The radio signal came from the ice world. From orbit we could detect nothing but frozen water.
We finally decoded the message: it was a pressure-temperature phase diagram for ice. We knew of twenty or so forms of ice but this diagram had almost fifty.
They were telling us what they were made of.
We debated sending a response. But how do you explain “carbon” to H₂O?
Consider this a friendly, local pub. Make yourself at home, bring your friends, have a good time! Meet new people, have a laugh, enjoy the ambience, and the Oxford commas.