The first documented alien encounter happened in 1947. A businessman, Kenneth Arnold, was flying his small plane when he encountered nine objects, traveling at a high rate of speed in the Ranier, Washington area. He described them as moving similar to saucers on water, and the term 'Flying saucers' was born.
All planets other than Earth could be considered alien. Earth is the only planet known to harbor life.
The astronomer, Oglivy
"UFO" does not mean alien spaceship. So far there is no scientific reason to think even one alien spaceship has ever landed on Earth. UFO just means "I saw something in the sky and I personally don't know what it was."
There are no authentic and verifiable instances of any alien coming to earth. That being so there are no details of such an incident with the exception of conspiracy theories or fantasy tales.
The alien land bill was a law passed in 1913 that prevented Japanese people from owning land in California
When the metric alien landed on Earth, he said, "TAKE ME TO YOUR LITER"
There have been many speculations on if an alien being has been on earth. There have been no confirmed reports on aliens on earth.
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The first spacecraft carrying a human to land safely was Vostok 1 carrying cosmonaut Yuri Gagarin.
Unsealed Alien Files - 2012 II Alien Earth 2-12 was released on: USA: 4 November 2013
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Neil Armstrong.