(08-24-2023, 07:37 PM)Sneakers Wrote:

(08-24-2023, 12:17 PM)mikesez Wrote: Their motives, intentions, and physical form are all irrelevant to my point.
My point is it is very very hard to get off of our planet, and any species that has mastered interstellar travel will likely come from a planet that is much much easier to launch large amounts of mass and energy off of.  At that point such species will be looking for places that are like their planet or better.  Not worse.  We might observe such a species trying to mine asteroids and comets in our solar system and convert them into colonies.  All the resources they would ever need are on those asteroids.  Maybe after a long period of exploiting our asteroids they might decide to give planetary colonization a try, but we would observe their asteroid activities first.

I would say "Quit while you're ahead" but that ship sailed with your first post.

So, the motives of these theoretical visitors coming to Earth are admittedly unknown to you, yet you still know what type of planet they're looking for?  That's amazing, how do you do it?  I could only assume their planet was one giant desert, and they wanted to live at the beach.  Or maybe it was just a bunch of teenage aliens out for an interstellar joyride in a stolen spaceship.  

P.S.  What resources does an alien lifeform (of unknown physical characteristics) require?  I couldn't find the info anywhere online.  Is there plenty of water on those asteroids?  I've heard they like swimming pools.

You're thinking in terms of the conditions necessary for life as we know it to evolve.  For that you need liquid water and for liquid water you need an atmosphere and for an atmosphere you need a lot of planetary mass, etc.

But those aren't the conditions necessary for interstellar dispersal.  If the species is capable of building space capsules that contain the artificial atmosphere it needs for its life cycle, and able to accelerate those capsules across interstellar space, it will also be able to mine asteroids for the raw materials needed to create more capsules.  To answer your question, yes, most comets have ice and many asteroids are made up of mineral hydrates.  If you're close enough to a star and you have solar panels, you can mine asteroids for basically the entire periodic table of the elements, certainly the first couple of rows.  So the material for those capsules will be collected beyond the gravity well and the capsules will remain beyond the gravity well.  The capsules will spin to create their own gravity if the species needs gravity for any reason.

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