The conjunction is perhaps the most powerful aspect and may be seen as analogous in meaning to the New Moon, which occurs every month when the Sun and Moon come together. The sign and house position where the conjunction occurs will have great significance as well. When we divide the circle by two, we have the opposition. At the time of the Full Moon we have an opposition between the Sun and Moon. At the Full Moon we can see at night, and the opposition brings the capacity for objective awareness.
Planets involved in opposition aspect tend to reflect off of one another, to mirror one another.
We become aware of others through the opposition aspect, and this aspect has a great deal to do with our relationships. As a young astrologer, I remember a teacher saying that when we are ready to make headway in this life, we are ready to work with our oppositions. The trine aspect is created by dividing 360 by 3. If we drew the lines of the trine onto a chart, we would see a perfect triangle, an image long associated with harmony and receptivity. Trines between planets may indicate gifts, natural talents, rapport and support between the functions of whichever planets are involved.