Billions of years ago, Urlum and Neidon were joined by another ice-giant. However, this ice-giant was unfortunate enough to encounter Sarnus very early in its live, and it was ejected into the inner solar system, well within the orbit of Moho. Scientists on Kerbin were extremely curious as to why Moho has such an inclined and elliptical orbit, but a suspicion led to the discovery of a new planet, called Heidon (It was named after the evil twin of Neidon). The planet is scorching hot and has a pretty ring system.
Requires Kopernicus:
Download here: https://kerbal.curseforge.com/projects/heidon-mod
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