I think people should take a science course when they talk about aliens being on earth.
There are billions of galaxies in the universe. The nearest one is Canis Major Dwarf, which is 25,000 light years away.
One light year is the distance that light travels in a year -- about 6 trillion miles.
So the nearest galaxy is 6 trillion miles x 25,000.
Yet people think that some little green men in a space ship came here and live among us and that "the government" is keeping it secret and no one has seen any evidence of it.
Right.
The governments of all the world are keeping this a secret.
They couldn't even stop Eric Snowden.