Quote from: username18333 on November 19, 2014, 05:22:25 AM

Quote from: Ray Villard link=http://news.discovery.com/space/alien-life-exoplanets/time-to-plan-for-a-millennium-mission-to-alpha-centauri-130617.htm

The impressive planet inventory take by NASAs Kepler space observatory, combined with other research, has taken us down the road to concluding that, on average, every star in the Milky Way galaxy has at least one planet. Whats more, Earth-sized planets are far more common than giant Jupiters.

Planets exist there, and we do not have the ability to observe planets of our size; therefore, it is entirely possible that the civilizations described above do, indeed, occupy planets akin to our own both in size and and orbital zone. As well, considering the close proximity of some of these stars (α Centauri is our nearest solar neighbor), it is entirely reasonable to expect them to have found or heard of us in exploring their most immediate, solar surroundings (upon, of course, acquiring the ability and desire to do so).

Absolutely; as I've said a number of times now, I do believe life exists elsewhere in the universe - in fact, I would be surprised if it didn't come from more varied environments than just worlds with Earth-like conditions, meaning that, to me, the existence of extraterrestrial life seems almost certain.

That said, we still need proof. Anyone can come up with a reasonably convincing story of something that can't be disproved with current knowledge, and try to pass it of as truth.

Quote from: username18333 on November 19, 2014, 05:22:25 AM

Quote from: Ray Villard link=http://news.discovery.com/space/alien-life-exoplanets/time-to-plan-for-a-millennium-mission-to-alpha-centauri-130617.htm

Nevertheless, Its not too early to think about the a millennium-long project to visit and colonize the star system. I cannot imagine a bolder step for the evolution of mankind. The project will cost untold trillions of dollars spent across many generations. But it will establish us as an interstellar species, that is for all practical purposes, immortal. This would be an evolutionary step as profound as when Earths first sea creatures ventured onto land.

However, it should not come as any surprise that the people, Homo sapiens, that exterminated Homo erectus and the Neanderthals would instill certain reservations within prospective visitors and motivate them to maintain a general ignorance about their existence among that people.

Quote from: Ray Villard link=http://news.discovery.com/space/alien-life-exoplanets/time-to-plan-for-a-millennium-mission-to-alpha-centauri-130617.htm

Could intelligent life be there too? Unfortunately, in a lousy coincidence, the star system is too far south to be observed by the powerful Arecibo radio antenna in Puerto Rico, or the new Allen Telescope Array in northern California, that can easily look for any artificial radio transmissions.

Humans are indeed an extremely aggressive species in a number of respects; but I don't believe there is a conspiracy to keep alien visitors hidden from the public. Rather, I think it's more likely that this whole subject (and a few controversial others) are exploited to keep the population distracted - so, a form of population control, if you will.

EDIT: Just noticed you added something else to your answer, and updated accordingly.