hours<br />T2 = Total duration of all METI (Messaging to Extra-Terrestrial Intelligence, <a href="http://arxiv.org/abs/physics/0610031">http://arxiv.org/abs/physics/0610031</a>) transmissions from the Earth = 37 hours<br /><br />Thus, L = T1 / T2 = 4.7 x 10**10<br /><br />2) S1 = Solid angle of the O2 Earth's atmosphere radiation is all<br />celestial sphere, that is 4*Pi = 12.57 steradians<br />S2 = Solid angle of METI transmission from the Earth is (wavelength /<br />dish's diameter)**2 = 10**(-6) steradians<br /><br />Thus, M = S1 / S2 = 1.2 x 10**7,<br /><br />and N = L x M = 5.9 x 10**17.<br /><br />In other words, we can conclude that the probability to detect Earth's<br />O2 spectral emission by a hostile super-civilization is <span style="font-weight: bold;">N = L x M =</span><br /><span style="font-weight: bold;"> 5.9 x 10**17 (!!!!)</span> times higher than that of the METI transmissions.<br /><br />I hope, none of us have doubt about ability of hostile super-<br />civilization to detect remote planets and make spectroscopy of<br />atmosphere of these remote planets...<br /><br />Alexander.<div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/3565122634156482889-5191675010987168749?l=onenumericalestimation.blogspot.com' alt='' /></div>Alexanderhttp://www.blogger.com/profile/05557596039480786383noreply@blogger.com0