About the Buddha Preaching that we Humans are Aliens What I have heard is, the Buddha has preached that we Humans are the Evolution of Alien life which had arrived on earth many years before
Could this be correct and did he preach so and in which SUTRA is it recorded ?
Thank you
The Sutta you are looking for is Agganna sutta.
In the second part of the Sutta, the Buddha tells the story of how human beings came to dwell on Earth.


  The Buddha said that sooner or later, after a very long time, there
  would come a time when the world(universe) shrinks. At a time of contraction,
  beings are mostly born in the Abhassara Brahma world. And there they
  dwell, mind-made, feeding on delight, self-luminous, moving through
  the air, glorious — and they stay like that for a very long time. But
  sooner or later, after a very long period, this world begins to expand
  again. At a time of expansion, the beings from the Abhassara Brahma
  world, having died from there, are mostly reborn in this world. Here
  they dwell, mind-made, feeding on delight, self-luminous, moving
  through the air, glorious — and they stay like that for a very long
  time...