Oppositions definition of Oppositions in the Free Online Encyclopedia.

opposition, in astronomy, alignment of two celestial bodies on opposite sides of the sky as viewed from earth. Opposition of the moon or planets is often determined in reference to the sun. Only the superior planets, whose orbits lie outside that of the earth, can be in opposition to the sun. When a planet is in opposition to the sun, its elongation elongation, in astronomy, the angular distance between two points in the sky as measured from a third point. The elongation of a planet is usually measured as the angular distance from the sun to the planet as measured from the earth.
..... Click the link for more information. is 180°, it exhibits retrograde motion retrograde motion, in astronomy, real or apparent movement of a planet, dwarf planet, moon, asteroid, or comet from east to west relative to the fixed stars.
..... Click the link for more information. , and its phase phase, in astronomy, the measure of how much of the illuminated surface of a planet or satellite can be seen from a point at a distance from that body; the term is most often used to describe the moon as seen from the earth.
..... Click the link for more information. is full. This is a good time to observe a planet, since it rises when the sun sets and is visible throughout the night, setting as the sun rises.

opposition

a. a political party or group opposed to the ruling party or government

b. in opposition (of a political party) opposing the government

2. Astronomy

a. the position of an outer planet or the moon when it is in line or nearly in line with the earth as seen from the sun and is approximately at its nearest to the earth

b. the position of two celestial bodies when they appear to be diametrically opposite each other on the celestial sphere

3. Astrology an exact aspect of 180? between two planets, etc., an orb of 8? being allowed

4. Logic

a. the relation between propositions having the same subject and predicate but differing in quality, quantity, or both, as with all men are wicked; no men are wicked; some men are not wicked

b. square of opposition a diagram representing these relations with the contradictory propositions at diagonally opposite corners

5. the opposition Chess a relative position of the kings in the endgame such that the player who has the move is at a disadvantage

opposition [‚äp·ə′zish·ən]

(astronomy)

The situation of two celestial bodies having either celestial longitudes or sidereal hour angles differing by 180°; the term is usually used only in relation to the position of a superior planet or the moon with reference to the sun.

(physics)

The condition in which the phase difference between two periodic quantities having the same frequency is 180°, corresponding to one half-cycle.

opposition (redirected from Oppositions)

opposition
(redirected from Oppositions)