Meanings of counter-earth in English

It was, perhaps, largely to account for such eclipses that the counter-earth was invented.

Some of the Pythagoreans say, that the splendor arises from the earth, its obstruction from the Antichthon (or counter-earth).

Their count of the heavenly bodies, including the sphere of the fixed stars, seemed to show nine, and the counter-earth supplied the missing body.