Hi! I just discovered the astrological section on AT, that's great! I love astrology
Let's say that A has a moon in Virgo (1 degree Virgo) and B has an Aries' moon at 26 degrees. The aspect formed between the two moon is a trine (wide orb but still, about 5 degrees).
So the ''trine aspect'' is supposed to be an harmonious aspect between 2 moons. However here, the moon placements are in element that are considered inconjunct (quincunx).
What would be the effect here felt by these 2 people? Does the trine ''feeling'' is attenuated by the element of the moon (i.e. inconjunct)?
Other example:
A= Mars in Pisces (29 degrees)
B= Venus in Sagittarius (0 degrees)
Mars and venus are making a trine aspect (by less than 1 degree) but the sign are square to each other.
Again, does the trine aspect is lessen because of the square sign?
There's not an easy answer to this. You will find a lot of dsagreement between Astrologers. There are two key points in your question.
The easier of the two is the 'orb' that is used for an aspect. Here you have a difference in degree of five degrees, in the first example and 1 degree in the second. Most Astrologers would treat this as being within orb.
The second issue is the one that you're really concerend about, the difference between aspects by sign and by degree.
The original Hellenistic system had both but aspects by degree were given very narrow orbs - about three degrees (except for the Moon which had 13 degrees). Much of the meaning and interpretation of trines, squares and other aspects comes from the nature of the signs, by element, mode and gender. Trines share element and gender by sign, which is seen as providing the harmony. A further reason is that Jupiter's sign of Sagittarius is trine to the Sun's sign of Leo and Jupiter's other sign of Pisces is trine to the Moon's sign of Cancer. The trine was seen as having something of the nature of Jupiter. By the same reasoning squares have something of the nature of Mars. Planets that are in signs that are related to each other by trine were seen as being in a harmonious relationship, even if one is at 0 degrees and the other is at 29 degrees.
In the seventeenth century Kepler tried to replace the sign based nature of aspects, solely with degree based aspects. So in his terms the Venus/Mars aspect would definitely be a square with all that entails. the signs are immaterial.
Kepler's basic idea stuck but not fully. Now all aspects are seen as degree based, by modern Astrologers, but they still hark back to the sign based rationale for the effect.
So how should you approach it? One approach is to look at the planets involved (which I think is what Kepler intended), thus we have a Mars/Venus aspect and traditionally Mars and Venus are seen as friends. So the aspect is not as full of tension and obstinacy as Mercury and Saturn, who are seen as enemies.
A second thing to bear in mind is that the Hellenistic Astrologers didn't assume that Venus at 0 degrees Sagittarius and Mars at 29 degrees Pisces were in the same sort of relationship as Venus at 15 degrees Sagittarius and Mars at 16 degrees Pisces. distance did matter. planets that are far away from each other in terms of sign placement at best have a nodding acquaintance and may simply be vaguely aware of the other. So by sign, there's just a hint of dislike between your suggested Mars and Sagittarius placements but the narrow separation by degree overcomes that.
But perhaps most important. Consider whether the aspect is applying or separating. In the Venus/Mars example it's most likely that they are separating (but by no means certain) They perfected the trine with Venus in Scorpio. Trines can only perfect if the signs of the planets are of the same element. If the planets' positions were reversed and Venus was applying from 29 degrees Pisces to a trine with Mars at 0 Sagittarius, Venus needs to change signs to Aries to complete the trine.
For reasons which I don't really understand many modern Astrologers ignore whether planets are applying or separating for natal work. They then make a great deal of importance out of Secondary Progressions, which by their very nature will only be effective if the aspects are applying.
When you move to synastry, as with your first example, I'm not sure that the same situation holds. Personally, I'm wary of drawing aspect conclusions from two separate charts. I don't mean by that it shouldn't be done but care is needed. Always start from the natal charts and draw up your analysis of character, temperament, personality or whatever you wish to call it. Then think how two such people might interact. That's how it used to be done. Extending to the interchart aspects will tease out some more about the relationship but going of the interchart aspects alone will likely result in getting it wrong.
It makes sens