Henson's Comet is a celestial object found in Earth's solar system.
When Carlos visits The Nursery in the Muppet Babies episode "Muppet Space Camp", the babies get permission from their parents to stay up late for the arrival of Henson's Comet.
Planning to watch it from the backyard, Summer Penguin wishes they could see it up close. Carlos offers to let everyone use his telescope, but Baby Gonzo insists they fly into space for an enhanced experience. After Carlos expresses anxiety over making the trip, the babies run him through Muppet Space Camp to get him ready for the voyage. Following a vigorous training routine, the babies are treated to a close-up view of the comet from their spaceship.
The tail of Henson's Comet, made up of ice and space dust, emits a spectrum of colors that make it look like a rainbow streaking against the vacuum of space. The comet's namesake is Jim Henson, creator of the Muppets.