Explain SMBC — the wiki for Saturday Morning Breakfast Cereal

This comic riffs on the astronomical concept of "clearing the orbit" -- one of the criteria the International Astronomical Union (IAU) used in 2006 to reclassify Pluto as a dwarf planet rather than a full planet. To qualify as a planet, a celestial body must have "cleared the neighborhood" around its orbit, meaning it is gravitationally dominant and has swept up or ejected other objects in its orbital zone. Pluto failed this criterion.

One character lays out two premises: (1) Pluto isn't a planet because it doesn't clear its orbit, and (2) rocket launches have gotten far cheaper. The other character asks "What are you getting at?"

The punchline appears in the caption: "NASA. You have the technology. You have the budget. We can demote Earth to a dwarf planet. The time is now."

The joke proposes that since cheap rockets could theoretically be used to put lots of debris into Earth's orbit, we could make Earth fail the same "clear the orbit" criterion that disqualified Pluto. Rather than fighting to reinstate Pluto as a planet (a popular internet cause), the comic suggests the opposite approach: demote Earth to match Pluto's status.

The humor lies in the absurd logical consistency -- if you accept the IAU's rules, then in principle you could game them -- combined with the nihilistic glee of wanting to demote our own planet. It appeals to the "Pluto was robbed" crowd by offering them a delightfully unhinged form of cosmic solidarity.