Lothar the Grouch
From Muppet Wiki
Lothar the Grouch is a grouch from the seventh moon of the planet Zurkon. He sends a hologram message billions of miles to Oscar the Grouch on Earth via R2-D2 in Sesame Street Episode 1364.
The message is "Oscar the Grouch, get lost!", to which Oscar replies "What do you know? There is intelligent life in outer space."
