Astrocartography Basics: How to Read Location Lines Without Overclaiming the Map

With a made-up Venus MC line at 30 degrees east, a city at 36 degrees east lies 6 degrees away, about 414 miles at the equator, and the line suggests warmth in public life, not good rent or jobs.

Astrocartography draws a map of the world with lines on it. Each line marks places where a planet was on one of the four angles of the sky at the moment you were born. The technique was developed by the American astrologer Jim Lewis in the 1970s, and he trademarked its name, written with an asterisk between Astro, Carto and Graphy.

The idea is that a planet’s meaning changes with the place where you stand. A planet that sat on the horizon for the people in one city sat low in the sky for the people in another, so the same chart is said to speak differently in different places.

Each planet has four lines, one for each angle: the Ascendant (AC), where the planet was rising on the eastern horizon; the Descendant (DC), where it was setting; the Midheaven (MC), where it was at its highest point; and the Imum Coeli (IC), where it was at its lowest point, opposite the MC.

The MC and IC lines run straight from north to south, because they depend only on longitude. The AC and DC lines curve, because they also depend on latitude. Each degree of longitude equals 4 minutes of Earth’s rotation, so places one degree apart in longitude see a planet cross the meridian about 4 minutes apart.

A standard map uses ten bodies: the Sun, the Moon and the eight planets from Mercury to Pluto. With four lines each, that makes 40 lines on one map. The map looks crowded, and many places are within a short distance of at least one line.

A crossing is a place where two lines meet, such as a Venus line and a Jupiter line. Astrologers read the two planets together there, since the place carries both themes. A crossing is a point of overlap and not a bonus, and the two themes may blend or pull against each other.

A relocation chart takes your birth moment and recasts the chart for a chosen place, which changes the angles and the houses while the planets keep their zodiac positions. It shows one place in full detail. An astrocartography map shows only where planets are angular, but it shows every place on Earth at once.

The two use the same birth moment and are two views of the same geometry, so they agree. The map helps you scan, and the relocation chart helps you read a single place in more depth.

Use the same short steps for every line you meet.

1. Name the planet and the angle, such as Venus on the MC.
2. Say what each means in everyday words: Venus is affection and values, MC is career and public life.
3. Combine them into a topic: a place where attention goes to your reputation for warmth, taste or cooperation.
4. Note the distance. The closer to the line, the more the reading applies, and there is no standard cutoff; some astrologers use a few degrees of longitude.
5. Write it as a question to test, not as a promise.

Suppose a made-up person has a Venus MC line running along 30 degrees east longitude. The IC line is exactly opposite, 180 degrees away, at 150 degrees west. A city at 36 degrees east is 6 degrees from the MC line. At 4 minutes of rotation per degree, that is 24 minutes of sky, and on the ground about 6 degrees times 69 miles per degree at the equator, or about 414 miles, less as you move toward the poles.

Venus MC would be read as a theme of warmth and taste in your public life there. Venus IC is a different topic: affection at home and in family. The map tells you which topic, and nothing about whether the job market, the rent or the people are good.

A map of lines describes symbolic geometry. It does not tell you where to live, and it cannot know about your job, your family, your safety or your money. Those are the factors that decide whether a move works.

If you are curious about a place, use the line as a prompt for a question, such as what you would want your life there to feel like, and then do the practical research. Visit if you can, talk to people who live there and check costs, visa rules and local safety directly. A line that fits a city does not make the move wise, and a line that does not fit does not make it a mistake.

The vertical MC and IC lines depend on the time of birth, so they slide east or west when the time is wrong. Earth turns 1 degree in 4 minutes, so each 4 minutes of error moves the lines about 1 degree of longitude. A degree is about 69 miles at the equator and shrinks toward the poles.

A birth time rounded to the nearest hour can therefore place a line in a different country. The AC and DC lines move too, and their curves change shape as well as position. If the time is uncertain, treat every line as a rough band and not a thin stripe.

Does moving change my birth chart? No. The chart and its lines belong to the birth moment. Only a relocation chart is recast for the place where you stand.

Do the lines apply to a visit or only to living somewhere? Astrologers differ. Some read a short trip lightly and a long stay as a fuller theme, and others read both the same way. There is no good evidence that a line predicts how a trip or a move goes.

Why do maps from two programs differ? The usual causes are the birth time entered and the set of bodies drawn, since some programs add the lunar nodes or Chiron to the ten standard bodies.

A line cannot tell you where to live, and it knows nothing about your job, family, safety, money or visa rules.