If the question is asking about foreign visitors (both legal and illegal) to a country of which they are not a citizen -- the answer is that the legal aliens are issued ID cards or papers of some type which identifies them as being legally admitted to the country - usually for a set predetermined length of time.
The illegal aliens have no such documentation issued to them and it should only be a matter of time before it becomes obvious who they are since it is almost impossible, in this day and age, to live and function without some type of legal government document.
If the question is actually about the extraterrestrial type of aliens - I'm sorry to say that there are no such plans in place.
Aliens are not known to exist, so good luck. I think you mean ET type aliens, not the ones flooding over our southern border. No problem running into those!
Since we have not meet extraterrestrial aliens, we do not know. Yet.
Nope.
The would have war with us
No.
December 21, 2012
The U.S. Government has already classified over 55 species of aliens.
yes you just have to past missions
at pizza planet in a crane game
no, but apparently he had claimed to meet "supermen" which are extraterrestrials
That depends, you go meet one, im sure you will find out then :)
You can't.The only way to meet aliens to have a male sim get abducted and when he comes back,your sim will be pregnant.You won't notice it,but like female sims,in a few days you'll have a baby alien.
Although there are many reports about aliens from outer space, we have no definite, confirmed contact with any such aliens, and therefore it would be impossible to say whether aliens would prove to be useful or destructive, if we actually were to encounter them. We will find out when and if we meet them.