Learn · Five chart patterns
The stellium
A stellium is three or more planets gathered in one sign or one house: it concentrates a chart in one place and gives that sign or area of life an outsized part in a life.
Some part of your life takes up more room than everything else, and you stopped apologising for it years ago. The subject comes up whatever the conversation, and the people close to you know which one it is. A stellium is the chart’s version: three or more bodies in the same sign, or the same house, so that one place carries more weight than any single placement could.
The tradition had no name for it. Modern astrology took the word from the Latin for a group of stars, and reads the pattern as a theme strong enough to rival the Sun sign.
In your chart
The chart sorts the Sun, the Moon and the eight planets by sign and by house, and names a stellium wherever three or more land together. The inner planets travel with the Sun, so a stellium often includes Mercury or Venus beside it, and one built around the Sun gives an identity that is strongly marked. A stellium of slow planets, such as Saturn, Uranus and Neptune together, is shared with a whole generation and becomes personal only through its house. The house is where the chart lives most of its life, and the sign gives the manner.
From a real analysis
In her chart: Stellium in Capricorn: Saturn, Uranus, Neptune
The second shape is three slow planets bunched together in Capricorn, a cluster that gives you a serious, structured streak underneath the lightness. You want your plans to last, and you build them with care.
Themes
A stellium is intensity and single-mindedness. Whatever the sign and house, you come back to that area again and again, become very good at it, and find it hard to see the world through any other lens. A Gemini stellium lives in words and connections; one in the tenth house is organised around a vocation. The way in is always the same: follow the subject, and ask what the bodies in it want from each other.
The edge is imbalance. So much of the chart is spent in one place that the opposite sign and house go unattended, and what they hold arrives, sooner or later, as a surprise. The analysis reads a stellium beside what sits across from it.
What to look at first
Which bodies form it matters more than how many. A stellium of personal planets is yours alone; one of outer planets is shared with everyone your age. Aspects from other bodies to the stellium describe what steadies it or stretches it.
How the analysis treats it
The chart-patterns chapter gives each stellium its own paragraph, naming the bodies, the sign or house, the element and modality, and how the concentration shows in a life. The balance figures show it too.
Every pattern found in a chart is drawn on the chart page with only the bodies in it, and the analysis gives it a paragraph of its own.
Sources: every position and date here comes from NASA JPL’s DE440 ephemeris and is checked against NASA’s JPL Horizons. How it is checked.
A stellium in your chart?
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