Yes, but they have an entire solar system, all out of our reach, filled with whatever resources they think they need. Hydrogen? Oxygen? Water? The Oort cloud has plenty. Nitrogen? Plenty of Methane out there too. Heavy metals? Lots in the asteroid belt.
In short, there is absolutely NO NEED for a habitable planet, or bothering with the inhabitants thereof, in order to get all the resources one needs in space. Short of food, and you kinda have to presume they’re bringing their own biological needs with them and that they don’t want to risk interaction with alien bacteria or food stuffs.
It’s kind of like those sci-fi movies are bullshit where they colonize a new planet because of some ecological disaster or lack of resources on their planet. It will probably always be easier and more cost effective to fix whatever is wrong with your planet than to colonize a new one light years away.
The problem though, is that we are trying to extrapolate an interstellar race’s technology from our existing knowledge. It’s like prehistoric men saying you can’t cross the ocean because you can’t build a canoe big enough to hold the manpower and supplies you will need for the crossing. Such a thing is routine for us because we have materials and power supplies they couldn’t comprehend.
That seems a little pessimistic. In theory we could build a thermonuclear pulse ship TODAY that could go about 3% of light speed and slow to a stop again. And I liked the premise of the novel Footfall: the aliens were refugees, who’d lost a civil war in their home system and decided to flee. Once they got here that was it, they were committed to staying here. In fact, fleeing whatever is the local equivalent of the Alliance is probably one of the most compelling reasons for interstellar travel.
Here’s one bit I’ll predict- the end of racism. Racism is only possible when there’s an identifiable “other” to judge against. But the black guy down the street is practically identical to the KKK guy who is discriminating compared to the aliens who’ve showed up. For once, I think that we’d be able to get together and have an ingroup of the entire human race, and actually work in concert for once. Whether that concert is in any way productive remains to be seen, but I think human co-operation would drastically increase.
Bad. First they’d abduct you and steal all your ova, then return you, barely alive. Once you recover from the coma you and all your friends get cancer. Live through that and you’ll discover they used the ova to create alien-human hybrids that’ll be able to survive when they return to enslave us all in five years. By the time you discover your poor hybrid offspring the little waif is on death’s door and up and dies on you. Now you’ll never have children! Then they steal your boyfriend…
Race is overrated. I am sure that the dominant class of both species will quickly form ties to ensure their continued dominance over their respective minions.
But only an analogy. Just because there is a gulf of incomprehensibility between stone age technology and our own, doesn’t necessarily mean there is a similar gulf to be crossed in advance of our own (or rather, anything on the other side of that gulf). There may actually not be any possible technology that is to ours as ours is to the dugout canoe.
This is pure conjecture thinking a civilization more advanced than ours could not use connections between areas of spacetime. It’s not right for us to assume through what we know that it is not physically possible. To our race it is not physically possible, but then we are not talking about our race our we. I think it naiive of us to think they could not use that form of space travel.
No we cannot. This is absurdly beyond present propulsion technology, and no one but Carl Sagan and a few science fiction authors–cetainly no one who worked on the original Project Orion or its successors–believed that nuclear pulse propulsion is suited for transit between stars, never mind the manifest other problems with interstellar transit. As a method of travelling between planets, an Orion- or Daedelus-type propulsion systems have orders of magnitude too low in specific impulse and exhaust velocity to attain the speed you claim.
Urk? I’m not sure you understand what those words mean? It is “pure conjecture” to talk in terms of real physics rather than ficitional space opera?
It could be that we’ll discover some new principle that allows for science fiction-y “warp drive”, but we have good reasons to believe that even if such a thing is possible that it would take enormous energies–on the order of that put out by a star–to make it work at all. Any civilization that could command such energies isn’t going to be running around in spandex tights zapping at each other with ray-guns and quantum torpedos, and they’re probably not going to have much interest in abducting people to stick probes up their bums or strip mine the Earth for resources more readily and bountifully available in space.
I’m going to have to flatly contradict this statement. There are numerous cites saying that Freeman Dyson himself theorized on the use of a “super” Orion for interstellar travel.
Cite them, then. And in any case, it remains that the propulsion capabilities of Orion are insufficient to attain “3% of light speed”, nor would such a trip be sustainable with anything like current spacecraft lifesystem capabilities.
As to whether space aliens would be good or bad, it is completely impossible for use to speculate as to their intentions, desires, or capabilities with even the remotest of authority.
There is no way for us to know that the order of magnitude of alien technological and cultural superiority over our own wouldn’t be any less than that which we observe between an ant colony and the microprocessor factory against which it abuts.
Maybe at first but unlikely in the long term. We are people after all. We’ll just factionalize along different lines. One group will want to work with them, one will want to fight them with force, one will want to oppose them peacefully, one will be sure that they are the anti-Christ and and equal group will think that they’re the Messiah.
I agree-Interstellar travel is beyond us, at any level of technology we could imagine. About the only way we could do it,is to hollow outan asteroid and turn it into a dwelling which will be inhabited for thousands of years. Face it-a technology level that allows for speeds of 5% of c, is going to be so well off, they have NO need to colonize other planets. Any curiosity they have is going to purely scientific. As for invading earth-this planet is a small sized planet, orbiting a small sun. There must be better places to go to!
I do not know or hang in circles of people who know much about physics and certainly do not claim to. If you want to build a tree house or nice rock wall come see me.
What I’m saying is that you seem to be discounting an alien species ability to do something we clearly cannot and assume will never be able to do with our current understanding. That’s all. I’m not talking about aliens using zappers and ray guns, I’m merely stating that we cannot say for sure that they do not know how to travel through space in an efficient way like using a worm tunnel or some other form of travel. Or if they even need to travel at all - perhaps they have a different form of getting around we could not fathom at this time.
That’s all I am saying. Use your wit and your knowledge of physics or whatever your knowledge base is and try and imagine a way for a species in another galaxy to get to our planet and state what that is…That’s all I’m asking. Maybe it’s stasis like has been postulated up thread. Who knows?
For starters, the book Project Orion: The Atomic Spaceship 1957-1965. by Freeman’s son George Dyson. Or The Starship and the Canoe by Kenneth Brower. I used the 3% figure as conservative from some unattributed quotes saying that the thermonuclear version of Orion (with a pusher plate kilometers in diameter and using megaton bombs!) could achieve 6-8% lightspeed, since I didn’t know if they meant accellerate only or accellerate and decellerate. And finally, sustainable life support for a space ark is another issue entirely, which I leave to others.