The Radio Spectrum Voltage Pacifier, or R.S.V.P. for short, was a giant transmitter invented by Professor Von Ziflin and located at Mount Moosejaw Observatory. It's purpose was to broadcast a message of greetings to inhabitants of faraway galaxies. Von Ziflin calculated that it would take centuries for the aliens to receive this message. His calculations turned out to be right. A trio of Aliens who had received the message finally visited the Earth in the year 2340.