Superior and Inferior
As seen from a planet that is superior, if an inferior planet is on the opposite side of the Sun, it is in superior conjunction with the Sun. An inferior conjunction occurs when the two planets lie in a line on the same side of the Sun. In an inferior conjunction, the superior planet is "in opposition" to the Sun as seen from the inferior planet.
The terms "inferior conjunction" and "superior conjunction" are used in particular for the planets Mercury and Venus, which are inferior planets as seen from the Earth. However, this definition can be applied to any pair of planets, as seen from the one farther from the Sun.
A planet (or asteroid or comet) is simply said to be in conjunction, when it is in conjunction with the Sun, as seen from the Earth. The Moon is in conjunction with the Sun at New Moon.
"Quasiconjunctions" are also possible. In these situations, a planet in retrograde motion – always either Mercury or Venus, from the point of view of the Earth – will "drop back" in right ascension until it almost allows another planet to overtake it, but then the former planet will resume its forward motion and thereafter appear to draw away from it again. This will occur in the morning sky, before dawn. Else the reverse may happen in the evening sky after dusk, with Mercury or Venus entering retrograde motion just as it is about to overtake another planet (often Mercury and Venus are both of the planets involved, and when this situation arises they may remain in very close visual proximity for several days or even longer). The quasiconjunction is reckoned as occurring at the time the distance in right ascension between the two planets is smallest, even though, when declination is taken into account, they may appear closer together shortly before or after this.
Read more about this topic: Conjunction (astronomy)
Famous quotes containing the words superior and/or inferior:
“At length he would call to let us know where he was waiting for us with his canoe, when, on account of the windings of the stream, we did not know where the shore was, but he did not call often enough, forgetting that we were not Indians.... This was not because he was unaccommodating, but a proof of superior manners. Indians like to get along with the least possible communication and ado. He was really paying us a great compliment all the while, thinking that we preferred a hint to a kick.”
—Henry David Thoreau (1817–1862)
“The world proceeds from the same spirit as the body of man. It is a remoter and inferior incarnation of God, a projection of God in the unconscious.”
—Ralph Waldo Emerson (1803–1882)