What is a conjunction?
Two planets sitting at the same degree of the chart, or within a few degrees of it, form a conjunction. Zero distance, the closest contact two points can make. The energies do not take turns. They blend into one voice, and which planets meet changes everything about the tone. Moon Shine AI marks the conjunctions that are live in your chart, along with how tight the orb between them is.
Classical astrology barely called it an aspect
For a long stretch of the tradition the conjunction was not filed with the aspects at all. Ptolemy put it in a category of its own. His reasoning was that an aspect means one planet looking at another across a distance, and two planets sharing a degree are not looking at anything. Modern sources moved it into the major aspects, precisely because its effect outweighs the rest.
Distance is the whole difference. A trine supports from 120° away, a square grinds from 90° away. In a conjunction there is no away. Two bodies occupy one point and breathe at the same degree, which is why you get a single mixed voice instead of two separate ones.
That also makes it the hardest aspect to interpret. Reading each planet separately and adding the results does not work. You have to look at how the two behave as a compound from the start. In a chart carrying several squares and trines, it is very often the conjunction that a reader notices first, before anything else declares itself.
Which planets meet, and how far the tone shifts
Sun conjunct Moon is a New Moon by another name, with identity and feeling pointing the same way. People born under it tend to know what they want without much inner argument. Venus conjunct Mars mixes affection and desire directly, which usually shows up as a frank and fairly intense style of relating. Mercury with Jupiter turns the speech enthusiastic and occasionally oversized, losing a detail here and there while gaining the wider view.
Saturn brings the demanding version. When it joins a personal planet, whether that is the Moon, Venus or Mercury, the expression of that planet picks up weight, caution and sometimes restriction. Feelings with Moon and Saturn. The way someone loves with Venus and Saturn. The way they think with Mercury and Saturn. All of it turns more serious and more disciplined, heavy at first and generally read later as a placement that delivers maturity.
Pluto pushes intensity to its ceiling. A personal planet joined to Pluto takes on an obsessive, transformative colour in its own area of life. The early 1990s carried a generational Uranus and Neptune conjunction shared by everyone born in that stretch, which marks an era rather than a person. A conjunction falling on a personal planet is a different matter. There the story stops being collective and becomes entirely individual.
What a tight orb changes
Orb measures how far the actual degree gap sits from the exact aspect. At 0° the conjunction is perfect, at 1 or 2 degrees it is still very strong, and by 6 or 7 degrees the bond starts to loosen. Between Sun and Moon astrologers allow as much as 8 to 10 degrees. With finer bodies such as Mercury or Venus, going past 3 or 4 degrees already begins to weaken the contact.
A tight orb of 0 to 3 degrees puts the conjunction in the middle of daily life. The theme shows up on most days of the week. A wide orb of 6 degrees or more leaves a background effect that surfaces only in certain phases.
Venus conjunct Uranus makes the point concretely. With a 3 degree orb it tends to bring sudden ruptures and unexpected attractions in relationships, and the person usually recognises it immediately with specific stories to tell. At 7 degrees the same pairing goes quiet and may amount to little more than getting bored of routine. Same aspect, different volume.
House placement finishes the picture. A conjunction in the first house works on identity as it faces outward. In the seventh it plays out through partnership. In the tenth it takes to career and public role. The planets can be identical while the stage is completely different.
How to read one without over-reading it
Start with which planets are involved, then the orb, then the house. Reversing that order leaves the reading floating, because without the house you have no ground to put it on. It also helps to think about the natural character of each body. Mars with Saturn slows the drive down and teaches patience, while stacking up some contained frustration along the way. Mars with Jupiter does the opposite and produces enthusiastic momentum with a real appetite for risk.
Conjunctions involving a retrograde planet deserve their own note. If one of the two is retrograde at the moment of contact, a more inward version of the theme appears and it matures more slowly. Someone with Venus conjunct a retrograde Mercury may take a long time to put affection into words, with none of the depth missing.
Worth remembering that a single conjunction does not summarise a chart. It gets read alongside the other aspects, the houses and the rulers, and that wider view is what turns one striking contact into an actual interpretation.
Curious which conjunctions are live in your chart and how tight the orbs are? Ask Selene in Moon Shine AI and we can go through them one by one.
Is a conjunction always positive?
No, it depends on the planets. Venus with Jupiter often produces a pleasant sense of abundance, while Saturn or Pluto can bring weight and intensity. Rather than good or bad, look at which energies are being fused.
How many degrees still count as a conjunction?
Up to 8 degrees is generally accepted, though it varies by planet. Sun and Moon take a wider orb, and with fast bodies like Mercury or Venus anything past 3 or 4 degrees already starts to weaken the contact.
What if three planets come together at once?
That is called a stellium and it is a different matter from a simple conjunction. When three or more planets gather in one sign or house, that zone becomes the centre of gravity of the whole chart.