How to read an astrocartography chart

Before you start: your birth details

A map is only as good as the birth data behind it. You need your date, place and time of birth, and the time matters most. Use a birth certificate or hospital record if you can; a time remembered by family is often rounded to the nearest half hour. If you are not sure, enter your best guess and tell the map how sure you are. It then shades the zone where each line could fall.

Step 1: tell the four line styles apart

Every planet has four lines, and each is drawn in its own style so you can tell them apart at a glance.

• MC lines are solid and straight. They run due north to south, where the planet was at the top of the sky.
• IC lines are dashed and straight. Also north to south, exactly half a world (180 degrees of longitude) from the MC line, where the planet was underfoot.
• AC lines are solid curves. They mark where the planet was rising in the east.
• DC lines are dashed curves. They mark where the planet was setting in the west.

Straight lines are straight because a planet crosses a whole meridian, pole to pole, at the same instant. The rising and setting lines curve because the horizon is tilted differently at each latitude. Near the equator a planet's AC line sits 90 degrees of longitude west of its MC line, and its DC line 90 degrees east. Toward the far north or south the two curves bend in and meet, at latitude 90 minus the planet's declination; beyond it the planet did not rise or set that day, so there are no AC or DC lines for it there.

Step 2: astrocartography symbols and key

The key to an astrocartography chart has two halves: a symbol and color for each body, and a label and line style for each angle. Each body has a traditional glyph and, on our map, its own color, used for all four of its lines. Astrocartography symbols are the same glyphs used in any birth chart.

Symbol	Body	Line color	Themes
☉	Sun	Gold	Visibility, confidence, purpose
☽	Moon	Pale silver	Home, feelings, belonging
☿	Mercury	Mint green	Words, study, contacts
♀	Venus	Pink	Love, beauty, ease
♂	Mars	Coral red	Drive, courage, friction
♃	Jupiter	Lavender	Opportunity, growth, generosity
♄	Saturn	Sand	Structure, effort, commitment
♅	Uranus	Sky blue	Change, freedom, surprise
♆	Neptune	Periwinkle blue	Imagination, ideals, haze
♇	Pluto	Magenta	Intensity, depth, power
☊	North Node	Lime green	Direction, meaningful meetings
⚷	Chiron	Orange	Sensitivity, healing, mentoring

The four angle labels are the other half of the code:

Label	Name	On the map	Area of life
AC (or ASC)	Ascendant, rising	Solid curve	You: body, image, energy
DC (or DSC)	Descendant, setting	Dashed curve	Others: partners, allies, rivals
MC	Midheaven	Solid straight line	Career, reputation, direction
IC	Imum Coeli	Dashed straight line	Home, family, roots

Put the two halves together and you have the name of the line: a pink dashed curve labeled ♀ DC is the Venus DC line; a sand-colored solid straight line labeled ♄ MC is the Saturn MC line.

Step 3: find the places you care about

Rather than scanning the whole world, start with places that matter to you: where you live, where you grew up, a city you are thinking about. Search a city or click anywhere on the map, and it lists the nearest lines with their distance in kilometers and miles and their direction from that place. That turns dozens of lines into the three or four that are actually close to you.

Step 4: read planet and angle together

Every line is a sentence with two words. The planet is the verb, the angle is the setting. Jupiter is read as growth and opportunity; on the MC that becomes opportunity in public life, on the IC a generous home. Saturn is read as structure and effort; on the DC that becomes committed, serious relationships, on the AC a reserved, focused manner.

Read each line for both sides. Tradition calls Venus and Jupiter lines the gentle ones and Saturn, Mars and Pluto the demanding ones, but a gentle line can be too comfortable to get anything done and a demanding one can be where you build what lasts. Ask "good for what?" rather than "good or bad?". Some traditional astrologers also weigh whether you were born by day or by night, reading Saturn as milder in a day chart and Mars as milder in a night chart. The line pages give strengths and challenges for all 48.

