|MadSci Network: Astronomy|
The distances are huge between stars in the rim of a galaxy. I don't know the average figure, but I guess it's of the order of 10 light years. I have no idea what the distance might be between stars with habitable planets, but let's say it's of the order of 100 light years. Out here on the rim, it seems pretty unlikely that any civilization would ever be able to colonise anything but their own solar system. Distances are just too great - not to get from A to B but to maintain a single civilization with light-years between its scattered outposts. In the inner galaxy there must be few habitable planets - too many binary star systems, too many stars, too much radiation for life. Do you think any life form could really colonise the galaxy?
Re: Could aliens colonise anything?
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