Came across it on t.v. the other day and decided to watch it since I haven't in such a long time...boy was that movie about the struggle for faith! I just couldn't decide whether the movie was for or against Atheism. It seems because of the ending that they were attempting to convey believing in God was not only necessary but right. What do you guys think?
Eric, I think you're overlooking the food factor - if life in the universe is as rare as it appears to be, and a species has eaten everything edible on its own planet, why knows?
Even if they get to earth there is no guarantee that anything that it is here would be food for them. That assumes that their species is reproducing beyond their means.
My assumptions revolve around the idea that a species this advance would almost by necessity rid itself from the most basic human problems we face in order to thrive.
That involves: They can harness energy to maintain a highly technological civilization without altering their environment (Maybe fusion or other renewable sources), has had achieved something close to world peace which I think can only be reached through rational and benevolent ways of life, and the basic necessities like food and whatever they may drink are not an issue.
Our planet would not have an overpopulation issue, if people where better educated and poverty was less prevalent.
Unseen, the hydrogen atom is the most plentiful of all of the elements in the universe - why on earth, literally, would they need to come here and separate H2O molecules, just to get hydrogen?
You can ask them when they get here. I suspect they'll say that Earth is one of the few planets with such large puddles of the stuff.
Actually the planet "GJ 1214b" is basically a water world. Also There is good reason to believe that underneath Jupiter's moon Europa there is an ocean kept in liquid form through tidal heating. Water is very common in the universe, since is made of the most common atoms.
Frankly, I'm leaning toward an Improbability Drive, and there are an abundance of those.
As for a hydrogen drive, building vents into their craft that could act as hydrogen collection scoops, then zipping through the nearest gas cloud would certainly be a lot simpler and more logical than hoping they'll locate a waterworld before they ran out of gas.