Reference

Aspects

An aspect is the angle between two points in a chart. Two planets a third of the way around the wheel from each other are in a trine; directly across, an opposition. This site uses the five Ptolemaic aspects, and calculates them from real positions rather than by counting signs — which is why an aspect here can cross a sign boundary.

The five angles

The orb is how far from exact an aspect may sit and still count. There is no authoritative table; these are widely used moderate values, and they are wider for the aspects traditionally held to be strongest. The Sun and Moon are given two extra degrees, which is conventional.

What each one means

Not yet published. Every interpretive claim on this site has to trace to a cited source before it goes up, and the aspect descriptions are still being sourced. The geometry above is exact and needs no such warrant; what a square is traditionally held to signify does, and it will appear here when it has one.

Not every pair can form every aspect

This is astronomy rather than astrology. Mercury and Venus orbit inside the Earth’s orbit, so from here they never appear far from the Sun — which means some aspects between them simply cannot occur, in any chart, ever.

Measured rather than quoted: every body sampled monthly from 1900 to 2100 against the orbs above. Neptune and Pluto are the exception that proves the rule — they can reach a conjunction, but last did so in 1891, so no living chart contains one.

Aspects in your own chart

The birth chart page calculates every aspect between the planets in your chart, with its exact orb, from your date, time and place of birth. Nothing is transmitted; it is worked out on your own device.

Pages on individual pairings — what the Sun conjunct the Moon is held to mean, and its several hundred siblings — are being written and sourced. They are not here yet.