Quote:
|
Originally Posted by Beery
Quote:
|
Originally Posted by rogerbo
Who are we that we should be the only ones in the Universe ??
It may bee that there are no UFO's realy seen on this Planet, but the whole Univers is soooooo Big and in many parts Older the the Earth itself and if the Theory that life came to earth by comets and meteors is right the to asume that Humans are the only inteligent Race in the Univers is just ignorant.
|
I agree, but that in no way argues for the existence of aliens who have visited Earth.
The fact is, the distance between us and our nearest interstellar neighbour is HUGE. A spacecraft travelling at the highest speeds we've been able to achieve in space would take over 50,000 years to reach Alpha Centauri. While I'm pretty sure aliens exist, the big question is whether they can get off their planet before the civilization is destroyed by an asteroid impact or other natural catastrophe. If they can, the odds are that they won't be able to get settled on a planet outside their solar system because the chances of finding a suitable planet and being able to reach it are very small indeed. The other thing is that any civilizations in the universe will tend to inhabit areas far away from a galactic hub, because when you place stars closer together it becomes less and less likely for any civilization to last long before some catastrophe destroys it. So the civilizations that may exist probably exist quite far from their neighbouring stars. |
IIRC the majority of star systems in this Galaxy are Binary system or bigger (Our good neighbors in the southern sky Alpha Centauri is a Triple Star System) so if advanced space faring life took root there its possible that even an extinction level event on their homeworld wouldn’t wipe them out since there is possibly a large number of planets and moons within their home system. Planets have been discovered within Trinary systems ('HD188753 Ab' the "Tatooine Planet" 149 light-years away in the constellation Cygnus for example). Even a “Distant” Star system out here in the Orion Arm is quite close Alpha Centauri is 4.25 ly, the closest planet yet discovered is 10.4 ly in Epsilon Eridani, HD 128311 54 ly away in the constellation Boötes has at least two planets b is about 1 AU from its star and c is 1.76 AU (sound familiar, Earth is 1 AU from Sol and Mars is 1.52 AU). If we could build a spacecraft that traveled at only 1/3rd of the Speed of Light it would take only 12 years to arrive at Alpha Centauri, there is a lot of systems in our reach. We went from LEO to the Moon in 20 years, "high" speeds like this aren't very far off if the world applied it's self.