Discovery of many extra solar planets with some of them having conditions favourable to harbour life have raised hopes for earth alike biological destinies and evolutionary consequences elsewhere in the universe. This paper is an attempt to hypothesize the earth a like evolution and biological destiny for emergence of Extra-Terrestrial Life (ETL) and Extra-Terrestrial Intelligence (ETI) on an exoplanet. Extraterrestrial life could be unimaginably different in its form, shape, composition, dimension, functionality, evolution and even in biochemistry from the life that evolved on earth and might be inconceivable to us. Therefore, some innovative ways and means of detection of extraterrestrial life are also being discussed, so as to keep the possibilities of detection alive. Furthermore, an attempt has been made to modify the Drake equation for quantifying our ne science about the number of earth approaching intelligent alien civilizations of our milky way and fractions fh, fg , fv, ft have been included in this equation for this purpose. The fraction fh denotes the alien civilizations which develop technologies to detect habitable zones in the galaxy, the fraction fg of such alien civilizations which develop intragalatic travel technologies, the fraction fv of those alien civilizations which start their voyage towards our solar system and the fraction ft of earth approaching alien civilizations who wish not to hide them in the earth's environment or in our near and or far space and who's technological or physical presence is conceivable to us through our sensory range and or technology spectrum. The factor T stands for the average travel time for such intelligent aliens to reach earth.
However, as of now there is no scientific evidence of extraterrestrial life. Further, the search for extraterrestrial life is constrained by our limited observations in the infinite cosmic sea with vast distances and limitations of the present day technologies.
Published Date: 2022-08-18; Received Date: 2022-07-18