- State which stellium definition you use.
- Separate personal planets from slower generational planets.
- Follow the stellium ruler and its aspects.
Define the concentration
A stellium is a close concentration of several planets in one sign or house, but astrologers do not use one universal numerical definition. State which planets are included, their degrees, and whether the concentration is by sign, house, or close conjunction.
Three outer planets sharing a sign across many degrees carry a different personal emphasis from the Sun, Moon, Mercury, and Venus gathered closely together.
Give every planet its own job
Do not compress the stellium into one oversized sign description. Identify what each planet contributes, which conjunctions are exact, and whether one planet sits at the center of several contacts.
Personal planets make the concentration immediately psychological; social and outer planets add wider developmental or generational themes.
Read sign, house, and ruler
The sign describes the shared operating style, while the house shows where the concentration repeatedly becomes concrete. If the planets cross a house cusp, distinguish the two contexts.
Locate the ruler of the stellium sign. Its sign, house, and aspects reveal how the concentrated energy obtains direction and where it reports in the chart.
Look for an outlet
Planets aspecting the stellium can provide challenge, release, perspective, or practical expression. An opposition may externalize the missing pole, while a square demands development outside the concentration's familiar method.
The aim is not to weaken the stellium but to keep it connected to the rest of the chart.