The Answer is Simple: "Klaatu barada nikto"

What else? "E.T Phone Home"????

Or maybe this?????



If we spent half as much time worrying about what we would say to aliens & more time worrying about what we will say to God when we face the final judgement I think a lot of our money would be much better spent where it should.

Besides, we already do know what to say if we really want to tak to a being from heaven. It goes "Our Father who art in Heaven. . . ." In other words, why do you think Jesus came to Earth?, to enable us to not only know how to communicate with God, but to "know, love & serve Him in this world, & be happy with Him in the next" as the old Baltimore Catechism said.

Jesus, John the Baptist, the prophets, the Apostles & many others have been showing us how to communicate with the 1 being we need to communicate with. & like I said, if we would spend time responding to the "Word" we have already been sent. . . .

How Should Earth Respond When Aliens Say Hello?

If mankind ever does receive a signal from extraterrestrials, one of our first decisions may be what to write back.
As director of Interstellar Message Composition at the SETI Institute, psychologist Douglas Vakoch has thought a lot about this question.
"The challenge of constructing any interstellar message is trying to anticipate what you and your recipient have in common," Vakoch said. "One thing we can guarantee is they won't be native speakers of English or Swahili or Chinese."

And the same problem applies to any incoming message to Earth.
"It's very reasonable to think that we will know there's an extraterrestrial out there, that we will have a message that is distinctly artificial, but that we won't be able to decipher it," Vakoch said.
So choosing a language and means to communicate is just as difficult as figuring out what you want to say. A language based on mathematics and scientific principles is a good idea, Vakoch said, because presumably if aliens are advanced enough to send or receive a signal across the abyss of space, then they'll have some scientific understanding.