Two aliens land on the earth, near L.A. They get out of their aircraft, take their scanners, and start exploring their surroundings. After walking for a while, they suddenly see a L.A.P.D. cop lying in the middle of the road.
So the first alien says, "UX251, do you see the object on the ground?"
"Yes," answers the other, "what could it be?"
"I don't know, UX251, pass the scanner and see if we can retrieve some data on it."
So they scan the object. "No data available, UZ11, what will we do now?"
The alien thinks for a while, picks up the cap, and puts it on his head. "What could this object possibly be?" asks the other one. "I don't know you weirdo," says the alien, "but I sure feel like beating the crap out of you."