Those born outside the earth, not on earth, are called aliens.There is a lot of disagreement among scientists about aliens.
Some people think that there is nothing to say about aliens. Everything is imaginary.Some people claim that there is life outside the earth.
However, there is no clear evidence of this.However, there has been a search for a place to live outside the earth. There is also the existence of water. But no animal has been found.
Many people think that when it becomes impossible to survive on earth, people will start living in all those places outside the earth.Since no trace of the existence of aliens has been found, there is much disagreement about their shape.
And the word alien has spread to ordinary people for various science fiction movies.
You're right. "There is a lot of disagreement among scientists about aliens." There is no clearance about aliens.