• We are currently working on a new series canon policy page. Please join the discussion by clicking this link!
  • New article from the Springfield Shopper: Season 33 News: A ruthless debt collector targets Flander this November!
  • Wikisimpsons needs more Featured Article, Picture, Quote, Episode and Comprehensive article nominations!
  • Wikisimpsons has a Discord server! Click here for your invite! Join to talk about the wiki, Simpsons and Tapped Out news, or just to talk to other users.
  • Make an account! It's easy, free, and your work on the wiki can be attributed to you.


Wikisimpsons - The Simpsons Wiki
Radioactive Man Icon.png The contents of this article or section are related to the Radioactive Man universe. They are considered fictional in The Simpsons.
Animal Information
Species: Cow
Color: Blue
First Appearance: The Little Boy with the Big Dream

Moon-Cow is cow living in space.


When Radioactive Man heard Danny McKay talking about a Moon-Cow in his dreams he realized that Danny was in another part of the galaxy, in the uncharted space between a grown-up's world and a child's dream. Radioactive Man then flew to that part of space and passed Moon-Cow. Later, Moon-Cow flew over Windy and Mrs. McKay when they were in that part of space.

Behind the Laughter[edit]

Moon-Cow is a reference to the nursery rhyme "Hey Diddle Diddle", in particular the line "the cow jumped over the moon".