Step 5: decide how close counts

This is the question beginners ask most, and there is no single answer. Astrologers from different schools use different distances. Many give the most weight to places within a few hundred kilometers of a line and treat the effect as fading with distance; some still count a line much farther out. That is why our map shows the exact distance to each line instead of a yes or no. Pick a rule you find sensible and apply it the same way to every city.

Step 6: look at crossings and parans

Where two lines cross on the map, both planets were on angles at the same moment for that spot. Astrologers read a crossing as a blend of both planets. Many also extend it into a paran: the whole band of latitude where those two planets were angular together, running all the way around the world. That is why a crossing in the middle of an ocean can still matter for a city thousands of kilometers east or west of it, as long as the city sits near the same latitude. Turn on parans in the Lines tab to see them drawn.

Step 7: check how much your birth time moves things

The Earth turns one degree every four minutes. So if your birth time is four minutes off, every line on your map shifts one degree of longitude, about 111 km (69 miles) at the equator and less toward the poles. A time off by a quarter of an hour moves lines almost four degrees. If a city sits right on the edge of a line, a small time error can move it in or out. The uncertainty band on the map shows this zone directly.

Without a birth time

If you do not know your birth time at all, choose "I don't know my birth time" in the Birth tab. Planet lines depend on how far the Earth had turned at your birth, so without a time the map draws none rather than guess.

Instead it shows your paran latitudes, calculated for noon of your birth day. A paran is a latitude where two planets were on angles together, and it depends on where the planets stood among the stars, which changes only slowly over a day. So for every body except the Moon, the paran latitudes barely move whatever time you were actually born. The Moon is left out, because it moves about 13 degrees a day and its parans shift with the hour.

Read these the same way as any paran: a band about 1 degree north or south of each latitude, running all the way around the world. If you later find your birth time, enter it and the full map of lines appears.

In the sky or on the ecliptic

Lines can be calculated two ways. In the sky (in mundo, our default) uses each planet's true position, including its small distance north or south of the zodiac band. On the ecliptic uses only its zodiac degree, the way a chart wheel does. For the Sun they are identical and for most planets they are close; for Pluto they can differ by up to about 7 degrees of longitude, and for Venus, Mars and the Moon by 2 to 3.5 degrees, because these bodies can stray furthest from the ecliptic as seen from Earth.

This explains a common puzzle. You stand on your Venus AC line, open the relocation chart, and Venus is a few degrees away from the Ascendant. Nothing is broken: the line uses the sky method and the chart uses zodiac degrees. Switch the map to "On the ecliptic" and they agree exactly. Neither method is wrong; astrologers simply prefer different ones.

Why maps differ between sites

1. Birth time, as in step 7: a few minutes moves everything.
2. Line method: in the sky or on the ecliptic.
3. Time zone history: old daylight saving rules can move the true moment of birth by an hour.
4. Node: the true node and the mean node sit in slightly different places.
5. Calculation: rounding and simplified formulas. Ours are published on the method page.

The house system you choose (Placidus, Whole Sign or Equal) does not move any line. Lines are angles, not houses. It only changes the houses in the relocation chart.

Flat map distortion near the poles

A flat map stretches the far north and south. One degree of longitude is about 111 km at the equator but shrinks toward the poles, while the map draws every degree the same width. So in Scandinavia or Canada two lines can look far apart and still be close in kilometers. Read distances from the list, not by eye, or switch to the 3D globe, which shows the true shape.

Common mistakes

• Reading every line on the world instead of the few near places you care about.
• Treating Saturn, Mars or Pluto lines as places to avoid at all costs.
• Using a rounded birth time without checking the uncertainty band.
• Judging distances by eye on the flat map at high latitudes.
• Forgetting that a place with no lines nearby is not empty: your natal chart still applies there, with its houses relocated.
• Letting a line outweigh work, visas, cost of living, family and how a place actually feels when you are there.

What to do next

Draw your free map, click the cities on your shortlist and read the lines near each. Compare up to three side by side, open the relocation chart for the one you like most, and read the full page for each line that is close. If you want a place for a particular goal, start from best places by theme. New to the whole idea? Read what astrocartography is first.