ASTROCARTOGRAPHY
Why lines bend, split or stop
The map drawing is a projection of geographic curves. Its appearance should not be confused with either a distance measurement or an interpretation.
The idea in context
The shape of a line follows the chosen angular condition and the way a globe is displayed on a flat map.
MAKE IT CONCRETE
An example to picture
A line that exits the right edge and reappears on the left can be continuous across the antimeridian. The split is a drawing choice, not a measured distance or a change in the line’s meaning.
How to read it
Use the body-and-angle label and follow the line’s geographic continuity. Do not treat screen spacing or interruptions as a city-distance measurement or a symbolic warning.
A common misunderstanding
A broken drawing segment is not a break in a person’s possibilities, and a line’s screen length does not measure importance.
BRING IT BACK TO YOUR LIFE
A question to sit with
Which part of what you see is a geographic fact, and which is a drawing choice?
Go deeper: the full reference
Meridians and horizon curves
MC and IC families follow meridian longitudes. AC and DC families generally curve because the horizon condition changes with latitude and a body’s declination. A curve does not show the planet’s orbit, and a straight line does not indicate a stronger effect.
At the map edge
The antimeridian is where many world maps wrap between their left and right edges. A continuous geographic line may therefore appear as separate drawing segments. The renderer should not join those segments with a false stroke across the map. A separate native-model distance calculation must also account for that boundary; the current web map does not calculate proximity.
At high latitudes
For some latitudes and declinations, a body does not meet the geometric horizon during the modeled daily rotation. A rising or setting branch can stop rather than continuing into every latitude. The source map also excludes the exact poles from its sampled drawing. Missing strokes are not evidence of a missing planetary theme.
Screen appearance and numeric distance
Projection and drawing thickness can change how close lines look. Do not estimate city-to-line distance from the web map’s screen spacing. The native proximity model uses geographic geometry, but that result is not supplied here. The angular-line model omits local mountains, observer height, refraction and parallax; it is not a forecast of an observed sky event.
Try reading a chart
Find the same symbol in your chart or a public profile. Compare the displayed positions with the lesson, and keep the recorded birth-time confidence in mind.
Connect the ideas
What an astrocartography map shows
An astrocartography map places the birth sky on a world map by marking where each supported body meets one of four angular conditions at the recorded birth instant.
2 min readWhy birth time matters on the map
Angular lines depend on Earth’s orientation at the recorded birth instant, so an uncertain time can shift the geographic result.
2 min readDistance bands in the native calculation model
The native calculation model measures a place’s distance from an angular line. This lesson explains that method; the web map displays lines without a city-distance calculator.
3 min readAC lines: presence and beginnings
An AC line marks the locations where a body meets the eastern side of the modeled horizon at the recorded birth instant.
2 min read