“It is not when truth is dirty, but when it is shallow, that the lover of knowledge is reluctant to step into its waters.” -Friedrich Nietzsche

Out beyond Neptune, the last of our Solar System's gas giants, the icy graveyard of failed planetesimals lurks: the Kuiper Belt. Among these mixes of ice, snow, dust and rock are a number of worlds -- possibly a few hundred -- massive enough to pull themselves into hydrostatic equilibrium.

Image credit: Wikimedia Commons user Lexicon; modified from the NASA original.

The most famous among them are Pluto, the first one ever discovered, and Eris, of comparable size but undoubtedly more massive. But there's an even larger, more massive object from the Kuiper Belt than either of these, yet you never hear about it: it's Triton, the largest moon of Neptune!

Image credit: NASA / Jet Propulsion Lab / U.S. Geological Survey, via Voyager 2.

Find out why Triton really is a Kuiper Belt object, and what makes it so special, on today's Throwback Thursday!