You do not want stephen hawking. He's actually set up a bounty on aliens because he truly believes any alien life forms coming down would be in his words "similar to when Columbus first met the native americans". He thinks they would either naturally be hostile towards us or bring extra terrestrial diseases that would wipe us out. So he set up a bounty of sorts.
Chances are that there is a dusty folder in a forgotten and disused filing cabinet in the corner of the White House basement that is simply labeled, "Visitation Contingency" and their names are already in it.
rly
they;d all be like
y y'all talkin if u can get this robot speaker thang