Sky Whisperer:
"Did you hear about the snail who took up pogo-sticking? No? Neither did gravity."
Astro Poet:
"The stars are just doing their taxes, filing under 'cosmic brilliance exemption'. Ever tried claim a nebula?"
Lunar Tourist:
"I tried to book a room on the moon but the WiFi was all booked out by a rogue cluster of computer mice."
Gravity Defyer:
"Went to make a cup of tea, but the kettle floated off in protest. Said it had a date with Jupiter."
Black Hole Enthusiast:
"They say if you listen closely you can hear a black hole humming a toon... except it's really just buffering eternity."