Muppets From Space Easter Egg - Pigs in Space

"Pigs in Space", as with other Muppet Show sketches, consisted of regular Muppet characters playing different parts. The two main pigs in Pigs in Space were Link Hogthrob and Miss Piggy. Both were regular Muppet characters and existed beyond that re-occurring segment, so I'm not sure if this was actually a reference to the space theme. (NOTE: since Jim Henson's passing, some of his characters such as Link the Pig & Rowlf the Dog, have been reduced to non-speaking appearances in large crowds for the last few Muppet movies, so this isn't uncommon).

Miss Piggy, Link Hogthrob and Dr. Julious Strangepork often make cameos in other Muppet projects, this is hardly an egg. I am pretty sure the one you are talking about is Link too, and he has appeared in every Muppet movie in non-speaking roles (look for him at the Gong on the pig's island in Muppet Treasure Island).