You know, don't you think
once an astronaut leaves the PLANET,
The Big Bang Theory Season 9, Episode 23
Or as I call it, Planet Bollywood.
The Big Bang Theory Season 2, Episode 4
...when the PLANET Krypton exploded.
The Big Bang Theory Season 2, Episode 11
...your best bet would be
to kill all the other men on the PLANET.
The Big Bang Theory Season 2, Episode 9
Maybe it's a new PLANET.
The Big Bang Theory Season 9, Episode 12