wood
wooden furniture would be quite the novelity to someone who has never seen it.
That would assume that thier bodies had any use whatsoever for the shape we use for furniture.
All of you are on to something. Whoever said, “Slave Labor,” probably has the most right idea. But, people on our planet pay alot of money for entertainment. And, what could be more entertaining than to see a bunch of off-worlders do wierd things that only off-worlders do. So whoever mentioned themes along the lines of “Cultural Diversity,” probably has a good thing going. All of the popular movie themes to-date are viariants of these two ideas. There are no naturally occurring materials on Earth that cannot be found easier elsewhere in space, but the labor required to process these commodities can only be found on life-supporting planets like the Earth. Then the entertainment value of watching Earthlings suffer, triumph, and manipulate each other for power wealth and glory, (especially glory) would amuse other races just like it amuses us.
As far as I know, Earth is the only place in the solar system which contains cellular phones that can send text messages and movie clips.
Even if they are aquatic beings with no use for furniture as we make it whatsoever, wood is still an interesting material to a species from a planet with no trees. After all, it’s rigid without needing a calcium or silicon matrix (as in coral or rocks).
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[sup]The Hula Hoop[/sup][/ul]
I’m sorry, but I don’t get the slavery thing…
assuming that the aliens have automatic control systems on their ship, they would almost certainly have the ability to produce robotic mining equipment
- for mining asteroids, robots would be far superior to humans
if the aliens wanted to mine the Earth for these concentrated igneous minerals, they would be better off using their own robots than humans- who get tired, eat and drink and excrete, and are really only useful as control systems for big dumb machines anyway.
I am assuming that the aliens use artificial intelligence, which is very likely to be developed in the same timescale as interstellar travel.
Some species of aliens would never develop electronic intelligence, perhaps- these species would probably use biological intelligence to control and monitor their systems.
- if this biological intelligence has been modified to control complicated systems, perhaps by genetic engineering, it will be intrinsically better at performing the tasks that humans might be enslaved to do- say mining gold , uranium or molybdenum using heavy machinery.
You see, I think it is absurd that the Daleks, or the Cardassians, or the Thrints would come to this planet to make the population work in mines with pick-axes;
if they have got this far, hey probably don’t need manual labour.
Now enslaving the Earth’s population to produce cultural artifacts, that I can imagine… we might be required to produce scrimshaw, hand made wooden furniture, hula hoops, soap operas, anime, Michael Jackson CD’s, Harry Potter DVD’s…
SF worldbuilding at
http://www.orionsarm.com/main.html
…or split-crotch panties?
But we humans already have non-robotic mining equipment as well as workers trained to operate those equipment. It might be easier and more efficient to say “bring us 100 tons of uranium or we blow up New York” than to deploy their own mining robots.
Yeh, but then they would have to deal with the bandersnatchi.
How about totally blasting Earth away with Vogon constructor fleets just to make way for the new Hyperspatial Express Route? No fighting, complaing or anything like that…just for the space Earth takes up?
-M
(I hope some of you out there get this…)
Well now, if you’d said “Hyperspace Bypass” instead of “Hyperspatial Express Route”, I might have understood. As it is, it just goes straight over my head. 
Then how about towels? I’m sure the Macy’s new line soft
terri-cloth spring colors would be a great asset to any alien race.
-M
Actually, it’s the opposite.
Both the Earth and the Asteroids have the same bulk composition–essentially that of Carbonaceous Chondrites. The major difference is that the Earth is FAR more “differentiated”, which is evidenced by the fact that on the Earth there is an incredible variety of different rock types (some of which include extremely high concentrations of rarer elements) whereas Asteroids and other inner planets are basically iron-nickel (core) + basalt/metabasalt (crust) +/- anorthosite (moon) +/- basaltic andesite (Mars). It’s the extreme ends of differentiation processes operating only on Earth that are responsible for concentrating these elements into economic orebodies.
And Io?
Io is certainly more differentiated than most other planets (http://astrogeology.usgs.gov/Projects/BrowseTheGeologicSolarSystem/IoBack.html), but probably still not as much as Earth. OTOH, we don’t really know yet!
Don’t worry. I’m a planetary astronomer. This means that even though I wouldn’t know olvine if it walked up and bit me on the ass, but I can identify it from its near infrared spectrum. I can also bear moderate amounts of chemistry before eventually nodding off. 
But, fractional crystallization and fluid immiscibility must happen everywhere there’s magma, no? What would make Earth (and if my reasoning is correct, every differentiated planet) unique is the particular profile of temperature and pressure conditions present in the interior, right?
How does Earth differ from Venus, then, which has a similar size and composition (but, obviously, radically different geological processes)?
eburacu45, I’d expect Io to have a whole different suite of minerals at its surface because, while it is differentiated like Earth, its composition is quite different because it formed farther from the Sun where there were a lot more solid volatiles like water ice and sulfur compounds. Also, its heating history is very different (its heat comes primarily from tidal flexing due to Jupiter, while Earth’s comes mostly from the heat of accretion and the decay of radioactive isotopes) and Io is much smaller than Earth, so interior pressures would be lower. (Maybe I’m overestimating the importance of pressure differences, though.)
Volatiles are separated by heat = distance from the Sun, that is well known, but-
Do you suppose that the entire solar system might have worked as a diferentiation machine?
Mercury is extraordinarily dense, for it’s size- do you think there could be more heavy elements in the innermost planets, which could mean that each world really has something different to offer to the alien or indeed the human prospector?
SF worldbuilding at
http://www.orionsarm.com/main.html
Well, I can’t comment on Daleks or Cardassians, but the reason the Thrints did it was because it was basically their only talent. If any sci-fi race epitomizes the concept of “one-trick pony,” I’m not aware of it. They weren’t even all that bright. Without the tnuctipun(sp?), they’d have been in serious trouble.
Er, that should read “… better eptiomizes …”