The International Astronomical Union (IAU) has declared that the trans-Neptunian dwarf planet formerly dubbed 2005 FY9, or "Easterbunny", will henceforth be known as the equally silly "Makemake".

Makemake, discovered in 2005 by a team from the California Institute of Technology led by Mike Brown, is the fourth officially-recognised dwarf planet in our solar system, and the third plutoid, joining Pluto and Eris in the small fry club hanging around beyond Neptune.

Since an object's discoverer has the privilege of naming it, it fell to Mike Brown to christen his baby. He explained, quite possibly after a light whalesong and joss-stick session: "We consider the naming of objects in the solar system very carefully. Makemake's surface is covered with large amounts of almost pure methane ice, which is scientifically fascinating, but really not easily relatable to terrestrial mythology.

"Suddenly, it dawned on me: The island of Rapa Nui. Why hadn't I thought of this before? I wasn't familiar with the mythology of the island so I had to look it up, and I found Makemake, the chief god, the creator of humanity, and the god of fertility. I am partial to fertility gods. Eris, Makemake, and 2003 EL61* were all discovered as my wife was 3-6 months pregnant with our daughter. I have the distinct memory of feeling this fertile abundance pouring out of the entire universe. Makemake was part of that."

In case you're wondering, the solar system's quartet of dwarfs is made up by Ceres, which doesn't get plutoid status since its orbit is smaller than Neptune's. ®

Bootnote

*2003 EL61 is a rather stange Kuiper Belt object, shaped like a rugby ball and spinning like it's been well and truly kicked into touch. There's more here.

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