
The Milky Way is a GALAXY in space.
The Big Bang Theory Season 6, Episode 5

Wait. In The Hitchhikers Guide
to the Galaxy...
The Big Bang Theory Season 6, Episode 8

Hitchhiker's Guide
to the Galaxy.
The Big Bang Theory Season 7, Episode 6

Which is also called
The Hitchhiker's Guide to the Galaxy.
The Big Bang Theory Season 8, Episode 8

Now, in the beloved novel
Hitchhiker's Guide to the Galaxy...
The Big Bang Theory Season 8, Episode 8