Ancient philosophers suspected an anti-Earth existed opposite an "eternal fire" in a geocentric model. More modern philosophers suggested it could be behind the sun in a heliocentric model. Science had proven a Counter-Earth to be impossible... but what if?

The counter-earth is a planet with a height-map that is Earth's, except for two major differences. One: It's inverted east/west. Two: It's inverted High/Low.

The mod does not require Real Solar System to be used, but If you don't use RSS it will be in a strangely inclined orbit far outside the distance of Eeloo. The mod is meant to be played with RealSolarSystem, and as such has had its orbital characterics modified to become identical to Earth's, except 180 behind in the orbit (on the opposite side of the sun.)

Side note on naming: The planet is named Antichthon, or "Opposite of The Earth." It is important not to confuse it with a Chthonian planet, a type of exoplanet with it's atmosphere being stripped away. Those planets get their name from the same greek word "Of the Earth" except in the context of those exoplanets "of the Earth" refers to greek deities in the underworld.