Stellium, Midheaven, Vertex and Part of Fortune Calculator

The result shows:

• Your Midheaven (MC) and Imum Coeli (IC), by sign and degree
• Your Descendant sign
• Your chart ruler, with the sign and house it sits in
• Your Part of Fortune
• Your Vertex
• Any stelliums: three or more planets, Sun through Pluto, in one sign or one house
• Any grand trines

Birth time and place are required. The angles, the Part of Fortune and the Vertex all depend on them. The calculator is free, and the points are for reflection and entertainment.

The midheaven is the point of the zodiac highest in the sky at your birth, directly overhead along the line running north to south. It's read as your public role, reputation and the direction your work takes. Your midheaven sign is the sign on that point, and the degree tells you how far into it the point sits.

The Imum Coeli is the opposite point, the lowest in the sky. It's linked with home, family and your roots. The Descendant is opposite your rising sign and is read as the style of partner you're drawn to. Find your rising sign with its own calculator.

Your chart ruler is the planet that rules your rising sign. Astrologers read its sign and house as a clue to where your chart's main thread runs. This calculator uses the traditional rulers:

Aries and Scorpio: Mars. Taurus and Libra: Venus. Gemini and Virgo: Mercury. Cancer: Moon. Leo: Sun. Sagittarius and Pisces: Jupiter. Capricorn and Aquarius: Saturn.

If your rising sign is Virgo, for example, your chart ruler is Mercury. If Mercury sits in your 10th house, career is where that thread shows up.

The Part of Fortune is a calculated point, not a planet. It's an old Hellenistic technique, traditionally tied to well-being, luck and where things come easily.

The formula depends on whether you were born in daylight:

• Day birth (the Sun is above the horizon): Ascendant plus Moon, minus Sun.
• Night birth (the Sun is below the horizon): Ascendant plus Sun, minus Moon.

The calculator checks the Sun's position for you and uses the right formula. Because it starts from the Ascendant, it needs an accurate birth time.

The vertex is a sensitive point in the west of the chart. It's the place where the ecliptic, the Sun's path through the zodiac, crosses the prime vertical. The prime vertical is an imaginary circle that runs from due east, up through the point straight overhead, and down to due west.

Some astrologers link the vertex to fated encounters and turning points, often with other people. It's a minor point, and opinions on it vary. The calculator finds it from this geometric definition, using your birth time and place.

A stellium is a cluster of three or more planets in the same sign or the same house. In this calculator, planets means the Sun through Pluto. A sign stellium and a house stellium are counted separately, and both show up if you have them.

A stellium in a sign is read as a theme that gets a lot of weight in your chart. The planets share the same flavor, so that sign's traits can feel strong in you. A house stellium puts the focus on one area of life, such as work, relationships or home.

Four stelliums come up most often in searches:

• Capricorn stellium: ambition, discipline and a steady, long-view approach to work.
• Scorpio stellium: intensity, privacy and a pull toward depth and change.
• Pisces stellium: imagination, empathy and a porous, intuitive way of taking things in.
• Sagittarius stellium: restlessness, optimism and a need for freedom and meaning.

Which planets are involved matters as much as the sign. A stellium of the Sun, Mercury and Venus reads differently from one of Mars, Saturn and Pluto.

A grand trine is three planets about 120° apart, forming a triangle in the chart. The three are usually in the same element: fire, earth, air or water. Astrologers read it as a flow of ease and natural talent between those planets. The common caution is that easy energy can make a person coast, so the talent may need a push to turn into something.

The midheaven moves about one degree every four minutes, and the Ascendant changes sign roughly every two hours. A few minutes can change your MC degree, and a few hours can change your MC sign, your chart ruler and your house stelliums. Day or night also decides which Part of Fortune formula applies.

Check your birth certificate for the time. If you don't have it, the sign-level results for planets still hold, but the angles, Part of Fortune, Vertex and house stelliums will not be reliable.

For the full wheel with every planet and house, see your free birth chart. It also has the paid written reading.