I just strongly doubt that. Firstly, heaps of people would be dressing as aliens for Halloween and thus talking about it.
Secondly, there's just way too many follow up questions, about them, their culture, their home, their tech, their goals, their language, their biology, the impact they've already had in our history, who knew and who didn't, etc.
So many fields would begin looking into it and throwing up new angles and facts for people to chew over.
Just think of how much time christians would devote to converting aliens to jeebus.