Was heißt »Außerirdischer« auf Englisch?

Das Substantiv »Außerirdischer« (auch: Ausserirdischer) lässt sich wie folgt von Deutsch auf Englisch übersetzen:

Deutsch/Englische Beispielübersetzungen

Glaubst du, Tom könnte ein Außerirdischer sein?: Do you think Tom could be an alien?
Tom fand es bei seinem ersten Besuch eines anderen bewohnten Planeten befremdlich, als Außerirdischer tituliert zu werden.: On Tom's first visit to another inhabited planet he found it disconcerting to be referred to as an extraterrestrial.
Tom verkleidete sich zu Halloween als Außerirdischer.: Tom dressed as an alien for Halloween.

"He claims to have slept with an alien." "Who, Tom?" "Who else?"
It may have been an unidentified flying object, but it was almost certainly not an alien spacecraft.
One day, Mary revealed to Tom that she was an extraterrestrial shapeshifter who had come to Earth several hundred years ago to study humanity.
When extraterrestrial colonists reached Earth, there was no visible trace of human life left.
What would you do if you met an extraterrestrial?
That hairy space alien doesn't speak English; he just understands it.
This landscape looks like an alien landscape.
This desert looks like an alien landscape.
The Earth is under attack by alien invaders.
I don't believe in alien life.
The alien is a small intelligent multidimensional parasite that attaches to the host's nervous system.
The green alien is humanoid and stands at 3.7 metres.
Tom wrote a book about a young man who, in the distant future, falls in love with an extraterrestrial girl, during an invasion of the earth.
I heard they found an alien artifact on the moon.
The alien shot his ray gun and blasted a hole in the spaceship's hull.
Their ideas seem totally alien to us.
This gold Rolex is an expensive watch alien to my lifestyle.
Those ideas are alien to our way of thinking.