How We Compute
the Sky
The positions, dates and map lines we publish are calculated, not copied, and tested against an independent reference. This page explains how, and what the numbers can and cannot tell you.
Planet Positions
Your chart is computed in your browser from your birth date, time and place. Planet positions come from published astronomical algorithms, principally Jean Meeus’ Astronomical Algorithms, with precession to the equinox of date. We use the tropical zodiac for Western astrology and the Lahiri ayanamsa for the sidereal zodiac used in Vedic readings.
Before every release the chart engine is tested against reference positions generated from JPL data. Across the twelve reference charts in that test, the largest errors are 0.014° for the Sun, 0.019° for the Moon, 0.023° for Venus, 0.097° for Jupiter and 0.162° for Saturn. None of those is large enough to move a planet into a different sign unless it sits within a fraction of a degree of the boundary.
Historical time zones and daylight saving come from the IANA time zone database built into your browser, so a birth in 1970s Sydney or wartime London is converted to universal time with the rules that applied on that day.
Astrocartography Lines
Each planet draws four lines across the map: where it was rising, setting, overhead and underfoot at the moment you were born. We compute them from the same positions, converted to right ascension and declination and set against sidereal time.
We audited the engine against Swiss Ephemeris, an independent code base that shares nothing with ours. The largest line error was about 1.2 miles at the equator, typically around 0.4 miles, and smaller at higher latitudes. The small remainder exists because we plot geometric positions while some other sites plot apparent ones; it is far smaller than the uncertainty in almost anyone’s recorded birth time.
That uncertainty matters more than the math. The Earth turns one degree every four minutes, so a four-minute error in your birth time shifts every line by about one degree of longitude, roughly 110 km at the equator. If your time is rounded to the hour, read the lines as zones, not streets.
Dates We Publish
Eclipses, retrogrades, stations and ingresses appear across our calendars, forecasts and email alerts. They all come from one computed calendar, and an automated check runs before every deploy: it re-derives each station and ingress from the ephemeris, then checks the dated sky claims on our pages against that calendar. A page that disagrees does not ship.
Dates are given in universal time. An event late in a UTC day can fall on the previous evening in the Americas, and we say so where it matters.
How Readings Are Written
Paid readings are written by AI from your computed chart. The model receives the positions, houses, periods and dates we calculated, and it is instructed never to state a placement, aspect or date that is not in that data.
Each part of a reading is then checked automatically against the computed facts: dates, periods and aspect claims. If a part contradicts the data, it is sent back once with the specific errors named and rewritten before it reaches you. The interpretation is written language; the facts underneath it are not left to chance.
What We Don’t Claim
Astrology is not a science, and we do not present it as one. There is no established mechanism by which planets shape a person or a place, and our readings describe themes and conditions, not fixed outcomes. We will never tell you that a person is coming, that a date guarantees anything, or that a city will fix your life.
What we do claim is narrower and checkable: the sky data is right. If the Moon was at 10° Pisces when you were born, it says 10° Pisces. If Venus turns retrograde on October 3, the date is October 3. Readings are for reflection and entertainment, not medical, legal or financial advice.
Corrections
When we find an error, we fix it at the source and every page that repeats it. In September 2026 we checked every dated sky claim on the site against the ephemeris, corrected our retrograde and eclipse pages, and retired a historical archive whose claims did not hold up to that check.
We apply the same check to what others publish. In September 2026 we scored the top 20 Google results for Mercury retrograde 2026 dates against the ephemeris and published the results.
If you spot something wrong, tell us. Send the page and what you believe the correct value is; we check it against the ephemeris and correct it if you are right.
See it on your chart
Your planetary lines and the cities they cross, computed in seconds.
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