Why does a moon rock taste better than an Earth rock?
Why this joke works
An Astronomical Word Sounds Meatier
Meteor sounds like meatier, an adjective that could explain why a food seems more substantial or savory. The question asks for a taste comparison between two things nobody is treating as real food, so the absurd premise is already doing some work. The answer then substitutes a space word for the expected food description. Little helps disguise the switch because a little meatier sounds natural, while a little meteor can also describe something small and astronomical.
A closer look
A Closer Look
For spoken delivery, pronounce meteor normally and leave room for the listener to hear meatier. Do not add an exaggerated chewing sound; the imaginary taste test is only a route to the sound-alike. The written version makes the space vocabulary easier to recognize, while the comparison between Moon and Earth gives the setup a clear science theme.
Fact behind the joke
Fact Behind the Joke
NASA distinguishes a meteoroid, a small object in space, from a meteor, the luminous event produced during atmospheric entry. Material that survives to reach the ground is called a meteorite. A Moon rock is not automatically a meteor, so the punchline borrows the word for its sound rather than using it as a precise rock classification.