BIRTHPRINT

A beautiful portrait. Clear methods.

One instant around the Sun

Birthplace supplies the time zone for converting local birth time to UTC. It does not change heliocentric positions at the same instant. Unknown birth time uses 12:00 local noon, clearly marked approximate. The solar-system background is artistic, separate from the calculated bodies.

What the validation can tell you

Reference checks against JPL Horizons cover selected bodies and supported birth dates, not every possible moment. They compare calculated coordinates, not the artistic spacing on screen. No single accuracy figure applies to the whole experience. Distant dates, incomplete historical time-zone records and an unknown birth time each introduce different limitations. Astrological interpretations are symbolic entertainment, separate from astronomical coordinates.

Astronomy and time

Astronomy Engine 2.1.19 calculates geometric heliocentric positions in the J2000 mean ecliptic frame and axial orientation using IAU rotation elements. The page captures its opening instant. The birth form supports 1900 through today. A valid Reveal submission changes the scene and reading together; camera controls do not change time. Local times use 00–23 hours. Browser IANA time-zone data applies historical clock changes; records before 1970 can be incomplete. Gaps are rejected and repeated times require a choice.

Display scale and motion

Calculated heliocentric directions are preserved. Enlarged bodies occupy fixed, separated radial bands, including the Moon’s orbit and Saturn’s full rings. A small, smooth distance term preserves eccentric motion; there is no date-dependent collision avoidance. Orbit guides remain visible and sample one orbital period. Transition frames recalculate the displayed instant. Nebulas, asteroid distribution, glows and the Sun’s fluid texture animation are artistic effects; individual asteroids and solar weather are not reconstructed.

Calendars and interpretations

The tropical Sun sign is calculated from apparent solar longitude; Moon sign from lunar longitude. Unknown time checks both ends of the local civil day for sign changes. Chinese year follows ICU’s Chinese calendar and lunar new year. Hebrew and tabular Islamic-civil conversions use the entered civil day at noon, without sunset adjustment. Numerology sums the date digits to 1–9 without retaining master numbers.

Place search and historical time

Open-Meteo searches the worldwide GeoNames catalogue, including smaller towns and villages, with normalized names, regional qualifiers, coordinates and IANA zones. Only the search text and language go through our server to Open-Meteo; birth dates, times and names are not sent. If a place is missing, enter its exact coordinates and verified IANA zone manually. Present-day geographic zones cannot resolve every historical boundary change: check old records and the displayed UTC offset. No nearby-town substitution is required.

Planet placements

Floating readings use apparent geocentric longitude in the true ecliptic and equinox of date, including light-time and aberration, calculated with Astronomy Engine. The Western tropical zodiac divides longitude into twelve 30° signs. Motion is the wrapped longitude difference over ±12 hours; less than 0.005° per day is labelled near stationary. Major aspects are conjunction, sextile, square, trine and opposition within a 3° orb, with the two closest shown. Earth is the viewpoint and has no geocentric placement. Unknown birth time uses local noon. Houses are omitted. Interpretations are symbolic entertainment, not personality assessments or scientific predictions. Longitude checks against JPL Horizons quantity 31 covered 72 samples; the largest difference was 0.0043°. Everyday distances are geometric center-to-center distances in kilometres: the Earth’s heliocentric distance and the geocentric Moon vector length. The retrograde count includes Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune; near-stationary bodies are excluded. Reflection selects a personal-planet placement, the closest eligible major aspect (preferring a personal body), and the Moon phase. Astrological themes are attributed symbolism, not causation. Unknown-time facts describe the assumed noon instant.

Sources and licenses

Content reviewed: 22 September 2026