Quote:
Originally Posted by eburacum45
All based in speculation, I know. But can I relate this to the observed sitation in our part of the galaxy?
<>
But that still leaves abiogenesis and lithopanspermia; I suspect they both may be fairly common, but this really is no more than a guess.
|
Personally, I don't think that lithospermia can be a common occurence, for transmitting life beyond a single stars envelope. Apparently, a rock travelling between star systems would require a minimum of several million years. However during this period the target star moves into and out of the region surrounding a star that could contain such rocks. So most rocks carrying would sit out in this region until passing star happened to capture the rock. If you calculate the volume of the capturing star sweeps, multipled by the number of such stars and divide the by volume of this region, you should end up with a very small probability of capture. Multiply this by the time of capture and you end up with life needing to remain viable on a rock for billions of years...
...and all without any possible preadaption for acceleration, immortality, re-entry or life in an alien environment.
Put some numbers into lithospermia theory and you end up with figures that make Drake equation scenarios seem very plausable by comparison.