I hate to break it to you, but Avatar wasn't actually about other worlds in the distant future. The story is an allegory for Earth right now and in recent history.I'm sorry for not making my point more clear, I am not against space travel or science in any way in fact I use a lot of scientific principles in my religion, but what concerns me about humans is the arrogant attitude they think they can own everything they see.
If you haven't seen the movie Avatar please check it out because I think it addresses my concerns with great symmetry.
In the year 2154 the earth has depleted most of its natural energy resources and found a wonderful energy source referred jokingly by Aero Space Engineers as unobtainium.
This unobtainium resource is rightfully guarded by the Navi Tribe that viewed this resource as a sacred object which is part of the life force of the moon they inhabit. The only thing the humans seen from unobtanium was a fuel source, but it was a sacred element that gave life to the moon the Navi Tribe was from.
In my personal opinion I believe we should be humble space travelers and not dominant conqueror's of our environment, other wise we are going to make the same mistakes our ancestors made by destroying any habitat and resources we come into contact with.
Most indigenous cultures have a sacred bond with the planet and adhere to the framework of maintaining sustainability by being in harmony with the sacred balance needed between humans and nature.
Dominating imperialistic cultures seem to follow the same pattern of reducing a planet's sacredness by thinking of it as a resource to exploit for their own use without regards to the consequences of their actions.
If our main objective is to venture out to space to reach out to the sacred cosmos to learn from its teachings to become better people then sign me up for that wonderful ride of discovery.
If our objective is to dominate and exploit the resources we find, we are doomed and haven't learned one thing from our past!
The final point I would like to make before I depart is that we haven't even addressed the ethical issues we may encounter as our technology increases. What are we going to do if we encounter a primitive alien life as we boldly lay claim to a planet we landed on? Are we going to wipe them out so we can establish a colony? Are we going to have a prime directive like Star Trek to honor all life we may come into contact with and not interfere with their culture? Although I have very Shamanistic beliefs that everything is sacred I hope it is shown I can see a very secular and practical view to space travel, I am just wondering though: what is our purpose for traveling in space?
Most science fiction is actually a commentary on issues that were relevant in the time when it was written.