People have claimed throughout history that aliens exist. There have been many sightings of UFO's recently. So does this mean that there are other living life forms in our galaxy? To be honest I don't know what to think. I don't believe that we are the only ones in the galaxy. It has taken our planet a long time to modernize and now we develop advanced technology that will let us explore other planets. We may find out if there are other life forms in the next couple of years.
It has been said that the UFO sightings are actually airplanes being tested by the military and they say its a UFO so they can divert attention away from themselves. That changes a lot about what we think about alien spottings in the past. What if the government lied about that too? I personally believe that we cannot take our government's word. They lie to us so we don't panic and cause chaos. If people found out that there were actual aliens, then chaos would enfold. In movies, aliens are potrayed as hideous creatures that want to take over our world. I personally believe that in the future, our government will be the one threatning their planet like in the movie "The Avatar." Look at how Africa was treated and now the Middle East. I really don't want to see that day come. We'll we percieved as villians in other planet's history. One planet is enough.

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The only "aliens" I know of are evil people, not worthy of being called "human" as of HU = Holy and Universal. In that sense I believe in "aliens" - living not only in space, but also on earth.
The decent people are "humans." And they can not only be found on planet earth, but also are roaming the galaxies, riding on their technological achievements which are light years advanced of our own. I prefer calling them "extraterrestrials" instead of aliens.
We must also bear in mind that our own species on earth are "extraterrestrials" as well, even though we do not roam the universe like others.
A long time ago all human species were colonized here on earth by our forefathers on their intergalactic space craft. Unfortunately for us, we have just not kept a proper historical record of it.
You mention about the movie “Avatar”, on that movie, Earthlings were the far more advance races in terms of technology compare to beings from planet Pandora.
I’m sure, before humans reaches that planet Pandora, those living beings there already wonders if there are other civilizations aside from them, since they don’t have any technology just to detect if there is an existence of a planet called “Earth” and if there are living creatures on earth or none.
But the current situations regarding advance technology are not that far advance.
We only depend on Hubble Space Telescope and a fly-by satellite mission seeking if there are other civilizations out there; maybe we need more years to wait like until year 2488 or year 6764, then who knows?