Lost comet Comet Shoemaker–Levy 9, which collided with Jupiter in 1994. Lost comet A comet is "lost" when it has been missed at its most recent perihelion passage. This generally happens when data is insufficient to reliably calculate the comet's orbit and predict its location. The "D/" designation is used for a periodic comet that no longer exists or is deemed to have disappeared. Lost comets can be compared to lost minor planets, although calculation of comet orbits differs because of nongravitational forces, such as emission of jets of gas from the nucleus. Some astronomers have specialized in this area, such as
The Elves and the Shoemaker cartoon short "Holiday for Shoestrings". In the "Due South" episode, "The Deal", Det. Ray Vecchio vaguely recollects this story when discussing a poor cobbler with his partner, Constable Fraser. In "", a spinoff miniseries of the Vertigo comic-book series "Fables", the shoemaker appears as an employee in Cinderella's shoe store, while the elves are the builders and suppliers of the store's inventory. "Muppet Classic Theater" had a version where a shoemaker (played by Kermit the Frog) faces ruin until his livelihood is saved by a group of philanthropic entertainers (played by The Elvises) who, naturally, make only blue suede shoes.