Maybe Hawking doesn't want us to contact any MORE aliens because h is in fact the advance party of an invasion of some other space aliens.
Think about it. This guy knows an awful lot about space and time though he has never been there. He has to sit in a wheelchair (possibly because his alien muscles cannot adapt to our gravity?) He must use a computer to speak to us (possibly because his alien physionomy is incapable of reproducing human speech!) I know he is supposed to be suffering from a degenerative illness. Michael Jackson was supposed to have vitiligo (and what about Sammy Sosa?) Has anyone spoken to his doctor or seen his medical records?
