Primary planets

(Astron.) See the Note under Planet.

See also: Primary

References in classic literature ?
They have likewise discovered two lesser stars, or satellites, which revolve about Mars; whereof the innermost is distant from the centre of the primary planet exactly three of his diameters, and the outermost, five; the former revolves in the space of ten hours, and the latter in twenty-one and a half; so that the squares of their periodical times are very near in the same proportion with the cubes of their distance from the centre of Mars; which evidently shows them to be governed by the same law of gravitation that influences the other heavenly bodies.
According to the study, the possibility of the dwarf stars entering the boundaries of the solar system might potentially disturb the trillions of comets orbiting in the Oort cloud beyond the primary planets. This might send many comets into the inner solar system and has the potential to hit Earth.
You have two primary planets, and the Free Radical of this pair, Uranus, powers its way into the most vivacious part of your solar horoscope to begin a 7 year residency.
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